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Sample records for beneficial rhizobacterium pseudomonas

  1. Draft Genome Sequence of the Beneficial Rhizobacterium Pseudomonas fluorescens DSM 8569, a Natural Isolate of Oilseed Rape (Brassica napus)

    PubMed Central

    Nesemann, Kai; Braus-Stromeyer, Susanna A.; Thuermer, Andrea; Daniel, Rolf

    2015-01-01

    Pseudomonas fluorescens DSM 8569 represents a natural isolate of the rhizosphere of oilseed rape (Brassica napus) in Germany and possesses antagonistic potential toward the fungal pathogen Verticillium. We report here the draft genome sequence of strain DSM 8569, which comprises 5,914 protein-coding sequences. PMID:25814596

  2. Draft Genome Sequence of the Beneficial Rhizobacterium Pseudomonas fluorescens DSM 8569, a Natural Isolate of Oilseed Rape (Brassica napus).

    PubMed

    Nesemann, Kai; Braus-Stromeyer, Susanna A; Thuermer, Andrea; Daniel, Rolf; Braus, Gerhard H

    2015-03-26

    Pseudomonas fluorescens DSM 8569 represents a natural isolate of the rhizosphere of oilseed rape (Brassica napus) in Germany and possesses antagonistic potential toward the fungal pathogen Verticillium. We report here the draft genome sequence of strain DSM 8569, which comprises 5,914 protein-coding sequences.

  3. Genome sequence of the plant growth-promoting rhizobacterium Pseudomonas putida S11.

    PubMed

    Ponraj, Paramasivan; Shankar, Manoharan; Ilakkiam, Devaraj; Rajendhran, Jeyaprakash; Gunasekaran, Paramasamy

    2012-11-01

    Here we report the genome sequence of a plant growth-promoting rhizobacterium, Pseudomonas putida S11. The length of the draft genome sequence is approximately 5,970,799 bp, with a G+C content of 62.4%. The genome contains 6,076 protein-coding sequences.

  4. Genome Sequence of the Banana Plant Growth-Promoting Rhizobacterium Pseudomonas fluorescens PS006.

    PubMed

    Gamez, Rocío M; Rodríguez, Fernando; Ramírez, Sandra; Gómez, Yolanda; Agarwala, Richa; Landsman, David; Mariño-Ramírez, Leonardo

    2016-05-05

    Pseudomonas fluorescens is a well-known plant growth-promoting rhizobacterium (PGPR). We report here the first whole-genome sequence of PGPR P. fluorescens evaluated in Colombian banana plants. The genome sequences contains genes involved in plant growth and defense, including bacteriocins, 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase, and genes that provide resistance to toxic compounds.

  5. Genome Sequence of the Banana Plant Growth-Promoting Rhizobacterium Pseudomonas fluorescens PS006.

    PubMed

    Gamez, Rocío M; Rodríguez, Fernando; Ramírez, Sandra; Gómez, Yolanda; Agarwala, Richa; Landsman, David; Mariño-Ramírez, Leonardo

    2016-01-01

    Pseudomonas fluorescens is a well-known plant growth-promoting rhizobacterium (PGPR). We report here the first whole-genome sequence of PGPR P. fluorescens evaluated in Colombian banana plants. The genome sequences contains genes involved in plant growth and defense, including bacteriocins, 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase, and genes that provide resistance to toxic compounds. PMID:27151797

  6. Complete Genome of the Plant Growth-Promoting Rhizobacterium Pseudomonas putida BIRD-1

    SciTech Connect

    Matilla, M.A.; van der Lelie, D.; Pizarro-Tobias, P.; Roca, A.; Fernandez, M.; Duque, E.; Molina, L.; Wu, X.; Gomez, M. J.; Segura, A.; Ramos, J.-L.

    2011-03-01

    We report the complete sequence of the 5.7-Mbp genome of Pseudomonas putida BIRD-1, a metabolically versatile plant growth-promoting rhizobacterium that is highly tolerant to desiccation and capable of solubilizing inorganic phosphate and iron and of synthesizing phytohormones that stimulate seed germination and plant growth.

  7. Comparative genomic analysis and phenazine production of Pseudomonas chlororaphis, a plant growth-promoting rhizobacterium

    PubMed Central

    Chen, Yawen; Shen, Xuemei; Peng, Huasong; Hu, Hongbo; Wang, Wei; Zhang, Xuehong

    2015-01-01

    Pseudomonas chlororaphis HT66, a plant growth-promoting rhizobacterium that produces phenazine-1-carboxamide with high yield, was compared with three genomic sequenced P. chlororaphis strains, GP72, 30–84 and O6. The genome sizes of four strains vary from 6.66 to 7.30 Mb. Comparisons of predicted coding sequences indicated 4833 conserved genes in 5869–6455 protein-encoding genes. Phylogenetic analysis showed that the four strains are closely related to each other. Its competitive colonization indicates that P. chlororaphis can adapt well to its environment. No virulence or virulence-related factor was found in P. chlororaphis. All of the four strains could synthesize antimicrobial metabolites including different phenazines and insecticidal protein FitD. Some genes related to the regulation of phenazine biosynthesis were detected among the four strains. It was shown that P. chlororaphis is a safe PGPR in agricultural application and could also be used to produce some phenazine antibiotics with high-yield. PMID:26484173

  8. Comparative genomic analysis and phenazine production of Pseudomonas chlororaphis, a plant growth-promoting rhizobacterium.

    PubMed

    Chen, Yawen; Shen, Xuemei; Peng, Huasong; Hu, Hongbo; Wang, Wei; Zhang, Xuehong

    2015-06-01

    Pseudomonas chlororaphis HT66, a plant growth-promoting rhizobacterium that produces phenazine-1-carboxamide with high yield, was compared with three genomic sequenced P. chlororaphis strains, GP72, 30-84 and O6. The genome sizes of four strains vary from 6.66 to 7.30 Mb. Comparisons of predicted coding sequences indicated 4833 conserved genes in 5869-6455 protein-encoding genes. Phylogenetic analysis showed that the four strains are closely related to each other. Its competitive colonization indicates that P. chlororaphis can adapt well to its environment. No virulence or virulence-related factor was found in P. chlororaphis. All of the four strains could synthesize antimicrobial metabolites including different phenazines and insecticidal protein FitD. Some genes related to the regulation of phenazine biosynthesis were detected among the four strains. It was shown that P. chlororaphis is a safe PGPR in agricultural application and could also be used to produce some phenazine antibiotics with high-yield. PMID:26484173

  9. Complete Genome Sequence of the Rhizobacterium Pseudomonas trivialis Strain IHBB745 with Multiple Plant Growth-Promoting Activities and Tolerance to Desiccation and Alkalinity

    PubMed Central

    Swarnkar, Mohit Kumar; Vyas, Pratibha; Rahi, Praveen; Thakur, Rishu; Thakur, Namika; Singh, Anil Kumar

    2015-01-01

    The complete genome sequence of 6.45 Mb is reported here for Pseudomonas trivialis strain IHBB745 (MTCC 5336), which is an efficient, stress-tolerant, and broad-spectrum plant growth-promoting rhizobacterium. The gene-coding clusters predicted the genes for phosphate solubilization, siderophore production, 1-aminocyclopropane-1-carboxylate (ACC) deaminase activity, indole-3-acetic acid (IAA) production, and stress response. PMID:26337878

  10. Complete Genome Sequence of the Rhizobacterium Pseudomonas trivialis Strain IHBB745 with Multiple Plant Growth-Promoting Activities and Tolerance to Desiccation and Alkalinity.

    PubMed

    Gulati, Arvind; Swarnkar, Mohit Kumar; Vyas, Pratibha; Rahi, Praveen; Thakur, Rishu; Thakur, Namika; Singh, Anil Kumar

    2015-01-01

    The complete genome sequence of 6.45 Mb is reported here for Pseudomonas trivialis strain IHBB745 (MTCC 5336), which is an efficient, stress-tolerant, and broad-spectrum plant growth-promoting rhizobacterium. The gene-coding clusters predicted the genes for phosphate solubilization, siderophore production, 1-aminocyclopropane-1-carboxylate (ACC) deaminase activity, indole-3-acetic acid (IAA) production, and stress response. PMID:26337878

  11. Quorum sensing systems differentially regulate the production of phenazine-1-carboxylic acid in the rhizobacterium Pseudomonas aeruginosa PA1201

    PubMed Central

    Sun, Shuang; Zhou, Lian; Jin, Kaiming; Jiang, Haixia; He, Ya-Wen

    2016-01-01

    Pseudomonas aeruginosa strain PA1201 is a newly identified rhizobacterium that produces high levels of the secondary metabolite phenazine-1-carboxylic acid (PCA), the newly registered biopesticide Shenqinmycin. PCA production in liquid batch cultures utilizing a specialized PCA-promoting medium (PPM) typically occurs after the period of most rapid growth, and production is regulated in a quorum sensing (QS)-dependent manner. PA1201 contains two PCA biosynthetic gene clusters phz1 and phz2; both clusters contribute to PCA production, with phz2 making a greater contribution. PA1201 also contains a complete set of genes for four QS systems (LasI/LasR, RhlI/RhlR, PQS/MvfR, and IQS). By using several methods including gene deletion, the construction of promoter-lacZ fusion reporter strains, and RNA-Seq analysis, this study investigated the effects of the four QS systems on bacterial growth, QS signal production, the expression of phz1 and phz2, and PCA production. The possible mechanisms for the strain- and condition-dependent expression of phz1 and phz2 were discussed, and a schematic model was proposed. These findings provide a basis for further genetic engineering of the QS systems to improve PCA production. PMID:27456813

  12. Draft Genome Sequence of a Diazotrophic, Plant Growth-Promoting Rhizobacterium of the Pseudomonas syringae Complex.

    PubMed

    Patten, Cheryl L; Jeong, Haeyoung; Blakney, Andrew J C; Wallace, Natalie

    2016-01-01

    We report here the draft genome sequence of Pseudomonas syringae GR12-2, a nitrogen-fixing, plant growth-promoting bacterium, isolated from the rhizosphere of an Arctic grass. The 6.6-Mbp genome contains 5,676 protein-coding genes, including a nitrogen-fixation island similar to that in P. stutzeri. PMID:27660794

  13. Draft Genome Sequence of a Diazotrophic, Plant Growth–Promoting Rhizobacterium of the Pseudomonas syringae Complex

    PubMed Central

    Jeong, Haeyoung; Blakney, Andrew J. C.; Wallace, Natalie

    2016-01-01

    We report here the draft genome sequence of Pseudomonas syringae GR12-2, a nitrogen-fixing, plant growth–promoting bacterium, isolated from the rhizosphere of an Arctic grass. The 6.6-Mbp genome contains 5,676 protein-coding genes, including a nitrogen-fixation island similar to that in P. stutzeri. PMID:27660794

  14. The RNA Chaperone Hfq Regulates Antibiotic Biosynthesis in the Rhizobacterium Pseudomonas aeruginosa M18

    PubMed Central

    Wang, Guohao; Li, Sainan; Huang, Jiaofang; Wei, Xue; Li, Yaqian

    2012-01-01

    The rhizosphere microbe Pseudomonas aeruginosa M18 shows strong antifungal activities, mainly due to the biosynthesis of antibiotics like pyoluteorin (Plt) and phenazine-1-carboxylic acid (PCA). The ubiquitous RNA chaperone Hfq regulates bacterial virulence and stress tolerance through global posttranscriptional regulation. Here, we explored the molecular mechanism by which Hfq controls antibiotic biosynthesis in P. aeruginosa M18. The robust downregulation of Plt biosynthesis by Hfq was mediated exclusively by the posttranscriptional downregulation of the plt transcriptional activator PltR. Hfq posttranscriptionally repressed phzM expression and consequently reduced the conversion of PCA to pyocyanin. However, Hfq positively controlled the phz2 operon and PCA biosynthesis through both QscR-mediated transcriptional regulation at the promoter and an unknown regulation at the operator. Also, Hfq was shown to directly bind at the mRNA 5′ untranslated leaders of pltR, qscR, and phzM. These three negatively regulated target genes of Hfq shared a similar secondary structure with a short single-stranded AU-rich spacer (a potential Hfq-binding motif) linking two stem-loops. Taken together, these results indicate that Hfq, potentially in collaboration with unknown small noncoding RNAs (sRNAs), tightly controls antibiotic biosynthesis through both direct posttranscriptional inhibition and indirect transcriptional regulation. PMID:22427627

  15. Genome Analysis of Pseudomonas fluorescens PCL1751: A Rhizobacterium that Controls Root Diseases and Alleviates Salt Stress for Its Plant Host

    PubMed Central

    Cho, Shu-Ting; Chang, Hsing-Hua; Egamberdieva, Dilfuza; Kamilova, Faina; Lugtenberg, Ben; Kuo, Chih-Horng

    2015-01-01

    Pseudomonas fluorescens PCL1751 is a rod-shaped Gram-negative bacterium isolated from the rhizosphere of a greenhouse-grown tomato plant in Uzbekistan. It controls several plant root diseases caused by Fusarium fungi through the mechanism of competition for nutrients and niches (CNN). This mechanism does not rely on the production of antibiotics, so it avoids the concerns of resistance development and is environmentally safe. Additionally, this bacterium promotes plant growth by alleviating salt stress for its plant host. To investigate the genetic mechanisms that may explain these observations, we determined the complete genome sequence of this bacterium, examined its gene content, and performed comparative genomics analysis with other Pseudomonas strains. The genome of P. fluorescens PCL1751 consisted of one circular chromosome that is 6,143,950 base-pairs (bp) in size; no plasmid was found. The annotation included 19 rRNA, 70 tRNA, and 5,534 protein-coding genes. The gene content analysis identified a large number of genes involved in chemotaxis and motility, colonization of the rhizosphere, siderophore biosynthesis, and osmoprotectant production. In contrast, the pathways involved in the biosynthesis of phytohormones or antibiotics were not found. Comparison with other Pseudomonas genomes revealed extensive variations in their genome size and gene content. The presence and absence of secretion system genes were highly variable. As expected, the synteny conservation among strains decreased as a function of phylogenetic divergence. The integration of prophages appeared to be an important driver for genome rearrangements. The whole-genome gene content analysis of this plant growth-promoting rhizobacterium (PGPR) provided some genetic explanations to its phenotypic characteristics. The extensive and versatile substrate utilization pathways, together with the presence of many genes involved in competitive root colonization, provided further support for the finding

  16. Genome Analysis of Pseudomonas fluorescens PCL1751: A Rhizobacterium that Controls Root Diseases and Alleviates Salt Stress for Its Plant Host.

    PubMed

    Cho, Shu-Ting; Chang, Hsing-Hua; Egamberdieva, Dilfuza; Kamilova, Faina; Lugtenberg, Ben; Kuo, Chih-Horng

    2015-01-01

    Pseudomonas fluorescens PCL1751 is a rod-shaped Gram-negative bacterium isolated from the rhizosphere of a greenhouse-grown tomato plant in Uzbekistan. It controls several plant root diseases caused by Fusarium fungi through the mechanism of competition for nutrients and niches (CNN). This mechanism does not rely on the production of antibiotics, so it avoids the concerns of resistance development and is environmentally safe. Additionally, this bacterium promotes plant growth by alleviating salt stress for its plant host. To investigate the genetic mechanisms that may explain these observations, we determined the complete genome sequence of this bacterium, examined its gene content, and performed comparative genomics analysis with other Pseudomonas strains. The genome of P. fluorescens PCL1751 consisted of one circular chromosome that is 6,143,950 base-pairs (bp) in size; no plasmid was found. The annotation included 19 rRNA, 70 tRNA, and 5,534 protein-coding genes. The gene content analysis identified a large number of genes involved in chemotaxis and motility, colonization of the rhizosphere, siderophore biosynthesis, and osmoprotectant production. In contrast, the pathways involved in the biosynthesis of phytohormones or antibiotics were not found. Comparison with other Pseudomonas genomes revealed extensive variations in their genome size and gene content. The presence and absence of secretion system genes were highly variable. As expected, the synteny conservation among strains decreased as a function of phylogenetic divergence. The integration of prophages appeared to be an important driver for genome rearrangements. The whole-genome gene content analysis of this plant growth-promoting rhizobacterium (PGPR) provided some genetic explanations to its phenotypic characteristics. The extensive and versatile substrate utilization pathways, together with the presence of many genes involved in competitive root colonization, provided further support for the finding

  17. Low temperature growth, freezing survival, and production of antifreeze protein by the plant growth promoting rhizobacterium Pseudomonas putida GR12-2.

    PubMed

    Sun, X; Griffith, M; Pasternak, J J; Glick, B R

    1995-09-01

    The plant growth promoting rhizobacterium Pseudomonas putida GR12-2 was originally isolated from the rhizosphere of plants growing in the Canadian High Arctic. Here we report that this bacterium was able to grow and promote root elongation of both spring and winter canola at 5 degrees C, a temperature at which only a relatively small number of bacteria are able to proliferate and function. In addition, the bacterium survived exposure to freezing temperatures, i.e., -20 and -50 degrees C. In an effort to determine the mechanistic basis for this behaviour, it was discovered that following growth at 5 degrees C, P. putida GR12-2 synthesized and secreted to the growth medium a protein with antifreeze activity. Analysis of the spent growth medium, following concentration by ultrafiltration, by SDS-polyacrylamide gel electrophoresis revealed the presence of one major protein with a molecular mass of approximately 32-34 kDa and a number of minor proteins. However, at this point it is not known which of these proteins contains the antifreeze activity. PMID:7585354

  18. Global control of GacA in secondary metabolism, primary metabolism, secretion systems, and motility in the rhizobacterium Pseudomonas aeruginosa M18.

    PubMed

    Wei, Xue; Huang, Xianqing; Tang, Lulu; Wu, Daqiang; Xu, Yuquan

    2013-08-01

    The rhizobacterium Pseudomonas aeruginosa M18 can produce a broad spectrum of secondary metabolites, including the antibiotics pyoluteorin (Plt) and phenazine-1-carboxylic acid (PCA), hydrogen cyanide, and the siderophores pyoverdine and pyochelin. The antibiotic biosynthesis of M18 is coordinately controlled by multiple distinct regulatory pathways, of which the GacS/GacA system activates Plt biosynthesis but strongly downregulates PCA biosynthesis. Here, we investigated the global influence of a gacA mutation on the M18 transcriptome and related metabolic and physiological processes. Transcriptome profiling revealed that the transcript levels of 839 genes, which account for approximately 15% of the annotated genes in the M18 genome, were significantly influenced by the gacA mutation during the early stationary growth phase of M18. Most secondary metabolic gene clusters, such as pvd, pch, plt, amb, and hcn, were activated by GacA. The GacA regulon also included genes encoding extracellular enzymes and cytochrome oxidases. Interestingly, the primary metabolism involved in the assimilation and metabolism of phosphorus, sulfur, and nitrogen sources was also notably regulated by GacA. Another important category of the GacA regulon was secretion systems, including H1, H2, and H3 (type VI secretion systems [T6SSs]), Hxc (T2SS), and Has and Apr (T1SSs), and CupE and Tad pili. More remarkably, GacA inhibited swimming, swarming, and twitching motilities. Taken together, the Gac-initiated global regulation, which was mostly mediated through multiple regulatory systems or factors, was mainly involved in secondary and primary metabolism, secretion systems, motility, etc., contributing to ecological or nutritional competence, ion homeostasis, and biocontrol in M18. PMID:23708134

  19. Characterization of a phage-like pyocin from the plant growth-promoting rhizobacterium Pseudomonas fluorescens SF4c.

    PubMed

    Fischer, Sonia; Godino, Agustina; Quesada, José Miguel; Cordero, Paula; Jofré, Edgardo; Mori, Gladys; Espinosa-Urgel, Manuel

    2012-06-01

    R-type and F-type pyocins are high-molecular-mass bacteriocins produced by Pseudomonas aeruginosa that resemble bacteriophage tails. They contain no head structures and no DNA, and are used as defence systems. In this report, we show that Pseudomonas fluorescens SF4c, a strain isolated from the wheat rhizosphere, produces a high-molecular-mass bacteriocin which inhibits the growth of closely related bacteria. A mutant deficient in production of this antimicrobial compound was obtained by transposon mutagenesis. Sequence analysis revealed that the transposon had disrupted a gene that we have named ptm, since it is homologous to that encoding phage tape-measure protein in P. fluorescens Pf0-1, a gene belonging to a prophage similar to phage-like pyocin from P. aeruginosa PAO1. In addition, we have identified genes from the SF4c pyocin cluster that encode a lytic system and regulatory genes. We constructed a non-polar ptm mutant of P. fluorescens SF4c. Heterologous complementation of this mutation restored the production of bacteriocin. Real-time PCR was used to analyse the expression of pyocin under different stress conditions. Bacteriocin was upregulated by mitomycin C, UV light and hydrogen peroxide, and was downregulated by saline stress. This report constitutes, to our knowledge, the first genetic characterization of a phage tail-like bacteriocin in a rhizosphere Pseudomonas strain.

  20. Metabolic and Transcriptomic Changes Induced in Arabidopsis by the Rhizobacterium Pseudomonas fluorescens SS1011[W][OA

    PubMed Central

    van de Mortel, Judith E.; de Vos, Ric C.H.; Dekkers, Ester; Pineda, Ana; Guillod, Leandre; Bouwmeester, Klaas; van Loon, Joop J.A.; Dicke, Marcel; Raaijmakers, Jos M.

    2012-01-01

    Systemic resistance induced in plants by nonpathogenic rhizobacteria is typically effective against multiple pathogens. Here, we show that root-colonizing Pseudomonas fluorescens strain SS101 (Pf.SS101) enhanced resistance in Arabidopsis (Arabidopsis thaliana) against several bacterial pathogens, including Pseudomonas syringae pv tomato (Pst) and the insect pest Spodoptera exigua. Transcriptomic analysis and bioassays with specific Arabidopsis mutants revealed that, unlike many other rhizobacteria, the Pf.SS101-induced resistance response to Pst is dependent on salicylic acid signaling and not on jasmonic acid and ethylene signaling. Genome-wide transcriptomic and untargeted metabolomic analyses showed that in roots and leaves of Arabidopsis plants treated with Pf.SS101, approximately 1,910 genes and 50 metabolites were differentially regulated relative to untreated plants. Integration of both sets of “omics” data pointed to a prominent role of camalexin and glucosinolates in the Pf.SS101-induced resistance response. Subsequent bioassays with seven Arabidopsis mutants (myb51, cyp79B2cyp79B3, cyp81F2, pen2, cyp71A12, cyp71A13, and myb28myb29) disrupted in the biosynthesis pathways for these plant secondary metabolites showed that camalexin and glucosinolates are indeed required for the induction of Pst resistance by Pf.SS101. Also for the insect S. exigua, the indolic glucosinolates appeared to play a role in the Pf.SS101-induced resistance response. This study provides, to our knowledge for the first time, insight into the substantial biochemical and temporal transcriptional changes in Arabidopsis associated with the salicylic acid-dependent resistance response induced by specific rhizobacteria. PMID:23073694

  1. Fluorescent Pseudomonas Strains with only Few Plant-Beneficial Properties Are Favored in the Maize Rhizosphere

    PubMed Central

    Vacheron, Jordan; Moënne-Loccoz, Yvan; Dubost, Audrey; Gonçalves-Martins, Maximilien; Muller, Daniel; Prigent-Combaret, Claire

    2016-01-01

    Plant Growth-Promoting Rhizobacteria (PGPR) enhance plant health and growth using a variety of traits. Effective PGPR strains typically exhibit multiple plant-beneficial properties, but whether they are better adapted to the rhizosphere than PGPR strains with fewer plant-beneficial properties is unknown. Here, we tested the hypothesis that strains with higher numbers of plant-beneficial properties would be preferentially selected by plant roots. To this end, the co-occurrence of 18 properties involved in enhanced plant nutrition, plant hormone modulation, or pathogen inhibition was analyzed by molecular and biochemical methods in a collection of maize rhizosphere and bulk soil isolates of fluorescent Pseudomonas. Twelve plant-beneficial properties were found among the 698 isolates. Contrarily to expectation, maize preferentially selected pseudomonads with low numbers of plant-beneficial properties (up to five). This selection was not due to the predominance of strains with specific assortments of these properties, or with specific taxonomic status. Therefore, the occurrence of only few plant-beneficial properties appeared favorable for root colonization by pseudomonads. PMID:27610110

  2. Fluorescent Pseudomonas Strains with only Few Plant-Beneficial Properties Are Favored in the Maize Rhizosphere

    PubMed Central

    Vacheron, Jordan; Moënne-Loccoz, Yvan; Dubost, Audrey; Gonçalves-Martins, Maximilien; Muller, Daniel; Prigent-Combaret, Claire

    2016-01-01

    Plant Growth-Promoting Rhizobacteria (PGPR) enhance plant health and growth using a variety of traits. Effective PGPR strains typically exhibit multiple plant-beneficial properties, but whether they are better adapted to the rhizosphere than PGPR strains with fewer plant-beneficial properties is unknown. Here, we tested the hypothesis that strains with higher numbers of plant-beneficial properties would be preferentially selected by plant roots. To this end, the co-occurrence of 18 properties involved in enhanced plant nutrition, plant hormone modulation, or pathogen inhibition was analyzed by molecular and biochemical methods in a collection of maize rhizosphere and bulk soil isolates of fluorescent Pseudomonas. Twelve plant-beneficial properties were found among the 698 isolates. Contrarily to expectation, maize preferentially selected pseudomonads with low numbers of plant-beneficial properties (up to five). This selection was not due to the predominance of strains with specific assortments of these properties, or with specific taxonomic status. Therefore, the occurrence of only few plant-beneficial properties appeared favorable for root colonization by pseudomonads.

  3. Fluorescent Pseudomonas Strains with only Few Plant-Beneficial Properties Are Favored in the Maize Rhizosphere.

    PubMed

    Vacheron, Jordan; Moënne-Loccoz, Yvan; Dubost, Audrey; Gonçalves-Martins, Maximilien; Muller, Daniel; Prigent-Combaret, Claire

    2016-01-01

    Plant Growth-Promoting Rhizobacteria (PGPR) enhance plant health and growth using a variety of traits. Effective PGPR strains typically exhibit multiple plant-beneficial properties, but whether they are better adapted to the rhizosphere than PGPR strains with fewer plant-beneficial properties is unknown. Here, we tested the hypothesis that strains with higher numbers of plant-beneficial properties would be preferentially selected by plant roots. To this end, the co-occurrence of 18 properties involved in enhanced plant nutrition, plant hormone modulation, or pathogen inhibition was analyzed by molecular and biochemical methods in a collection of maize rhizosphere and bulk soil isolates of fluorescent Pseudomonas. Twelve plant-beneficial properties were found among the 698 isolates. Contrarily to expectation, maize preferentially selected pseudomonads with low numbers of plant-beneficial properties (up to five). This selection was not due to the predominance of strains with specific assortments of these properties, or with specific taxonomic status. Therefore, the occurrence of only few plant-beneficial properties appeared favorable for root colonization by pseudomonads. PMID:27610110

  4. Unraveling Root Developmental Programs Initiated by Beneficial Pseudomonas spp. Bacteria1[C][W][OA

    PubMed Central

    Zamioudis, Christos; Mastranesti, Parthena; Dhonukshe, Pankaj; Blilou, Ikram; Pieterse, Corné 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 the most abundant genera of the root microbiome. Here, by employing a germ-free experimental system, we demonstrate the ability of selected Pseudomonas spp. strains to promote plant growth and drive developmental plasticity in the roots of Arabidopsis (Arabidopsis thaliana) by inhibiting primary root elongation and promoting lateral root and root hair formation. By studying cell type-specific developmental markers and employing genetic and pharmacological approaches, we demonstrate the crucial role of auxin signaling and transport in rhizobacteria-stimulated changes in the root system architecture of Arabidopsis. We further show that Pseudomonas spp.-elicited alterations in root morphology and rhizobacteria-mediated systemic immunity are mediated by distinct signaling pathways. This study sheds new light on the ability of soil-borne beneficial bacteria to interfere with postembryonic root developmental programs. PMID:23542149

  5. Cost of Adaptation and Fitness Effects of Beneficial Mutations in Pseudomonas fluorescens

    PubMed Central

    Bataillon, Thomas; Zhang, Tianyi; Kassen, Rees

    2011-01-01

    Adaptations are constructed through the sequential substitution of beneficial mutations by natural selection. However, the rarity of beneficial mutations has precluded efforts to describe even their most basic properties. Do beneficial mutations typically confer small or large fitness gains? Are their fitness effects environment specific, or are they broadly beneficial across a range of environments? To answer these questions, we used two subsets (n = 18 and n = 63) of a large library of mutants carrying antibiotic resistance mutations in the bacterium Pseudomonas fluorescens whose fitness, along with the antibiotic sensitive ancestor, was assayed across 95 novel environments differing in the carbon source available for growth. We explore patterns of genotype-by-environment (G×E) interactions and ecological specialization among the 18 mutants initially found superior to the sensitive ancestor in one environment. We find that G×E is remarkably similar between the two sets of mutants and that beneficial mutants are not typically associated with large costs of adaptation. Fitness effects among beneficial mutants depart from a strict exponential distribution: they assume a variety of shapes that are often roughly L shaped but always right truncated. Distributions of (beneficial) fitness effects predicted by a landscape model assuming multiple traits underlying fitness and a single optimum often provide a good description of the empirical distributions in our data. Simulations of data sets containing a mixture of single and double mutants under this landscape show that inferences about the distribution of fitness effects of beneficial mutants is quite robust to contamination by second-site mutations. PMID:21868607

  6. Gibberellin secreting rhizobacterium, Pseudomonas putida H-2-3 modulates the hormonal and stress physiology of soybean to improve the plant growth under saline and drought conditions.

    PubMed

    Kang, Sang-Mo; Radhakrishnan, Ramalingam; Khan, Abdul Latif; Kim, Min-Ji; Park, Jae-Man; Kim, Bo-Ra; Shin, Dong-Hyun; Lee, In-Jung

    2014-11-01

    The physiological changes in tolerant soybean plants under salt and drought stress conditions with Pseudomonas putida H-2-3 were investigated. A bacterial isolate H-2-3 was isolated from soil and identified as Pseudomonas putida H-2-3 by 16S rDNA sequences. The treatment of P. putida H-2-3 significantly increased the length, fresh and dry weight of shoot and chlorophyll content in gibberellins (GAs) deficient mutant Waito-c rice seedlings over the control, it might be the presence of GA1, GA4, GA9 and GA20. The soybean plant growth was retarded in salt (120 mM sodium chloride) and drought (15% polyethylene glycol) stress conditions at 10 days treatments, while P. putida H-2-3 effectively enhanced the shoot length and fresh weight of plants suffered at salt and drought stress. The chlorophyll content was lower in abiotic stress conditions and bacterial inoculant P. putida H-2-3 mitigated the stress effects by an evidence of higher quantity of chlorophyll content in plants exposed to salt and drought. The stress hormonal analysis revealed that individual treatment of P. putida H-2-3, salt and drought significantly enhanced the abscisic acid and salicylic acid content than their control. P. putida H-2-3 applied to salt and drought stressed plants showed a lower level of abscisic acid and salicylic acid and a higher level of jasmonic acid content. Under stress condition induced by salt and drought in plants expressed higher level of total polyphenol, superoxide dismutase and radical scavenging activity and no significant changes in flavonoids. The bio-inoculant, P. putida H-2-3 modulated those antioxidants by declining superoxide dismutase, flavonoids and radical scavenging activity. P. putida H-2-3 induced tolerance against abiotic stress was confirmed by a reduction of Na content in abiotic stressed plants. The results suggest that P. putida H-2-3 application reprograms the chlorophyll, stress hormones and antioxidants expression in abiotic stress affected

  7. The RpoS Sigma Factor Negatively Regulates Production of IAA and Siderophore in a Biocontrol Rhizobacterium, Pseudomonas chlororaphis O6.

    PubMed

    Oh, Sang A; Kim, Ji Soo; Park, Ju Yeon; Han, Song Hee; Dimkpa, Christian; Anderson, Anne J; Kim, Young Cheol

    2013-09-01

    The stationary-phase sigma factor, RpoS, influences the expression of factors important in survival of Pseudomonas chlororaphis O6 in the rhizosphere. A partial proteomic profile of a rpoS mutant in P. chlororaphis O6 was conducted to identify proteins under RpoS regulation. Five of 14 differentially regulated proteins had unknown roles. Changes in levels of proteins in P. chlororaphis O6 rpoS mutant were associated with iron metabolism, and protection against oxidative stress. The P. chlororaphis O6 rpoS mutant showed increased production of a pyoverdine-like siderophore, indole acetic acid, and altered isozyme patterns for peroxidase, catalase and superoxide dismutase. Consequently, sensitivity to hydrogen peroxide exposure increased in the P. chlororaphis O6 rpoS mutant, compared with the wild type. Taken together, RpoS exerted regulatory control over factors important for the habitat of P. chlororaphis O6 in soil and on root surfaces. The properties of several of the proteins in the RpoS regulon are currently unknown. PMID:25288959

  8. Expression and characterization of 1-aminocyclopropane-1-carboxylate deaminase from the rhizobacterium Pseudomonas putida UW4: a key enzyme in bacterial plant growth promotion.

    PubMed

    Hontzeas, Nikos; Zoidakis, Jérôme; Glick, Bernard R; Abu-Omar, Mahdi M

    2004-12-01

    The enzyme 1-aminocyclopropane-1-carboxylate deaminase (ACCD) converts ACC, the precursor of the plant hormone ethylene, to alpha-ketobutyrate and ammonium. This enzyme has been identified in soil bacteria and has been proposed to play a key role in microbe-plant association. A soluble recombinant ACCD from Pseudomonas putida UW4 of molecular weight 41 kDa has been cloned, expressed, and purified. It showed selectivity and high activity towards the substrate ACC: K(M)=3.4+/-0.2 mM and k(cat)=146+/-5 min(-1) at pH 8.0 and 22 degrees C. The enzyme displayed optimal activity at pH 8.0 with a sharp decline to essentially no activity below pH 6.5 and a slightly less severe tapering in activity at higher pH resulting in loss of activity at pH>10. The major component of the enzyme's secondary structure was determined to be alpha-helical by circular dichroism (CD). P. putida UW4 ACCD unfolded at 60 degrees C as determined by its CD temperature profile as well as by differential scanning microcalorimetry (DSC). Enzyme activity was knocked out in the point mutant Gly44Asp. Modeling this mutation into the known yeast ACCD structure shed light on the role this highly conserved residue plays in allowing substrate accessibility to the active site. This enzyme's biochemical and biophysical properties will serve as an important reference point to which newly isolated ACC deaminases from other organisms can be compared. PMID:15588698

  9. Plant growth promoting rhizobacterium

    SciTech Connect

    Doktycz, Mitchel John; Pelletier, Dale A.; Schadt, Christopher Warren; Tuskan, Gerald A.; Weston, David

    2015-08-11

    The present invention is directed to the Pseudomonas fluorescens strain GM30 deposited under ATCC Accession No. PTA-13340, compositions containing the GM30 strain, and methods of using the GM30 strain to enhance plant growth and/or enhance plant resistance to pathogens.

  10. Toxic effect of environmentally relevant concentration of silver nanoparticles on environmentally beneficial bacterium Pseudomonas putida.

    PubMed

    Khan, S Sudheer; Ghouse, Syed Shabin; Chandran, Preethy

    2015-07-01

    Silver nanoparticles (Ag NPs) are being increasingly used in many consumer products owing to their excellent antimicrobial properties. The continuous use of Ag NPs in consumer products will lead to environmental release. The present study evaluated the toxic effects and the possible underlying mechanism of Ag NPs on Pseudomonas putida. Ag NP exposure inhibited growth of the cells. Increased lipid peroxidation occurred coincident with suppression of the antioxidant defense system. Ag NP exposure caused reactive oxygen species (ROS) production, glutathione depletion and inactivation of the antioxidant enzyme superoxide dismutase, catalase and glutathione reductase. The addition of superoxide dismutase or pretreatment of P. putida with N-acetyl cysteine that quenches ROS reduced toxicity of the NPs. PMID:25627470

  11. Comparative analysis of defence responses induced by the endophytic plant growth-promoting rhizobacterium Burkholderia phytofirmans strain PsJN and the non-host bacterium Pseudomonas syringae pv. pisi in grapevine cell suspensions.

    PubMed

    Bordiec, Sophie; Paquis, Sandra; Lacroix, Hélène; Dhondt, Sandrine; Ait Barka, Essaïd; Kauffmann, Serge; Jeandet, Philippe; Mazeyrat-Gourbeyre, Florence; Clément, Christophe; Baillieul, Fabienne; Dorey, Stéphan

    2011-01-01

    Plant growth-promoting rhizobacteria (PGPR) are beneficial microorganisms that colonize the rhizosphere of many plant species and confer beneficial effects, such as an increase in plant growth. PGPR are also well known as inducers of systemic resistance to pathogens in plants. However, the molecular mechanisms involved locally after direct perception of these bacteria by plant cells still remain largely unknown. Burkholderia phytofirmans strain PsJN is an endophytic PGPR that colonizes grapevine and protects the plant against the grey mould disease caused by Botrytis cinerea. This report focuses on local defence events induced by B. phytofirmans PsJN after perception by the grapevine cells. It is demonstrated that, after addition to cell suspension cultures, the bacteria were tightly attaching to plant cells in a way similar to the grapevine non-host bacteria Pseudomonas syringae pv. pisi. B. phytofirmans PsJN perception led to a transient and monophasic extracellular alkalinization but no accumulation of reactive oxygen species or cell death were detected. By contrast, challenge with P. syringae pv. pisi induced a sustained and biphasic extracellular alkalinization, a two phases oxidative burst, and a HR-like response. Perception of the PGPR also led to the production of salicylic acid (SA) and the expression of a battery of defence genes that was, however, weaker in intensity compared with defence gene expression triggered by the non-host bacteria. Some defence genes up-regulated after B. phytofirmans PsJN challenge are specifically induced by exogenous treatment with SA or jasmonic acid, suggesting that both signalling pathways are activated by the PGPR in grapevine.

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

    PubMed

    Setten, Lorena; Soto, Gabriela; Mozzicafreddo, Matteo; Fox, Ana Romina; Lisi, Christian; Cuccioloni, Massimiliano; Angeletti, Mauro; Pagano, Elba; Díaz-Paleo, Antonio; Ayub, Nicolás Daniel

    2013-01-01

    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.

  13. Engineering Pseudomonas protegens Pf-5 for Nitrogen Fixation and its Application to Improve Plant Growth under Nitrogen-Deficient Conditions

    PubMed Central

    Setten, Lorena; Soto, Gabriela; Mozzicafreddo, Matteo; Fox, Ana Romina; Lisi, Christian; Cuccioloni, Massimiliano; Angeletti, Mauro; Pagano, Elba; Díaz-Paleo, Antonio; Ayub, Nicolás Daniel

    2013-01-01

    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. PMID:23675499

  14. Structural characterization of the O-chain polysaccharide from an environmentally beneficial bacterium Pseudomonas chlororaphis subsp. aureofaciens strain M71.

    PubMed

    Pieretti, Giuseppina; Puopolo, Gerardo; Carillo, Sara; Zoina, Astolfo; Lanzetta, Rosa; Parrilli, Michelangelo; Evidente, Antonio; Corsaro, Maria Michela

    2011-12-13

    Pseudomonas chlororaphis subsp. aureofaciens strain M71 was isolated from the root of a tomato plant and it was able to control in vivo Fusarium oxysporum f. sp. radicis-lycopersici responsible for the tomato crown and root rot. Recently, strain M71 was evaluated even for its efficacy in controlling Seiridium cardinale, the causal agent of bark canker of common cypress (Cupressus sempervirens L.). Strain M71 ability to persist on the tomato rhizosphere and on the aerial part of cypress plants could be related to the nature of the lipopolysaccharides (LPS) present on the outer membrane and in particular to the O-specific polysaccharide. A neutral O-specific polysaccharide was obtained by mild acid hydrolysis of the lipopolysaccharide from P. chlororaphis subsp. aureofaciens strain M71. By means of compositional analyses and NMR spectroscopy, the chemical repeating unit of the polymer was identified as the following linear trisaccharide.

  15. Complete Genome Sequence of Biocontrol Strain Pseudomonas fluorescens LBUM 223

    PubMed Central

    Roquigny, Roxane; Arseneault, Tanya; Gadkar, Vijay J.; Novinscak, Amy

    2015-01-01

    Pseudomonas fluorescens LBUM 223 is a plant growth-promoting rhizobacterium (PGPR) with biocontrol activity against various plant pathogens. It produces the antimicrobial metabolite phenazine-1-carboxylic acid, which is involved in the biocontrol of Streptomyces scabies, the causal agent of common scab of potato. Here, we report the complete genome sequence of P. fluorescens LBUM 223. PMID:25953163

  16. Complete Genome Sequence of Biocontrol Strain Pseudomonas fluorescens LBUM223

    PubMed Central

    Roquigny, Roxane; Arseneault, Tanya; Gadkar, Vijay J.; Novinscak, Amy

    2015-01-01

    Pseudomonas fluorescens LBUM223 is a plant growth-promoting rhizobacterium (PGPR) with biocontrol activity against various plant pathogens. It produces the antimicrobial metabolite phenazine-1-carboxylic acid, which is involved in the biocontrol of Streptomyces scabies, the causal agent of common scab of potato. Here, we report the complete genome sequence of P. fluorescens LBUM223. PMID:25953163

  17. Priming by Rhizobacterium Protects Tomato Plants from Biotrophic and Necrotrophic Pathogen Infections through Multiple Defense Mechanisms

    PubMed Central

    Ahn, Il-Pyung; Lee, Sang-Woo; Kim, Min Gab; Park, Sang-Ryeol; Hwang, Duk-Ju; Bae, Shin-Chul

    2011-01-01

    A selected strain of rhizobacterium, Pseudomonas putida strain LSW17S (LSW17S), protects tomato plants (Lycopersicon esculentum L. cv. Seokwang) from bacterial speck by biotrophic Pseudomonas syringae pv. tomato strain DC3000 (DC3000) and bacterial wilt by necrotrophic Ralstonia solanacearum KACC 10703 (Rs10703). To investigate defense mechanisms induced by LSW17S in tomato plants, transcription patterns of pathogenesis-related (PR) genes and H2O2 production were analyzed in plants treated with LSW17S and subsequent pathogen inoculation. LSW17S alone did not induce transcriptions of employed PR genes in leaves and roots. DC3000 challenge following LSW17S triggered rapid transcriptions of PR genes and H2O2 production in leaves and roots. Catalase infiltration with DC3000 attenuated defense-related responses and resistance against DC3000 infection. Despite depriving H2O2 production and PR1b transcription by the same treatment, resistance against Rs10703 infection was not deterred significantly. H2O2 is indispensable for defense signaling and/or mechanisms primed by LSW17S and inhibition of bacterial speck, however, it is not involved in resistance against bacterial wilt. PMID:21710203

  18. Genome Sequence of the Biocontrol Strain Pseudomonas fluorescens F113

    PubMed Central

    Redondo-Nieto, Miguel; Barret, Matthieu; Morrisey, John P.; Germaine, Kieran; Martínez-Granero, Francisco; Barahona, Emma; Navazo, Ana; Sánchez-Contreras, María; Moynihan, Jennifer A.; Giddens, Stephen R.; Coppoolse, Eric R.; Muriel, Candela; Stiekema, Willem J.; Rainey, Paul B.; Dowling, David; O'Gara, Fergal; Martín, Marta

    2012-01-01

    Pseudomonas fluorescens F113 is a plant growth-promoting rhizobacterium (PGPR) that has biocontrol activity against fungal plant pathogens and is a model for rhizosphere colonization. Here, we present its complete genome sequence, which shows that besides a core genome very similar to those of other strains sequenced within this species, F113 possesses a wide array of genes encoding specialized functions for thriving in the rhizosphere and interacting with eukaryotic organisms. PMID:22328765

  19. Complete Genome Sequence of Pseudomonas fluorescens LBUM636, a Strain with Biocontrol Capabilities against Late Blight of Potato

    PubMed Central

    Morrison, Christopher K.; Novinscak, Amy; Gadkar, Vijay J.; Joly, David L.

    2016-01-01

    Herein provided is the full-genome sequence of Pseudomonas fluorescens LBUM636. This strain is a plant growth-promoting rhizobacterium (PGPR) which produces phenazine-1-carboxylic acid, an antibiotic involved in the biocontrol of numerous plant pathogens, including late blight of potato caused by the plant pathogen Phytophthora infestans. PMID:27231373

  20. GacS-dependent production of 2R, 3R-butanediol by Pseudomonas chlororaphis O6 is a major determinant for eliciting systemic resistance against Erwinia carotovora but not against Pseudomonas syringae pv. tabaci in tobacco.

    PubMed

    Han, Song Hee; Lee, Seung Je; Moon, Jae Hak; Park, Keun Hyung; Yang, Kwang Yeol; Cho, Balk Ho; Kim, Kil Yong; Kim, Yong Whan; Lee, Myung Chul; Anderson, Anne J; Kim, Young Cheol

    2006-08-01

    Root colonization by a plant-beneficial rhizobacterium, Pseudomonas chlororaphis O6, induces disease resistance in tobacco against leaf pathogens Erwinia carotovora subsp. carotovora SCC1, causing soft-rot, and Pseudomonas syringae pv. tabaci, causing wildfire. In order to identify the bacterial determinants involved in induced systemic resistance against plant diseases, extracellular components produced by the bacterium were fractionated and purified. Factors in the culture filtrate inducing systemic resistance were retained in the aqueous fraction rather than being partitioned into ethyl acetate. Fractionation on high-performance liquid chromatography followed by nuclear magnetic resonance mass spectrometry analysis identified the active compound as 2R, 3R-butanediol. 2R, 3R butanediol induced systemic resistance in tobacco to E. carotovora subsp. carotovora SCC1, but not to P. syringae pv. tabaci. Treatment of tobacco with the volatile 2R, 3R-butanediol enhanced aerial growth, a phenomenon also seen in plants colonized by P. chlororaphis O6. The isomeric form of the butanediol was important because 2S, 3S-butandiol did not affect the plant. The global sensor kinase, GacS, of P. chlororaphis O6 was a key regulator for induced systemic resistance against E. carotovora through regulation of 2R, 3R-butanediol production. This is the first report of the production of these assumed fermentation products by a pseudomonad and the role of the sensor kinase GacS in production of 2R, 3R-butanediol. PMID:16903358

  1. Synergy between Glomus fasciculatum and a beneficial Pseudomonas in reducing root diseases and improving yield and forskolin content in Coleus forskohlii Briq. under organic field conditions.

    PubMed

    Singh, Rakshapal; Soni, Sumit K; Kalra, Alok

    2013-01-01

    Root rot and wilt, caused by a complex involving Fusarium chlamydosporum (Frag. and Cif.) and Ralstonia solanacearum (Smith), are serious diseases affecting the cultivation of Coleus forskohlii, a crop with economic potential as a source of the medicinal compound forskolin. The present 2-year field experiments were conducted with two bioinoculants (a native Pseudomonas monteilii strain and the exotic arbuscular mycorrhizal (AM) fungus Glomus fasciculatum) alone and in combination under organic field conditions in order to evaluate their potential in controlling root rot and wilt. Combined inoculation of P. monteilii with G. fasciculatum significantly increased plant height, plant spread, and number of branches; reduced disease incidence; and increased tuber dry mass of C. forskohlii, compared to vermicompost controls not receiving any bioinoculants. Increase in tuber yields was accompanied by an increase in plant N, P, and K uptake. Co-inoculation of P. monteilii with G. fasciculatum significantly improved the percent AM root colonization and spore numbers retrieved from soil. This suggests P. monteilii to be a mycorrhiza helper bacterium which could be useful in organic agriculture. The forskolin content of tubers was significantly increased by the inoculation treatments of P. monteilii, G. fasciculatum, and P. monteilii + G. fasciculatum.

  2. The rhizobacterium Arthrobacter agilis produces dimethylhexadecylamine, a compound that inhibits growth of phytopathogenic fungi in vitro.

    PubMed

    Velázquez-Becerra, Crisanto; Macías-Rodríguez, Lourdes I; López-Bucio, José; Flores-Cortez, Idolina; Santoyo, Gustavo; Hernández-Soberano, Christian; Valencia-Cantero, Eduardo

    2013-12-01

    Plant diseases caused by fungal pathogens such as Botrytis cinerea and the oomycete Phytophthora cinnamomi affect agricultural production worldwide. Control of these pests can be done by the use of fungicides such as captan, which may have deleterious effects on human health. This study demonstrates that the rhizobacterium Arthrobacter agilis UMCV2 produces volatile organic compounds that inhibit the growth of B. cinerea in vitro. A single compound from the volatile blends, namely dimethylhexadecylamine (DMHDA), could inhibit the growth of both B. cinerea and P. cinnamomi when supplied to the growth medium in low concentrations. DMHDA also inhibited the growth of beneficial fungi Trichoderma virens and Trichoderma atroviride but at much higher concentrations. DMHDA-related aminolipids containing 4, 8, 10, 12, and 14 carbons in the alkyl chain were tested for their inhibitory effect on the growth of the pathogens. The results show that the most active compound from those tested was dimethyldodecylamine. This effect correlates with a decrease in the number of membrane lipids present in the mycelium of the pathogen including eicosanoic acid, (Z)-9-hexadecenoic acid, methyl ester, and (Z)-9-octadecenoic acid, methyl ester. Strawberry leaflets treated with DMHDA were not injured by the compound. These data indicate that DMHDA and related compounds, which can be produced by microorganisms may effectively inhibit the proliferation of certain plant pathogens. PMID:23674267

  3. The Rsm regulon of plant growth-promoting Pseudomonas fluorescens SS101: role of small RNAs in regulation of lipopeptide biosynthesis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The rhizobacterium Pseudomonas fluorescens SS101 inhibits growth of oomycete and fungal pathogens, and induces resistance in plants against pathogens and insects. To unravel regulatory pathways of secondary metabolite production in SS101, we conducted a genome-wide search for sRNAs and performed tra...

  4. Production of Indole-3-Acetic Acid via the Indole-3-Acetamide Pathway in the Plant-Beneficial Bacterium Pseudomonas chlororaphis O6 Is Inhibited by ZnO Nanoparticles but Enhanced by CuO Nanoparticles

    PubMed Central

    Zeng, Jia; McLean, Joan E.; Britt, David W.; Zhan, Jixun; Anderson, Anne J.

    2012-01-01

    The beneficial bacterium Pseudomonas chlororaphis O6 produces indole-3-acetic acid (IAA), a plant growth regulator. However, the pathway involved in IAA production in this bacterium has not been reported. In this paper we describe the involvement of the indole-3-acetamide (IAM) pathway in IAA production in P. chlororaphis O6 and the effects of CuO and ZnO nanoparticles (NPs). Sublethal levels of CuO and ZnO NPs differentially affected the levels of IAA secreted in medium containing tryptophan as the precursor. After 15 h of growth, CuO NP-exposed cells had metabolized more tryptophan than the control and ZnO NP-challenged cells. The CuO NP-treated cells produced higher IAA levels than control cultures lacking NPs. In contrast, ZnO NPs inhibited IAA production. Mixing of CuO and ZnO NPs resulted in an intermediate level of IAA production relative to the levels in the separate CuO and ZnO NP treatments. The effect of CuO NPs on IAA levels could be duplicated by ions at the concentrations released from the NPs. However, ion release did not account for the inhibition caused by the ZnO NPs. The mechanism underlying changes in IAA levels cannot be accounted for by effects on transcript accumulation from genes encoding a tryptophan permease or the IAM hydrolase in 15-h cultures. These findings raise the issue of whether sublethal doses of NPs would modify the beneficial effects of association between plants and bacteria. PMID:22210218

  5. Characterization of the SPI-1 and Rsp type three secretion systems in Pseudomonas fluorescens F113.

    PubMed

    Barret, Matthieu; Egan, Frank; Moynihan, Jennifer; Morrissey, John P; Lesouhaitier, Olivier; O'Gara, Fergal

    2013-06-01

    Pseudomonas fluorescens F113 is a plant growth-promoting rhizobacterium (PGPR) isolated from the sugar beet rhizosphere. The recent annotation of the F113 genome sequence has revealed that this strain encodes a wide array of secretion systems, including two complete type three secretion systems (T3SSs) belonging to the Hrp1 and SPI-1 families. While Hrp1 T3SSs are frequently encoded in other P. fluorescens strains, the presence of a SPI-1 T3SS in a plant-beneficial bacterial strain was unexpected. In this work, the genetic organization and expression of these two T3SS loci have been analysed by a combination of transcriptional reporter fusions and transcriptome analyses. Overexpression of two transcriptional activators has shown a number of genes encoding putative T3 effectors. In addition, the influence of these two T3SSs during the interaction of P. fluorescens F113 with some bacterial predators was also assessed. Our data revealed that the transcriptional activator hilA is induced by amoeba and that the SPI-1 T3SS could potentially be involved in resistance to amoeboid grazing.

  6. Effects of a rhizobacterium on the growth of and chromium remediation by Lemna minor.

    PubMed

    Tang, Jie; Zhang, Ying; Cui, Yan; Ma, Jiong

    2015-07-01

    Duckweed has shown great potential for both energy and environmental applications, particularly in wastewater treatment and fuel ethanol production. A rhizobacterium, Exiguobacterium sp. MH3, has been reported to associate with the duckweed Lemna minor for symbiotic growth. The aim of this work is to study the effects of rhizobacterium MH3 on L. minor growth and chromium (Cr) remediation. It appeared to have a synergism between the rhizobacterium MH3 and duckweed; the presence of strain MH3 promoted the growth of duckweeds by increasing both the frond number and dry weight of duckweed by more than 30%, while duckweed in turn provided essential carbon source and energy for the growth of rhizobacterium MH3. Under Cr(VI) exposure, particularly at higher Cr(VI) concentrations, Exiguobacterium sp. MH3 significantly alleviated the harmful effects of the stress on the duckweed by promoting duckweed growth and preventing duckweed from excessive uptake of Cr. Potential mechanisms were also discussed in light of the genome sequence of strain MH3, and it was speculated that siderophores and indole-3-acetic acid (IAA) secreted by strain MH3 might contribute to promoting duckweed growth.

  7. Genome Sequence of the Banana Plant Growth-Promoting Rhizobacterium Bacillus amyloliquefaciens BS006

    PubMed Central

    Gamez, Rocío M.; Rodríguez, Fernando; Bernal, Johan F.; Agarwala, Richa; Landsman, David

    2015-01-01

    Bacillus amyloliquefaciens is an important plant growth-promoting rhizobacterium (PGPR). We report the first whole-genome sequence of PGPR Bacillus amyloliquefaciens evaluated in Colombian banana plants. The genome sequences encode genes involved in plant growth and defense, including bacteriocins, ribosomally synthesized antibacterial peptides, in addition to genes that provide resistance to toxic compounds. PMID:26607897

  8. Effects of a rhizobacterium on the growth of and chromium remediation by Lemna minor.

    PubMed

    Tang, Jie; Zhang, Ying; Cui, Yan; Ma, Jiong

    2015-07-01

    Duckweed has shown great potential for both energy and environmental applications, particularly in wastewater treatment and fuel ethanol production. A rhizobacterium, Exiguobacterium sp. MH3, has been reported to associate with the duckweed Lemna minor for symbiotic growth. The aim of this work is to study the effects of rhizobacterium MH3 on L. minor growth and chromium (Cr) remediation. It appeared to have a synergism between the rhizobacterium MH3 and duckweed; the presence of strain MH3 promoted the growth of duckweeds by increasing both the frond number and dry weight of duckweed by more than 30%, while duckweed in turn provided essential carbon source and energy for the growth of rhizobacterium MH3. Under Cr(VI) exposure, particularly at higher Cr(VI) concentrations, Exiguobacterium sp. MH3 significantly alleviated the harmful effects of the stress on the duckweed by promoting duckweed growth and preventing duckweed from excessive uptake of Cr. Potential mechanisms were also discussed in light of the genome sequence of strain MH3, and it was speculated that siderophores and indole-3-acetic acid (IAA) secreted by strain MH3 might contribute to promoting duckweed growth. PMID:25631740

  9. Genome Analysis of Bacillus amyloliquefaciens Subsp. plantarum UCMB5113: A Rhizobacterium That Improves Plant Growth and Stress Management

    PubMed Central

    Niazi, Adnan; Manzoor, Shahid; Asari, Shashidar; Bejai, Sarosh; Meijer, Johan; Bongcam-Rudloff, Erik

    2014-01-01

    The Bacillus amyloliquefaciens subsp. plantarum strain UCMB5113 is a Gram-positive rhizobacterium that can colonize plant roots and stimulate plant growth and defense based on unknown mechanisms. This reinforcement of plants may provide protection to various forms of biotic and abiotic stress. To determine the genetic traits involved in the mechanism of plant-bacteria association, the genome sequence of UCMB5113 was obtained by assembling paired-end Illumina reads. The assembled chromosome of 3,889,532 bp was predicted to encode 3,656 proteins. Genes that potentially contribute to plant growth promotion such as indole-3-acetic acid (IAA) biosynthesis, acetoin synthesis and siderophore production were identified. Moreover, annotation identified putative genes responsible for non-ribosomal synthesis of secondary metabolites and genes supporting environment fitness of UCMB5113 including drug and metal resistance. A large number of genes encoding a diverse set of secretory proteins, enzymes of primary and secondary metabolism and carbohydrate active enzymes were found which reflect a high capacity to degrade various rhizosphere macromolecules. Additionally, many predicted membrane transporters provides the bacterium with efficient uptake capabilities of several nutrients. Although, UCMB5113 has the possibility to produce antibiotics and biosurfactants, the protective effect of plants to pathogens seems to be indirect and due to priming of plant induced systemic resistance. The availability of the genome enables identification of genes and their function underpinning beneficial interactions of UCMB5113 with plants. PMID:25119988

  10. Application of Pseudomonas fluorescens to Blackberry under Field Conditions Improves Fruit Quality by Modifying Flavonoid Metabolism.

    PubMed

    Garcia-Seco, Daniel; Zhang, Yang; Gutierrez-Mañero, Francisco J; Martin, Cathie; Ramos-Solano, Beatriz

    2015-01-01

    Application of a plant growth promoting rhizobacterium (PGPR), Pseudomonas fluorescens N21.4, to roots of blackberries (Rubus sp.) is part of an optimised cultivation practice to improve yields and quality of fruit throughout the year in this important fruit crop. Blackberries are especially rich in flavonoids and therefore offer potential benefits for human health in prevention or amelioration of chronic diseases. However, the phenylpropanoid pathway and its regulation during ripening have not been studied in detail, in this species. PGPR may trigger flavonoid biosynthesis as part of an induced systemic response (ISR) given the important role of this pathway in plant defence, to cause increased levels of flavonoids in the fruit. We have identified structural genes encoding enzymes of the phenylpropanoid and flavonoid biosynthetic pathways catalysing the conversion of phenylalanine to the final products including flavonols, anthocyanins and catechins from blackberry, and regulatory genes likely involved in controlling the activity of pathway branches. We have also measured the major flavonols, anthocyanins and catechins at three stages during ripening. Our results demonstrate the coordinated expression of flavonoid biosynthetic genes with the accumulation of anthocyanins, catechins, and flavonols in developing fruits of blackberry. Elicitation of blackberry plants by treatment of roots with P.fluorescens N21.4, caused increased expression of some flavonoid biosynthetic genes and an accompanying increase in the concentration of selected flavonoids in fruits. Our data demonstrate the physiological mechanisms involved in the improvement of fruit quality by PGPR under field conditions, and highlight some of the genetic targets of elicitation by beneficial bacteria. PMID:26559418

  11. Application of Pseudomonas fluorescens to Blackberry under Field Conditions Improves Fruit Quality by Modifying Flavonoid Metabolism

    PubMed Central

    Garcia-Seco, Daniel; Zhang, Yang; Gutierrez-Mañero, Francisco J.; Martin, Cathie; Ramos-Solano, Beatriz

    2015-01-01

    Application of a plant growth promoting rhizobacterium (PGPR), Pseudomonas fluorescens N21.4, to roots of blackberries (Rubus sp.) is part of an optimised cultivation practice to improve yields and quality of fruit throughout the year in this important fruit crop. Blackberries are especially rich in flavonoids and therefore offer potential benefits for human health in prevention or amelioration of chronic diseases. However, the phenylpropanoid pathway and its regulation during ripening have not been studied in detail, in this species. PGPR may trigger flavonoid biosynthesis as part of an induced systemic response (ISR) given the important role of this pathway in plant defence, to cause increased levels of flavonoids in the fruit. We have identified structural genes encoding enzymes of the phenylpropanoid and flavonoid biosynthetic pathways catalysing the conversion of phenylalanine to the final products including flavonols, anthocyanins and catechins from blackberry, and regulatory genes likely involved in controlling the activity of pathway branches. We have also measured the major flavonols, anthocyanins and catechins at three stages during ripening. Our results demonstrate the coordinated expression of flavonoid biosynthetic genes with the accumulation of anthocyanins, catechins, and flavonols in developing fruits of blackberry. Elicitation of blackberry plants by treatment of roots with P.fluorescens N21.4, caused increased expression of some flavonoid biosynthetic genes and an accompanying increase in the concentration of selected flavonoids in fruits. Our data demonstrate the physiological mechanisms involved in the improvement of fruit quality by PGPR under field conditions, and highlight some of the genetic targets of elicitation by beneficial bacteria. PMID:26559418

  12. Complete genome sequence of Paenibacillus riograndensis SBR5(T), a Gram-positive diazotrophic rhizobacterium.

    PubMed

    Brito, Luciana Fernandes; Bach, Evelise; Kalinowski, Jörn; Rückert, Christian; Wibberg, Daniel; Passaglia, Luciane M; Wendisch, Volker F

    2015-08-10

    Paenibacillus riograndensis is a Gram-positive rhizobacterium which exhibits plant growth promoting activities. It was isolated from the rhizosphere of wheat grown in the state of Rio Grande do Sul, Brazil. Here we announce the complete genome sequence of P. riograndensis strain SBR5(T). The genome of P. riograndensis SBR5(T) consists of a circular chromosome of 7,893,056bps. The genome was finished and fully annotated, containing 6705 protein coding genes, 87 tRNAs and 27 rRNAs. The knowledge of the complete genome helped to explain why P. riograndensis SBR5(T) can grow with the carbon sources arabinose and mannitol, but not myo-inositol, and to explain physiological features such as biotin auxotrophy and antibiotic resistances. The genome sequence will be valuable for functional genomics and ecological studies as well as for application of P. riograndensis SBR5(T) as plant growth-promoting rhizobacterium.

  13. dRNA-Seq Reveals Genomewide TSSs and Noncoding RNAs of Plant Beneficial Rhizobacterium Bacillus amyloliquefaciens FZB42

    PubMed Central

    Fan, Ben; Förstner, Konrad; Vogel, Jörg; Borriss, Rainer; Wu, Xiao-Qin

    2015-01-01

    Bacillus amyloliquefaciens subsp. plantarum FZB42 is a representative of Gram-positive plant-growth-promoting rhizobacteria (PGPR) that inhabit plant root environments. In order to better understand the molecular mechanisms of bacteria-plant symbiosis, we have systematically analyzed the primary transcriptome of strain FZB42 grown under rhizosphere-mimicking conditions using differential RNA sequencing (dRNA-seq). Our analysis revealed 4,877 transcription start sites for protein-coding genes, identified genes differentially expressed under different growth conditions, and corrected many previously mis-annotated genes. We also identified a large number of riboswitches and cis-encoded antisense RNAs, as well as trans-encoded small noncoding RNAs that may play important roles in the gene regulation of Bacillus. Overall, our analyses provided a landscape of Bacillus primary transcriptome and improved the knowledge of rhizobacteria-host interactions. PMID:26540162

  14. [Chemical composition and immunochemical characteristics of the lipopolysaccharide of nitrogen-fixing rhizobacterium Azospirillum brasilense CD].

    PubMed

    Konnova, O N; Burygin, G L; Fedonenko, Iu P; Matora, L Iu; Pankin, K E; Konnova, S A; Ignatov, V V

    2006-01-01

    The chemical composition of the lipopolysaccharide of the associative diazotrophic rhizobacterium Azospirillum brasilense Cd has been studied. Among the main components of the hydrophobic part of the lipopolysaccharide, we identified 3-hydroxytetradecanoic, hexadecenoic, 3-hydroxyhexadecanoic, hexadecanoic, octadecenoic, and nanodecanoic fatty acids; the carbohydrate part contained rhamnose, galactose, and mannose. Polyclonal antibodies against the preparation under study were raised in rabbits. Serological relations between A. brasilense Cd and other strains of Azospirillum spp. were studied using double radial immunodiffusion and enzyme-linked immunosorbent assay.

  15. A novel interaction between plant-beneficial rhizobacteria and roots: colonization induces corn resistance against the root herbivore Diabrotica speciosa.

    PubMed

    Santos, Franciele; Peñaflor, Maria Fernanda G V; Paré, Paul W; Sanches, Patrícia A; Kamiya, Aline C; Tonelli, Mateus; Nardi, Cristiane; Bento, José Mauricio S

    2014-01-01

    A number of soil-borne microorganisms, such as mycorrhizal fungi and rhizobacteria, establish mutualistic interactions with plants, which can indirectly affect other organisms. Knowledge of the plant-mediated effects of mutualistic microorganisms is limited to aboveground insects, whereas there is little understanding of what role beneficial soil bacteria may play in plant defense against root herbivory. Here, we establish that colonization by the beneficial rhizobacterium Azospirillum brasilense affects the host selection and performance of the insect Diabrotica speciosa. Root larvae preferentially orient toward the roots of non-inoculated plants versus inoculated roots and gain less weight when feeding on inoculated plants. As inoculation by A. brasilense induces higher emissions of (E)-β-caryophyllene compared with non-inoculated plants, it is plausible that the non-preference of D. speciosa for inoculated plants is related to this sesquiterpene, which is well known to mediate belowground insect-plant interactions. To the best of our knowledge, this is the first study showing that a beneficial rhizobacterium inoculant indirectly alters belowground plant-insect interactions. The role of A. brasilense as part of an integrative pest management (IPM) program for the protection of corn against the South American corn rootworm, D. speciosa, is considered.

  16. Complete Genome Sequence of Bacillus amyloliquefaciens Strain Co1-6, a Plant Growth-Promoting Rhizobacterium of Calendula officinalis.

    PubMed

    Köberl, Martina; White, Richard A; Erschen, Sabine; Spanberger, Nora; El-Arabi, Tarek F; Jansson, Janet K; Berg, Gabriele

    2015-01-01

    The genome sequence of Bacillus amyloliquefaciens strain Co1-6, a plant growth-promoting rhizobacterium (PGPR) with broad-spectrum antagonistic activity against plant-pathogenic fungi, bacteria, and nematodes, consists of a single 3.9-Mb circular chromosome. The genome reveals genes putatively responsible for its promising biocontrol and PGP properties. PMID:26272562

  17. Genome Sequence of Rhizobacterium Serratia marcescens Strain 90-166, Which Triggers Induced Systemic Resistance and Plant Growth Promotion

    PubMed Central

    Kloepper, Joseph W.

    2015-01-01

    The rhizobacterium Serratia marcescens strain 90-166 elicits induced systemic resistance against plant pathogens and herbivores and promotes plant growth under greenhouse and field conditions. Strain 90-166 secretes volatile compounds, siderophores, salicylic acid, and quorum-sensing autoinducers as bacterial determinants toward plant health. Herein, we present its draft genome sequence. PMID:26089427

  18. Complete genome sequence of Bacillus amyloliquefaciens strain Co1-6, a plant growth-promoting rhizobacterium of Calendula officinalis

    DOE PAGES

    Köberl, Martina; White, Richard A.; Erschen, Sabine; Spanberger, Nora; El-Arabi, Tarek F.; Jansson, Janet K.; Berg, Gabriele

    2015-08-13

    The genome sequence of Bacillus amyloliquefaciens strain Co1-6, a plant growth-promoting rhizobacterium (PGPR) with broad-spectrum antagonistic activity against plant-pathogenic fungi, bacteria, and nematodes, consists of a single 3.9-Mb circular chromosome. The genome reveals genes putatively responsible for its promising biocontrol and PGP properties.

  19. Complete genome sequence of Bacillus amyloliquefaciens strain Co1-6, a plant growth-promoting rhizobacterium of Calendula officinalis

    SciTech Connect

    Koeberl, Martina; White, Richard A.; Erschen, Sabine; Spanberger, Nora; El-Arabi, Tarek F.; Jansson, Janet K.; Berg, Gabriele

    2015-08-13

    The genome sequence of Bacillus amyloliquefaciens strain Co1-6, a plant growth-promoting rhizobacterium (PGPR) with broad-spectrum antagonistic activities against plant pathogenic fungi, bacteria and nematodes, consists of a single 3.9 Mb circular chromosome. The genome reveals genes putatively responsible for its promising biocontrol and PGP properties.

  20. Complete Genome Sequence of Bacillus amyloliquefaciens Strain Co1-6, a Plant Growth-Promoting Rhizobacterium of Calendula officinalis.

    PubMed

    Köberl, Martina; White, Richard A; Erschen, Sabine; Spanberger, Nora; El-Arabi, Tarek F; Jansson, Janet K; Berg, Gabriele

    2015-01-01

    The genome sequence of Bacillus amyloliquefaciens strain Co1-6, a plant growth-promoting rhizobacterium (PGPR) with broad-spectrum antagonistic activity against plant-pathogenic fungi, bacteria, and nematodes, consists of a single 3.9-Mb circular chromosome. The genome reveals genes putatively responsible for its promising biocontrol and PGP properties.

  1. Draft Genome Sequence of a Biocontrol Rhizobacterium, Chryseobacterium kwangjuense Strain KJ1R5, Isolated from Pepper (Capsicum annuum)

    PubMed Central

    Jeong, Jin-Ju; Park, Hongjae; Park, Byeong Hyeok; Mannaa, Mohamed; Sang, Mee Kyung

    2016-01-01

    Strain KJ1R5 of the rhizobacterium Chryseobacterium kwangjuense is an effective biocontrol agent against Phytophthora blight of pepper caused by a destructive soilborne oomycete, Phytophthora capsici. Here, we present the draft genome sequence of strain KJ1R5, which contains genes related to biocontrol, plant growth promotion, and environmental stress adaptation. PMID:27103726

  2. Genome Sequence of Rhizobacterium Serratia marcescens Strain 90-166, Which Triggers Induced Systemic Resistance and Plant Growth Promotion.

    PubMed

    Jeong, Haeyoung; Kloepper, Joseph W; Ryu, Choong-Min

    2015-06-18

    The rhizobacterium Serratia marcescens strain 90-166 elicits induced systemic resistance against plant pathogens and herbivores and promotes plant growth under greenhouse and field conditions. Strain 90-166 secretes volatile compounds, siderophores, salicylic acid, and quorum-sensing autoinducers as bacterial determinants toward plant health. Herein, we present its draft genome sequence.

  3. The Beneficiation of Education

    ERIC Educational Resources Information Center

    Senger, April J.

    2014-01-01

    When the challenge of adapting curriculum to meet the requirements of the Common Core State Standards were presented, this author immediately sought out the assistance of experts in another field: the school library staff. It was apparent that staff needed to practice the beneficiation of the current curriculum to meet the CCSS requirements.…

  4. Biodegradation of the neonicotinoid insecticide thiamethoxam by the nitrogen-fixing and plant-growth-promoting rhizobacterium Ensifer adhaerens strain TMX-23.

    PubMed

    Zhou, Guang-Can; Wang, Ying; Zhai, Shan; Ge, Feng; Liu, Zhong-Hua; Dai, Yi-Jun; Yuan, Sheng; Hou, Jun-Yi

    2013-05-01

    Thiamethoxam (THIA), a second generation neonicotinoid insecticide in the thianicotinyl subclass, is used worldwide. Environmental studies revealed that microbial degradation is the major mode of removal of this pesticide from soil. However, microbial transformation of THIA is poorly understood. In the present study, we isolated a bacterium able to degrade THIA from rhizosphere soil. The bacterium was identified as Ensifer adhaerens by its morphology and 16S ribosomal DNA sequence analysis. High-performance liquid chromatography and mass spectrometry analysis suggested that the major metabolic pathway of THIA in E. adhaerens TMX-23 involves the transformation of its N-nitroimino group (=N-NO2) to N-nitrosoimino (=N-NO) and urea (=O) metabolites. E. adhaerens TMX-23 is a nitrogen-fixing bacterium harboring two types of nifH genes in its genome, one of which is 98 % identical to the nifH gene in the cyanobacterium Calothrix sp. MCC-3A. E. adhaerens TMX-23 released various plant-growth-promoting substances including indole-3-acetic acid, exopolysaccharides, ammonia, HCN, and siderophores. Inoculation of E. adhaerens TMX-23 onto soybean seeds (Glycine max L.) with NaCl at 50, 100, or 154 mmol/L increased the seed germination rate by 14, 21, and 30 %, respectively. THIA at 10 mg/L had beneficial effects on E. adhaerens TMX-23, enhancing growth of the bacterium and its production of salicylic acid, an important plant phytohormone associated with plant defense responses against abiotic stress. The nitrogen-fixing and plant-growth-promoting rhizobacterium E. adhaerens TMX-23, which is able to degrade THIA, has the potential for bioaugmentation as well as to promote growth of field crops in THIA-contaminated soil.

  5. Pseudomonas chemotaxis.

    PubMed

    Sampedro, Inmaculada; Parales, Rebecca E; Krell, Tino; Hill, Jane E

    2015-01-01

    Pseudomonads sense changes in the concentration of chemicals in their environment and exhibit a behavioral response mediated by flagella or pili coupled with a chemosensory system. The two known chemotaxis pathways, a flagella-mediated pathway and a putative pili-mediated system, are described in this review. Pseudomonas shows chemotaxis response toward a wide range of chemicals, and this review includes a summary of them organized by chemical structure. The assays used to measure positive and negative chemotaxis swimming and twitching Pseudomonas as well as improvements to those assays and new assays are also described. This review demonstrates that there is ample research and intellectual space for future investigators to elucidate the role of chemotaxis in important processes such as pathogenesis, bioremediation, and the bioprotection of plants and animals.

  6. Modulation of Quorum Sensing in Acylhomoserine Lactone-Producing or -Degrading Tobacco Plants Leads to Alteration of Induced Systemic Resistance Elicited by the Rhizobacterium Serratia marcescens 90-166

    PubMed Central

    Ryu, Choong-Min; Choi, Hye Kyung; Lee, Chi-Ho; Murphy, John F.; Lee, Jung-Kee; Kloepper, Joseph W.

    2013-01-01

    Numerous root-associated bacteria (rhizobacteria) are known to elicit induced systemic resistance (ISR) in plants. Bacterial cell-density-dependent quorum sensing (QS) is thought to be important for ISR. Here, we investigated the role of QS in the ISR elicited by the rhizobacterium, Serratia marcescens strain 90–166, in tobacco. Since S. marcescens 90–166 produces at least three QS signals, QS-mediated ISR in strain 90–166 has been difficult to understand. Therefore, we investigated the ISR capacity of two transgenic tobacco (Nicotiana tabacum) plants that contained either bacterial acylhomoserine lactone-producing (AHL) or -degrading (AiiA) genes in conjunction with S. marcescens 90–166 to induce resistance against bacterial and viral pathogens. Root application of S. marcescens 90–166 increased ISR to the bacterial pathogens, Pectobacterium carotovorum subsp. carotovorum and Pseudomonas syringae pv. tabaci, in AHL plants and decreased ISR in AiiA plants. In contrast, ISR to Cucumber mosaic virus was reduced in AHL plants treated with S. marcescens 90–166 but enhanced in AiiA plants. Taken together, these data indicate that QS-dependent ISR is elicited by S. marcescens 90–166 in a pathogen-dependent manner. This study provides insight into QS-dependent ISR in tobacco elicited by S. marcescens 90–166. PMID:25288945

  7. Modulation of Quorum Sensing in Acylhomoserine Lactone-Producing or -Degrading Tobacco Plants Leads to Alteration of Induced Systemic Resistance Elicited by the Rhizobacterium Serratia marcescens 90-166.

    PubMed

    Ryu, Choong-Min; Choi, Hye Kyung; Lee, Chi-Ho; Murphy, John F; Lee, Jung-Kee; Kloepper, Joseph W

    2013-06-01

    Numerous root-associated bacteria (rhizobacteria) are known to elicit induced systemic resistance (ISR) in plants. Bacterial cell-density-dependent quorum sensing (QS) is thought to be important for ISR. Here, we investigated the role of QS in the ISR elicited by the rhizobacterium, Serratia marcescens strain 90-166, in tobacco. Since S. marcescens 90-166 produces at least three QS signals, QS-mediated ISR in strain 90-166 has been difficult to understand. Therefore, we investigated the ISR capacity of two transgenic tobacco (Nicotiana tabacum) plants that contained either bacterial acylhomoserine lactone-producing (AHL) or -degrading (AiiA) genes in conjunction with S. marcescens 90-166 to induce resistance against bacterial and viral pathogens. Root application of S. marcescens 90-166 increased ISR to the bacterial pathogens, Pectobacterium carotovorum subsp. carotovorum and Pseudomonas syringae pv. tabaci, in AHL plants and decreased ISR in AiiA plants. In contrast, ISR to Cucumber mosaic virus was reduced in AHL plants treated with S. marcescens 90-166 but enhanced in AiiA plants. Taken together, these data indicate that QS-dependent ISR is elicited by S. marcescens 90-166 in a pathogen-dependent manner. This study provides insight into QS-dependent ISR in tobacco elicited by S. marcescens 90-166.

  8. Process for beneficiating coal

    SciTech Connect

    Burgess, L.E.; Fox, K.M.; Herman, D.E.; McGarry, P.E.

    1982-06-01

    Mine run coal is pulverized and the extended surfaces of the coal particles are rendered hydrophobic and oilophilic by a chemical bonding and graft polymerization reaction with a water insoluble organic polymerizable monomer under peroxidation influence in a predominantly water reaction medium. The mineral ash present in the coal and particularly the iron pyrites remains hydrophilic and is separated from the polymeric organic surface bonded coal product in a water washing step wherein the washed coal floats on and is recovered from the water phase and the ash is removed with the separated wash water in a critical wash step. Excess water is removed from the beneficiated hydrophobic surface-altered coal product mechanically. The hydrophobic and oilophilic organic polymeric surface bonded coating about the coal particles is fortified by inclusion of additional unbound free fatty acids by further small additions thereof. The carboxylic acid groups present in the coal-oil product are thereafter converted to a metal soap. The beneficiated coal product can be used ''dry,'' or additional quantities of a liquid hydrocarbon fuel can be incorporated with the ''dry'' beneficiated coal product to produce a flowable fluid or liquid coal product having the rheological property of marked thixotropy. Introduction of this physically induced property into the liquid coal-oil-mixture prevents settling out of the heavier coal particles from the relatively ash-free fluid fuel composition under extended storage periods.

  9. Apparatus for beneficiating coal

    SciTech Connect

    Burgess, L.E.; Fox, K.M.; Herman, D.E.; McGarry, P.E.

    1985-08-20

    Mine run coal is pulverized and the extended surfaces of the coal particles are rendered hydrophobic and oilophilic by a chemical bonding and graft polymerization reaction with a water insoluble organic polymerizable monomer under peroxidation influence in a predominantly water reaction medium. The mineral ash present in the coal and particularly the iron pyrites remains hydrophilic and is separated from the polymeric organic surface bonded coal product in a water washing step wherein the washed coal floats on and is recovered from the water phase and the ash is removed with the separated wash water in a critical wash step. Excess water is removed from the beneficiated hydrophobic surface-altered coal product mechanically. The hydrophobic and oilophilic organic polymeric surface bonded coating about the coal particles is fortified by inclusion of additional unbound free fatty acids by further small additions thereof. The carboxylic acid groups present in the coal-oil product are thereafter converted to a metal soap. The beneficiated coal product can be used ''dry'', or additional quantities of a liquid hydrocarbon fuel can be incorporated with the ''dry'' beneficiated coal product to produce a flowable fluid or liquid coal product having the rheological property of marked thixotropy. Introduction of this physically induced property into the liquid coal-oil-mixture prevents settling out of the heavier coal particles from the relatively ash-free fluid fuel composition under extended storage periods.

  10. Biological Control of Apple Anthracnose by Paenibacillus polymyxa APEC128, an Antagonistic Rhizobacterium.

    PubMed

    Kim, Young Soo; Balaraju, Kotnala; Jeon, Yongho

    2016-06-01

    The present study investigated the suppression of the disease development of anthracnose caused by Colletotrichum gloeosporioides and C. acutatum in harvested apples using an antagonistic rhizobacterium Paenibacillus polymyxa APEC128 (APEC128). Out of 30 bacterial isolates from apple rhizosphere screened for antagonistic activity, the most effective strain was APEC128 as inferred from the size of the inhibition zone. This strain showed a greater growth in brain-heart infusion (BHI) broth compared to other growth media. There was a reduction in anthracnose symptoms caused by the two fungal pathogens in harvested apples after their treatment with APEC128 in comparison with non-treated control. This effect is explained by the increased production of protease and amylase by APEC128, which might have inhibited mycelial growth. In apples treated with different APEC128 suspensions, the disease caused by C. gloeosporioides and C. acutatum was greatly suppressed (by 83.6% and 79%, respectively) in treatments with the concentration of 1 × 10(8) colony forming units (cfu)/ml compared to other lower dosages, suggesting that the suppression of anthracnose development on harvested apples is dose-dependent. These results indicated that APEC128 is one of the promising agents in the biocontrol of apple anthracnose, which might help to increase the shelf-life of apple fruit during the post-harvest period. PMID:27298600

  11. Biological Control of Apple Anthracnose by Paenibacillus polymyxa APEC128, an Antagonistic Rhizobacterium

    PubMed Central

    Kim, Young Soo; Balaraju, Kotnala; Jeon, Yongho

    2016-01-01

    The present study investigated the suppression of the disease development of anthracnose caused by Colletotrichum gloeosporioides and C. acutatum in harvested apples using an antagonistic rhizobacterium Paenibacillus polymyxa APEC128 (APEC128). Out of 30 bacterial isolates from apple rhizosphere screened for antagonistic activity, the most effective strain was APEC128 as inferred from the size of the inhibition zone. This strain showed a greater growth in brain-heart infusion (BHI) broth compared to other growth media. There was a reduction in anthracnose symptoms caused by the two fungal pathogens in harvested apples after their treatment with APEC128 in comparison with non-treated control. This effect is explained by the increased production of protease and amylase by APEC128, which might have inhibited mycelial growth. In apples treated with different APEC128 suspensions, the disease caused by C. gloeosporioides and C. acutatum was greatly suppressed (by 83.6% and 79%, respectively) in treatments with the concentration of 1 × 108 colony forming units (cfu)/ml compared to other lower dosages, suggesting that the suppression of anthracnose development on harvested apples is dose-dependent. These results indicated that APEC128 is one of the promising agents in the biocontrol of apple anthracnose, which might help to increase the shelf-life of apple fruit during the post-harvest period. PMID:27298600

  12. Fever: is it beneficial?

    PubMed

    Blatteis, C M

    1986-01-01

    Data obtained in lizards infected with live bacteria suggest that fever may be beneficial to their survival. An adaptive value of fever has also been inferred in mammals, but the results are equivocal. Findings that certain leukocyte functions are enhanced in vitro at high temperatures have provided a possible explanation for the alleged benefits of fever. However, serious questions exist as to whether results from experiments in ectotherms and in vitro can properly be extrapolated to in vivo endothermic conditions. Indeed, various studies have yielded results inconsistent with the survival benefits attributed to fever, and fever is not an obligatory feature of all infections under all conditions. Certainly, the widespread use of antipyretics, without apparent adverse effects on the course of disease, argues against fever having great benefit to the host. In sum, although fever is a cardinal manifestation of infection, conclusive evidence that it has survival value in mammals is still lacking.

  13. Draft Genome Sequence of Bacillus cereus LCR12, a Plant Growth–Promoting Rhizobacterium Isolated from a Heavy Metal–Contaminated Environment

    PubMed Central

    Egidi, Eleonora; Wood, Jennifer L.; Mathews, Elizabeth; Fox, Edward; Liu, Wuxing

    2016-01-01

    Bacillus cereus LCR12 is a plant growth–promoting rhizobacterium, isolated from a heavy metal–contaminated environment. The 6.01-Mb annotated genome sequence provides the genetic basis for revealing its potential application to remediate contaminated soils in association with plants. PMID:27688340

  14. Draft Genome Sequence of Bacillus cereus LCR12, a Plant Growth-Promoting Rhizobacterium Isolated from a Heavy Metal-Contaminated Environment.

    PubMed

    Egidi, Eleonora; Wood, Jennifer L; Mathews, Elizabeth; Fox, Edward; Liu, Wuxing; Franks, Ashley E

    2016-01-01

    Bacillus cereus LCR12 is a plant growth-promoting rhizobacterium, isolated from a heavy metal-contaminated environment. The 6.01-Mb annotated genome sequence provides the genetic basis for revealing its potential application to remediate contaminated soils in association with plants. PMID:27688340

  15. Complete genome sequence of Bacillus amyloliquefaciens strain Co1-6, a plant growth-promoting rhizobacterium of Calendula officinalis

    SciTech Connect

    Köberl, Martina; White, Richard A.; Erschen, Sabine; Spanberger, Nora; El-Arabi, Tarek F.; Jansson, Janet K.; Berg, Gabriele

    2015-08-13

    The genome sequence of Bacillus amyloliquefaciens strain Co1-6, a plant growth-promoting rhizobacterium (PGPR) with broad-spectrum antagonistic activity against plant-pathogenic fungi, bacteria, and nematodes, consists of a single 3.9-Mb circular chromosome. The genome reveals genes putatively responsible for its promising biocontrol and PGP properties.

  16. Draft Genome Sequence of Bacillus cereus LCR12, a Plant Growth-Promoting Rhizobacterium Isolated from a Heavy Metal-Contaminated Environment.

    PubMed

    Egidi, Eleonora; Wood, Jennifer L; Mathews, Elizabeth; Fox, Edward; Liu, Wuxing; Franks, Ashley E

    2016-09-29

    Bacillus cereus LCR12 is a plant growth-promoting rhizobacterium, isolated from a heavy metal-contaminated environment. The 6.01-Mb annotated genome sequence provides the genetic basis for revealing its potential application to remediate contaminated soils in association with plants.

  17. Beneficial Properties of Probiotics

    PubMed Central

    Shi, Lye Huey; Balakrishnan, Kunasundari; Thiagarajah, Kokila; Mohd Ismail, Nor Ismaliza; Yin, Ooi Shao

    2016-01-01

    Probiotics are live microorganisms that can be found in fermented foods and cultured milk, and are widely used for the preparation of infant food. They are well-known as “health friendly bacteria”, which exhibit various health beneficial properties such as prevention of bowel diseases, improving the immune system, for lactose intolerance and intestinal microbial balance, exhibiting antihypercholesterolemic and antihypertensive effects, alleviation of postmenopausal disorders, and reducing traveller’s diarrhoea. Recent studies have also been focused on their uses in treating skin and oral diseases. In addition to that, modulation of the gut-brain by probiotics has been suggested as a novel therapeutic solution for anxiety and depression. Thus, this review discusses on the current probiotics-based products in Malaysia, criteria for selection of probiotics, and evidences obtained from past studies on how probiotics have been used in preventing intestinal disorders via improving the immune system, acting as an antihypercholesterolemic factor, improving oral and dermal health, and performing as anti-anxiety and anti-depressive agents.

  18. Beneficial bacteria inhibit cachexia

    PubMed Central

    Varian, Bernard J.; Goureshetti, Sravya; Poutahidis, Theofilos; Lakritz, Jessica R.; Levkovich, Tatiana; Kwok, Caitlin; Teliousis, Konstantinos; Ibrahim, Yassin M.; Mirabal, Sheyla; Erdman, Susan E.

    2016-01-01

    Muscle wasting, known as cachexia, is a debilitating condition associated with chronic inflammation such as during cancer. Beneficial microbes have been shown to optimize systemic inflammatory tone during good health; however, interactions between microbes and host immunity in the context of cachexia are incompletely understood. Here we use mouse models to test roles for bacteria in muscle wasting syndromes. We find that feeding of a human commensal microbe, Lactobacillus reuteri, to mice is sufficient to lower systemic indices of inflammation and inhibit cachexia. Further, the microbial muscle-building phenomenon extends to normal aging as wild type animals exhibited increased growth hormone levels and up-regulation of transcription factor Forkhead Box N1 [FoxN1] associated with thymus gland retention and longevity. Interestingly, mice with a defective FoxN1 gene (athymic nude) fail to inhibit sarcopenia after L. reuteri therapy, indicating a FoxN1-mediated mechanism. In conclusion, symbiotic bacteria may serve to stimulate FoxN1 and thymic functions that regulate inflammation, offering possible alternatives for cachexia prevention and novel insights into roles for microbiota in mammalian ontogeny and phylogeny. PMID:26933816

  19. Beneficial bacteria inhibit cachexia.

    PubMed

    Varian, Bernard J; Goureshetti, Sravya; Poutahidis, Theofilos; Lakritz, Jessica R; Levkovich, Tatiana; Kwok, Caitlin; Teliousis, Konstantinos; Ibrahim, Yassin M; Mirabal, Sheyla; Erdman, Susan E

    2016-03-15

    Muscle wasting, known as cachexia, is a debilitating condition associated with chronic inflammation such as during cancer. Beneficial microbes have been shown to optimize systemic inflammatory tone during good health; however, interactions between microbes and host immunity in the context of cachexia are incompletely understood. Here we use mouse models to test roles for bacteria in muscle wasting syndromes. We find that feeding of a human commensal microbe, Lactobacillus reuteri, to mice is sufficient to lower systemic indices of inflammation and inhibit cachexia. Further, the microbial muscle-building phenomenon extends to normal aging as wild type animals exhibited increased growth hormone levels and up-regulation of transcription factor Forkhead Box N1 [FoxN1] associated with thymus gland retention and longevity. Interestingly, mice with a defective FoxN1 gene (athymic nude) fail to inhibit sarcopenia after L. reuteri therapy, indicating a FoxN1-mediated mechanism. In conclusion, symbiotic bacteria may serve to stimulate FoxN1 and thymic functions that regulate inflammation, offering possible alternatives for cachexia prevention and novel insights into roles for microbiota in mammalian ontogeny and phylogeny. PMID:26933816

  20. Beneficial Properties of Probiotics

    PubMed Central

    Shi, Lye Huey; Balakrishnan, Kunasundari; Thiagarajah, Kokila; Mohd Ismail, Nor Ismaliza; Yin, Ooi Shao

    2016-01-01

    Probiotics are live microorganisms that can be found in fermented foods and cultured milk, and are widely used for the preparation of infant food. They are well-known as “health friendly bacteria”, which exhibit various health beneficial properties such as prevention of bowel diseases, improving the immune system, for lactose intolerance and intestinal microbial balance, exhibiting antihypercholesterolemic and antihypertensive effects, alleviation of postmenopausal disorders, and reducing traveller’s diarrhoea. Recent studies have also been focused on their uses in treating skin and oral diseases. In addition to that, modulation of the gut-brain by probiotics has been suggested as a novel therapeutic solution for anxiety and depression. Thus, this review discusses on the current probiotics-based products in Malaysia, criteria for selection of probiotics, and evidences obtained from past studies on how probiotics have been used in preventing intestinal disorders via improving the immune system, acting as an antihypercholesterolemic factor, improving oral and dermal health, and performing as anti-anxiety and anti-depressive agents. PMID:27688852

  1. Beneficial Properties of Probiotics.

    PubMed

    Shi, Lye Huey; Balakrishnan, Kunasundari; Thiagarajah, Kokila; Mohd Ismail, Nor Ismaliza; Yin, Ooi Shao

    2016-08-01

    Probiotics are live microorganisms that can be found in fermented foods and cultured milk, and are widely used for the preparation of infant food. They are well-known as "health friendly bacteria", which exhibit various health beneficial properties such as prevention of bowel diseases, improving the immune system, for lactose intolerance and intestinal microbial balance, exhibiting antihypercholesterolemic and antihypertensive effects, alleviation of postmenopausal disorders, and reducing traveller's diarrhoea. Recent studies have also been focused on their uses in treating skin and oral diseases. In addition to that, modulation of the gut-brain by probiotics has been suggested as a novel therapeutic solution for anxiety and depression. Thus, this review discusses on the current probiotics-based products in Malaysia, criteria for selection of probiotics, and evidences obtained from past studies on how probiotics have been used in preventing intestinal disorders via improving the immune system, acting as an antihypercholesterolemic factor, improving oral and dermal health, and performing as anti-anxiety and anti-depressive agents. PMID:27688852

  2. Beneficial uses of radiation

    SciTech Connect

    Fox, M.R.

    1991-10-01

    An overall decline in technical literacy within the American public has come at a time when technological advances are accelerating in the United States and around the world. This had led to a large communication gulf between the general public and the technologists. Nowhere is this more evident then with the topic of radiation. Regrettably, too few people know about sources of radiation, the pervasiveness, amounts, and variabilities, and do not have a true understanding of the environment in which we live. Nor do many people know that radiation has been used in beneficial ways for decades around the world. While the general public does not know of the scientific applications to which radiation has been deployed, it nevertheless had benefited tremendously from these efforts. Thanks to the well know properties of radiation, scientific ingenuity has found many uses of radiation in chemical and agricultural research, biomedical research, in the diagnoses and treatment of hundreds of types of diseases, in industrial applications, food irradiation, and many others. This paper provides a sample of the types of uses to which radiation has been used to help advance the betterment of humankind.

  3. Beneficial Properties of Probiotics.

    PubMed

    Shi, Lye Huey; Balakrishnan, Kunasundari; Thiagarajah, Kokila; Mohd Ismail, Nor Ismaliza; Yin, Ooi Shao

    2016-08-01

    Probiotics are live microorganisms that can be found in fermented foods and cultured milk, and are widely used for the preparation of infant food. They are well-known as "health friendly bacteria", which exhibit various health beneficial properties such as prevention of bowel diseases, improving the immune system, for lactose intolerance and intestinal microbial balance, exhibiting antihypercholesterolemic and antihypertensive effects, alleviation of postmenopausal disorders, and reducing traveller's diarrhoea. Recent studies have also been focused on their uses in treating skin and oral diseases. In addition to that, modulation of the gut-brain by probiotics has been suggested as a novel therapeutic solution for anxiety and depression. Thus, this review discusses on the current probiotics-based products in Malaysia, criteria for selection of probiotics, and evidences obtained from past studies on how probiotics have been used in preventing intestinal disorders via improving the immune system, acting as an antihypercholesterolemic factor, improving oral and dermal health, and performing as anti-anxiety and anti-depressive agents.

  4. Pseudomonas 2007 Meeting Review

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pseudomonas is an important genus of bacteria. Pseudomonas aeruginosa is the third most common nosocomial pathogen in our society, associated with chronic and eventually fatal lung disease in cystic fibrosis patients, while Pseudomonas syringae species are prominent plant pathogens. The fluorescen...

  5. Mössbauer spectroscopic study of 57Fe metabolic transformations in the rhizobacterium Azospirillum brasilense Sp245

    NASA Astrophysics Data System (ADS)

    Kamnev, Alexander A.; Tugarova, Anna V.; Kovács, Krisztina; Biró, Borbála; Homonnay, Zoltán; Kuzmann, Ernő

    2014-04-01

    Preliminary 57Fe transmission Mössbauer spectroscopic data were obtained for the first time for live cells of the plant-growth-promoting rhizobacterium Azospirillum brasilense (wild-type strain Sp245) grown aerobically with 57FeIII-nitrilotriacetate (NTA) complex as a sole source of iron. The results obtained have shown that live cells actively reduce part of the assimilated iron(III) to iron(II), the latter amounting up to 33 % of total cellular iron after 18 h of growth, and 48 % after additional 3 days of storage of the dense wet cell suspension in nutrient-free saline solution in air at room temperature (measured at 80 K). The cellular iron(II) was found to be represented by two quadrupole doublets of different high-spin forms, while the parameters of the cellular iron(III) were close to those typical for bacterioferritins.

  6. Iron-regulated metabolites produced by Pseudomonas fluorescens WCS374r are not required for eliciting induced systemic resistance against Pseudomonas syringae pv. tomato in Arabidopsis

    PubMed Central

    Djavaheri, Mohammad; Mercado-Blanco, Jesús; Versluis, C; Meyer, J-M; Loon, L C; Bakker, Peter A H M

    2012-01-01

    The plant growth-promoting rhizobacterium Pseudomonas fluorescens WCS374r produces several iron-regulated metabolites, including the fluorescent siderophore pseudobactin (Psb374), salicylic acid (SA), and pseudomonine (Psm), a siderophore that contains a SA moiety. After purification of Psb374 from culture supernatant of WCS374r, its structure was determined following isoelectrofocusing and tandem mass spectrometry, and found to be identical to the fluorescent siderophore produced by P. fluorescens ATCC 13525. To study the role of SA and Psm production in colonization of Arabidopsis thaliana roots and in induced systemic resistance (ISR) against Pseudomonas syringae pv. tomato (Pst) by strain WCS374r, mutants disrupted in the production of these metabolites were obtained by homologous recombination. These mutants were further subjected to transposon Tn5 mutagenesis to generate mutants also deficient in Psb374 production. The mutants behaved similar to the wild type in both their Arabidopsis rhizosphere-colonizing capacity and their ability to elicit ISR against Pst. We conclude that Psb374, SA, and Psm production by P. fluorescens WCS374r are not required for eliciting ISR in Arabidopsis. PMID:23170230

  7. Augmenting iron accumulation in cassava by the beneficial soil bacterium Bacillus subtilis (GBO3).

    PubMed

    Freitas, Mônica A; Medeiros, Flavio H V; Carvalho, Samuel P; Guilherme, Luiz R G; Teixeira, William D; Zhang, Huiming; Paré, Paul W

    2015-01-01

    Cassava (Manihot esculenta), a major staple food in the developing world, provides a basic carbohydrate diet for over half a billion people living in the tropics. Despite the iron abundance in most soils, cassava provides insufficient iron for humans as the edible roots contain 3-12 times less iron than other traditional food crops such as wheat, maize, and rice. With the recent identification that the beneficial soil bacterium Bacillus subtilis (strain GB03) activates iron acquisition machinery to increase metal ion assimilation in Arabidopsis, the question arises as to whether this plant-growth promoting rhizobacterium also augments iron assimilation to increase endogenous iron levels in cassava. Biochemical analyses reveal that shoot-propagated cassava with GB03-inoculation exhibit elevated iron accumulation after 140 days of plant growth as determined by X-ray microanalysis and total foliar iron analysis. Growth promotion and increased photosynthetic efficiency were also observed for greenhouse-grown plants with GB03-exposure. These results demonstrate the potential of microbes to increase iron accumulation in an important agricultural crop and is consistent with idea that microbial signaling can regulate plant photosynthesis. PMID:26300897

  8. Genome Sequence of Pseudomonas chlororaphis Strain PA23

    PubMed Central

    Loewen, Peter C.; Villenueva, Jacylyn; Fernando, W. G. Dilantha

    2014-01-01

    Pseudomonas chlororaphis strain PA23 is a plant-beneficial bacterium that is able to suppress disease caused by the fungal pathogen Sclerotinia sclerotiorum through a process known as biological control. Here we present a 7.1-Mb assembly of the PA23 genome. PMID:25035328

  9. Pseudomonas screening assay

    NASA Technical Reports Server (NTRS)

    Margalit, Ruth (Inventor)

    1993-01-01

    A method for the detection of Pseudomonas bacteria is described where an Azurin-specific antibody is employed for detecting the presence of Azurin in a test sample. The detection of the presence of Azurin in the sample is a conclusive indicator of the presence of the Pseudomonas bacteria since the Azurin protein is a specific marker for this bacterial strain.

  10. Recombineering Pseudomonas syringae

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Here we report the identification of functions that promote genomic recombination of linear DNA introduced into Pseudomonas cells by electroporation. The genes encoding these functions were identified in Pseudomonas syringae pv. syringae B728a based on similarity to the lambda Red Exo/Beta and RecE...

  11. Biodegradation of chlorpyrifos by bacterial genus Pseudomonas.

    PubMed

    Gilani, Razia Alam; Rafique, Mazhar; Rehman, Abdul; Munis, Muhammad Farooq Hussain; Rehman, Shafiq Ur; Chaudhary, Hassan Javed

    2016-02-01

    Chlorpyrifos is an organophosphorus pesticide commonly used in agriculture. It is noxious to a variety of organisms that include living soil biota along with beneficial arthropods, fish, birds, humans, animals, and plants. Exposure to chlorpyrifos may cause detrimental effects as delayed seedling emergence, fruit deformities, and abnormal cell division. Contamination of chlorpyrifos has been found about 24 km from the site of its application. There are many physico-chemical and biological approaches to remove organophosphorus pesticides from the ecosystem, among them most promising is biodegradation. The 3,5,6-trichloro-2-pyridinol (TCP) and diethylthiophosphate (DETP) as primary products are made when chlorpyrifos is degraded by soil microorganisms which further break into nontoxic metabolites as CO(2), H(2)O, and NH(3). Pseudomonas is a diversified genus possessing a series of catabolic pathways and enzymes involved in pesticide degradation. Pseudomonas putida MAS-1 is reported to be more efficient in chlorpyrifos degradation by a rate of 90% in 24 h among Pseudomonas genus. The current review analyzed the comparative potential of bacterial species in Pseudomonas genus for degradation of chlorpyrifos thus, expressing an ecofriendly approach for the treatment of environmental contaminants like pesticides.

  12. Biodegradation of chlorpyrifos by bacterial genus Pseudomonas.

    PubMed

    Gilani, Razia Alam; Rafique, Mazhar; Rehman, Abdul; Munis, Muhammad Farooq Hussain; Rehman, Shafiq Ur; Chaudhary, Hassan Javed

    2016-02-01

    Chlorpyrifos is an organophosphorus pesticide commonly used in agriculture. It is noxious to a variety of organisms that include living soil biota along with beneficial arthropods, fish, birds, humans, animals, and plants. Exposure to chlorpyrifos may cause detrimental effects as delayed seedling emergence, fruit deformities, and abnormal cell division. Contamination of chlorpyrifos has been found about 24 km from the site of its application. There are many physico-chemical and biological approaches to remove organophosphorus pesticides from the ecosystem, among them most promising is biodegradation. The 3,5,6-trichloro-2-pyridinol (TCP) and diethylthiophosphate (DETP) as primary products are made when chlorpyrifos is degraded by soil microorganisms which further break into nontoxic metabolites as CO(2), H(2)O, and NH(3). Pseudomonas is a diversified genus possessing a series of catabolic pathways and enzymes involved in pesticide degradation. Pseudomonas putida MAS-1 is reported to be more efficient in chlorpyrifos degradation by a rate of 90% in 24 h among Pseudomonas genus. The current review analyzed the comparative potential of bacterial species in Pseudomonas genus for degradation of chlorpyrifos thus, expressing an ecofriendly approach for the treatment of environmental contaminants like pesticides. PMID:26837064

  13. Pseudomonas grimontii sp. nov.

    PubMed

    Baïda, Nader; Yazourh, Asmae; Singer, Elisabeth; Izard, Daniel

    2002-09-01

    The vernacular name 'fluorescent Pseudomonas group 97-514' was coined for a group of 43 strains isolated from two French natural mineral waters. All these strains were gram-negative, rod-shaped and motile by means of a single polar flagellum. They produced fluorescent pigment (pyoverdin) on King B medium, catalase and cytochrome oxidase. They were capable of respiratory but not fermentative metabolism. They were not able to accumulate poly-beta-hydroxybutyrate and possessed an arginine dihydrolase system. DNA-DNA relatedness studies (S1 nuclease method) showed that the 43 strains of 'fluorescent Pseudomonas group 97-514' formed a genetically homogeneous group (DNA-DNA relatedness ranged from 70 to 100%). A total of 76 strains representing well-known or partially characterized species of the genus Pseudomonas sensu stricto had 7-56% DNA hybridization with strain CFML 97-514T. The highest DNA binding values were found with Pseudomonas veronii CIP 104663T (52%), Pseudomonas rhodesiae CIP 104664T (56%), Pseudomonas marginalis ATCC 10844T (56%), Pseudomonas gessardii CIP 105469T (53%) and Pseudomonas cedrella CIP 105541T (52%). Their unrelatedness was confirmed by deltaTm values greater than 7 degrees C. On the basis of the results of phenotypic and DNA-DNA hybridization studies, a novel Pseudomonas species, Pseudomonas grimontii sp. nov., is proposed for the 43 strains of 'fluorescent Pseudomonas group 97-514'. The type strain is strain CFML 97-514T (= CIP 106645T = ATCC BAA-140T). The G+C content of the DNA of the type strain was 58 mol%. A comparison of the complete 16S rRNA gene sequence of the type strain CFML 97-514T and the sequence of other strains of the genus Pseudomonas revealed that the novel species fell within the 'Pseudomonas fluorescens intrageneric cluster'. Members of P. grimontii grew at 4 degrees C but not at 41 degrees C. They were able to use D-xylose, alpha-L-rhamnose, alpha-aminobutyrate, meso-erythritol and itaconate as sole sources of carbon

  14. Induction of drought tolerance in cucumber plants by a consortium of three plant growth-promoting rhizobacterium strains.

    PubMed

    Wang, Chun-Juan; Yang, Wei; Wang, Chao; Gu, Chun; Niu, Dong-Dong; Liu, Hong-Xia; Wang, Yun-Peng; Guo, Jian-Hua

    2012-01-01

    Our previous work showed that a consortium of three plant growth-promoting rhizobacterium (PGPR) strains (Bacillus cereus AR156, Bacillus subtilis SM21, and Serratia sp. XY21), termed as BBS for short, was a promising biocontrol agent. The present study investigated its effect on drought tolerance in cucumber plants. After withholding watering for 13 days, BBS-treated cucumber plants had much darker green leaves and substantially lighter wilt symptoms than control plants. Compared to the control, the BBS treatment decreased the leaf monodehydroascorbate (MDA) content and relative electrical conductivity by 40% and 15%, respectively; increased the leaf proline content and the root recovery intension by 3.45-fold and 50%, respectively; and also maintained the leaf chlorophyll content in cucumber plants under drought stress. Besides, in relation to the control, the BBS treatment significantly enhanced the superoxide dismutase (SOD) activity and mitigated the drought-triggered down-regulation of the expression of the genes cAPX, rbcL, and rbcS encoding cytosolic ascorbate peroxidase, and ribulose-1,5-bisphosphate carboxy/oxygenase (Rubisco) large and small subunits, respectively, in cucumber leaves. However, 1-aminocyclopropane-1-carboxylate (ACC) deaminase activity was undetected in none of the culture solutions of three BBS constituent strains. These results indicated that BBS conferred induced systemic tolerance to drought stress in cucumber plants, by protecting plant cells, maintaining photosynthetic efficiency and root vigor and increasing some of antioxidase activities, without involving the action of ACC deaminase to lower plant ethylene levels.

  15. Bacteriophytochrome controls carotenoid-independent response to photodynamic stress in a non-photosynthetic rhizobacterium, Azospirillum brasilense Sp7.

    PubMed

    Kumar, Santosh; Kateriya, Suneel; Singh, Vijay Shankar; Tanwar, Meenakshi; Agarwal, Shweta; Singh, Hina; Khurana, Jitendra Paul; Amla, Devinder Vijay; Tripathi, Anil Kumar

    2012-01-01

    Ever since the discovery of the role of bacteriophytochrome (BphP) in inducing carotenoid synthesis in Deinococcus radiodurans in response to light the role of BphPs in other non-photosynthetic bacteria is not clear yet. Azospirillum brasilense, a non-photosynthetic rhizobacterium, harbours a pair of BphPs out of which AbBphP1 is a homolog of AtBphP1 of Agrobacterium tumefaciens. By overexpression, purification, biochemical and spectral characterization we have shown that AbBphP1 is a photochromic bacteriophytochrome. Phenotypic study of the ΔAbBphP1 mutant showed that it is required for the survival of A. brasilense on minimal medium under red light. The mutant also showed reduced chemotaxis towards dicarboxylates and increased sensitivity to the photooxidative stress. Unlike D. radiodurans, AbBphP1 was not involved in controlling carotenoid synthesis. Proteome analysis of the ΔAbBphP1 indicated that AbBphP1 is involved in inducing a cellular response that enables A. brasilense in regenerating proteins that might be damaged due to photodynamic stress.

  16. Managing urban biosolids: Beneficial uses

    SciTech Connect

    Forste, J.B.

    1998-07-01

    Biosolids (the primarily organic product produced by wastewater treatment processes that can be beneficially recycled) are becoming a significant challenge for operators of both small and large urban wastewater facilities. More stringent water quality standards, coupled with increasingly sensitive environmental and public health considerations, have made the treatment and use/disposal of solids from treatment processes a growing and complex field of environmental management.

  17. Beneficial Uses of Depleted Uranium

    SciTech Connect

    Brown, C.; Croff, A.G.; Haire, M. J.

    1997-08-01

    Naturally occurring uranium contains 0.71 wt% {sup 235}U. In order for the uranium to be useful in most fission reactors, it must be enriched the concentration of the fissile isotope {sup 235}U must be increased. Depleted uranium (DU) is a co-product of the processing of natural uranium to produce enriched uranium, and DU has a {sup 235}U concentration of less than 0.71 wt%. In the United States, essentially all of the DU inventory is in the chemical form of uranium hexafluoride (UF{sub 6}) and is stored in large cylinders above ground. If this co-product material were to be declared surplus, converted to a stable oxide form, and disposed, the costs are estimated to be several billion dollars. Only small amounts of DU have at this time been beneficially reused. The U.S. Department of Energy (DOE) has begun the Beneficial Uses of DU Project to identify large-scale uses of DU and encourage its reuse for the primary purpose of potentially reducing the cost and expediting the disposition of the DU inventory. This paper discusses the inventory of DU and its rate of increase; DU disposition options; beneficial use options; a preliminary cost analysis; and major technical, institutional, and regulatory issues to be resolved.

  18. Indicator For Pseudomonas Bacteria

    NASA Technical Reports Server (NTRS)

    Margalit, Ruth

    1990-01-01

    Characteristic protein extracted and detected. Natural protein marker found in Pseudomonas bacteria. Azurin, protein containing copper readily extracted, purified, and used to prepare antibodies. Possible to develop simple, fast, and accurate test for marker carried out in doctor's office.

  19. Comparative genomic analysis of four representative plant growth-promoting rhizobacteria in Pseudomonas

    PubMed Central

    2013-01-01

    Background Some Pseudomonas strains function as predominant plant growth-promoting rhizobacteria (PGPR). Within this group, Pseudomonas chlororaphis and Pseudomonas fluorescens are non-pathogenic biocontrol agents, and some Pseudomonas aeruginosa and Pseudomonas stutzeri strains are PGPR. P. chlororaphis GP72 is a plant growth-promoting rhizobacterium with a fully sequenced genome. We conducted a genomic analysis comparing GP72 with three other pseudomonad PGPR: P. fluorescens Pf-5, P. aeruginosa M18, and the nitrogen-fixing strain P. stutzeri A1501. Our aim was to identify the similarities and differences among these strains using a comparative genomic approach to clarify the mechanisms of plant growth-promoting activity. Results The genome sizes of GP72, Pf-5, M18, and A1501 ranged from 4.6 to 7.1 M, and the number of protein-coding genes varied among the four species. Clusters of Orthologous Groups (COGs) analysis assigned functions to predicted proteins. The COGs distributions were similar among the four species. However, the percentage of genes encoding transposases and their inactivated derivatives (COG L) was 1.33% of the total genes with COGs classifications in A1501, 0.21% in GP72, 0.02% in Pf-5, and 0.11% in M18. A phylogenetic analysis indicated that GP72 and Pf-5 were the most closely related strains, consistent with the genome alignment results. Comparisons of predicted coding sequences (CDSs) between GP72 and Pf-5 revealed 3544 conserved genes. There were fewer conserved genes when GP72 CDSs were compared with those of A1501 and M18. Comparisons among the four Pseudomonas species revealed 603 conserved genes in GP72, illustrating common plant growth-promoting traits shared among these PGPR. Conserved genes were related to catabolism, transport of plant-derived compounds, stress resistance, and rhizosphere colonization. Some strain-specific CDSs were related to different kinds of biocontrol activities or plant growth promotion. The GP72 genome

  20. Electrostatic Beneficiation of Lunar Simulant

    NASA Technical Reports Server (NTRS)

    Trigwell, Steve; Captain, James; Captain, Janine; Arens, Ellen; Quinn, Jacqueline; Calle, Carlos

    2006-01-01

    Electrostatic beneficiation of lunar regolith is a method allowing refinement of specific minerals in the material for processing on the moon. The use of tribocharging the regolith prior to separation was investigated on the lunar simulant MLS-I by passing the dust through static mixers constructed from different materials; aluminum, copper, stainless steel, and polytetrafluoroethylene (PTFE). The amount of charge acquired by the simulant was dependent upon the difference in the work function of the dust and the charging material. XPS and SEM were used to characterize the simulant after it was sieved into five size fractions (> 100 pm, 75-100 pm, 50- 75 pm, 50-25 pm, and < 25 pm), where very little difference in surface composition was observed between the sizes. Samples of the smallest (< 25 pm) and largest (> 100 pm) size fractions were beneficiated through a charge separator using the aluminum (charged the simulant negatively) and PTFE (charged positively) mixers. The mass fractions of the separated simulant revealed that for the larger particle size, significant unipolar charging was observed for both mixers, whereas for the smaller particle sizes, more bipolar charging was observed, probably due to the finer simulant adhering to the inside of the mixers shielding the dust from the charging material. Subsequent XPS analysis of the beneficiated fractions showed the larger particle size fraction having some species differentiation, but very little difference for the smaller.size. Although MLS-1 was made to have similar chemistry to actual lunar dust, its mineralogy is quite different. On-going experiments are using NASA JSC-1 lunar simulant. A vacuum chamber has been constructed, and future experiments are planned in a simulated lunar environment.

  1. Induction of Drought Tolerance in Cucumber Plants by a Consortium of Three Plant Growth-Promoting Rhizobacterium Strains

    PubMed Central

    Wang, Chao; Gu, Chun; Niu, Dong-Dong; Liu, Hong-Xia; Wang, Yun-Peng; Guo, Jian-Hua

    2012-01-01

    Our previous work showed that a consortium of three plant growth-promoting rhizobacterium (PGPR) strains (Bacillus cereus AR156, Bacillus subtilis SM21, and Serratia sp. XY21), termed as BBS for short, was a promising biocontrol agent. The present study investigated its effect on drought tolerance in cucumber plants. After withholding watering for 13 days, BBS-treated cucumber plants had much darker green leaves and substantially lighter wilt symptoms than control plants. Compared to the control, the BBS treatment decreased the leaf monodehydroascorbate (MDA) content and relative electrical conductivity by 40% and 15%, respectively; increased the leaf proline content and the root recovery intension by 3.45-fold and 50%, respectively; and also maintained the leaf chlorophyll content in cucumber plants under drought stress. Besides, in relation to the control, the BBS treatment significantly enhanced the superoxide dismutase (SOD) activity and mitigated the drought-triggered down-regulation of the expression of the genes cAPX, rbcL, and rbcS encoding cytosolic ascorbate peroxidase, and ribulose-1,5-bisphosphate carboxy/oxygenase (Rubisco) large and small subunits, respectively, in cucumber leaves. However, 1-aminocyclopropane-1-carboxylate (ACC) deaminase activity was undetected in none of the culture solutions of three BBS constituent strains. These results indicated that BBS conferred induced systemic tolerance to drought stress in cucumber plants, by protecting plant cells, maintaining photosynthetic efficiency and root vigor and increasing some of antioxidase activities, without involving the action of ACC deaminase to lower plant ethylene levels. PMID:23285089

  2. Comparative Genomic Analysis of Pseudomonas chlororaphis PCL1606 Reveals New Insight into Antifungal Compounds Involved in Biocontrol.

    PubMed

    Calderón, Claudia E; Ramos, Cayo; de Vicente, Antonio; Cazorla, Francisco M

    2015-03-01

    Pseudomonas chlororaphis PCL1606 is a rhizobacterium that has biocontrol activity against many soilborne phytopathogenic fungi. The whole genome sequence of this strain was obtained using the Illumina Hiseq 2000 sequencing platform and was assembled using SOAP denovo software. The resulting 6.66-Mb complete sequence of the PCL1606 genome was further analyzed. A comparative genomic analysis using 10 plant-associated strains within the fluorescent Pseudomonas group, including the complete genome of P. chlororaphis PCL1606, revealed a diverse spectrum of traits involved in multitrophic interactions with plants and microbes as well as biological control. Phylogenetic analysis of these strains using eight housekeeping genes clearly placed strain PCL1606 into the P. chlororaphis group. The genome sequence of P. chlororaphis PCL1606 revealed the presence of sequences that were homologous to biosynthetic genes for the antifungal compounds 2-hexyl, 5-propyl resorcinol (HPR), hydrogen cyanide, and pyrrolnitrin; this is the first report of pyrrolnitrin encoding genes in this P. chlororaphis strain. Single-, double-, and triple-insertional mutants in the biosynthetic genes of each antifungal compound were used to test their roles in the production of these antifungal compounds and in antagonism and biocontrol of two fungal pathogens. The results confirmed the function of HPR in the antagonistic phenotype and in the biocontrol activity of P. chlororaphis PCL1606.

  3. Comparative Genomic Analysis of Pseudomonas chlororaphis PCL1606 Reveals New Insight into Antifungal Compounds Involved in Biocontrol.

    PubMed

    Calderón, Claudia E; Ramos, Cayo; de Vicente, Antonio; Cazorla, Francisco M

    2015-03-01

    Pseudomonas chlororaphis PCL1606 is a rhizobacterium that has biocontrol activity against many soilborne phytopathogenic fungi. The whole genome sequence of this strain was obtained using the Illumina Hiseq 2000 sequencing platform and was assembled using SOAP denovo software. The resulting 6.66-Mb complete sequence of the PCL1606 genome was further analyzed. A comparative genomic analysis using 10 plant-associated strains within the fluorescent Pseudomonas group, including the complete genome of P. chlororaphis PCL1606, revealed a diverse spectrum of traits involved in multitrophic interactions with plants and microbes as well as biological control. Phylogenetic analysis of these strains using eight housekeeping genes clearly placed strain PCL1606 into the P. chlororaphis group. The genome sequence of P. chlororaphis PCL1606 revealed the presence of sequences that were homologous to biosynthetic genes for the antifungal compounds 2-hexyl, 5-propyl resorcinol (HPR), hydrogen cyanide, and pyrrolnitrin; this is the first report of pyrrolnitrin encoding genes in this P. chlororaphis strain. Single-, double-, and triple-insertional mutants in the biosynthetic genes of each antifungal compound were used to test their roles in the production of these antifungal compounds and in antagonism and biocontrol of two fungal pathogens. The results confirmed the function of HPR in the antagonistic phenotype and in the biocontrol activity of P. chlororaphis PCL1606. PMID:25679537

  4. Responses of unsaturated Pseudomonas putida CZ1 biofilms to environmental stresses in relation to the EPS composition and surface morphology.

    PubMed

    Lin, Huirong; Chen, Guangcun; Long, Dongyan; Chen, Xincai

    2014-12-01

    The extracellular polymeric substance (EPS) and surface properties of unsaturated biofilms of a heavy metal-resistant rhizobacterium Pseudomonas putida CZ1, in response to aging, pH, temperature and osmotic stress, were studied by quantitative analysis of EPS and atomic force microscope. It was found that EPS production increased approximately linearly with culture time, cells in the air-biofilm interface enhanced EPS production and decreased cell volume to cope with nutrient depletion during aging. Low pH, high temperature and certain osmotic stress (120 mM NaCl) distinctly stimulated EPS production, and the main component enhanced was extracellular protein. In addition to the enhancement of EPS production in response to high osmotic (328 mM NaCl) stress, cells in the biofilm adhere tightly together to maintain a particular microenvironment. These results indicated the variation of EPS composition and the cooperation of cells in the biofilms is important for the survival of Pseudomonas putida CZ1 from environmental stresses in the unsaturated environments such as rhizosphere.

  5. Hot Tub Rash (Pseudomonas Folliculitis)

    MedlinePlus

    ... rash and rashes clinical tools newsletter | contact Share | Hot Tub Rash ( Pseudomonas Folliculitis) Information for adults A ... the skin and small pus-filled lesions. Overview Hot tub rash ( Pseudomonas folliculitis) is an infection of ...

  6. Coal beneficiation by gas agglomeration

    DOEpatents

    Wheelock, Thomas D.; Meiyu, Shen

    2003-10-14

    Coal beneficiation is achieved by suspending coal fines in a colloidal suspension of microscopic gas bubbles in water under atmospheric conditions to form small agglomerates of the fines adhered by the gas bubbles. The agglomerates are separated, recovered and resuspended in water. Thereafter, the pressure on the suspension is increased above atmospheric to deagglomerate, since the gas bubbles are then re-dissolved in the water. During the deagglomeration step, the mineral matter is dispersed, and when the pressure is released, the coal portion of the deagglomerated gas-saturated water mixture reagglomerates, with the small bubbles now coming out of the solution. The reagglomerate can then be separated to provide purified coal fines without the mineral matter.

  7. Wastewater privatization: A beneficial alternative

    SciTech Connect

    Wakeman, R.F.; Drewry, W.A.

    1999-07-01

    Municipalities with wastewater operations face increasing requirements to maximize efficiency, implement capital improvements, and ensure environmental compliance. Privatization is a relatively unused alternative offering benefits in the areas of cost-effective operations, flexible financing, technology access, and compliance assurance. Recent executive direction and tax code changes have opened new doors for mutually beneficial public-private partnerships. Wastewater privatization has historically consisted of short-term contract agreements for treatment operations, but looming infrastructure recapitalization and development requirements have catalyzed an exploration of non-traditional alternatives that include private sector financing, development, and operation of entire wastewater systems, The purpose of this paper is to show why privatization must be considered, evaluate the different levels available, and generate an analytical aid for communities taking their first look at privatization opportunities.

  8. Polymicrobial Ventriculitis Involving Pseudomonas fulva

    PubMed Central

    Rebolledo, Paulina A.; Vu, Catphuong Cathy L.; Carlson, Renee Donahue; Kraft, Colleen S.; Anderson, Evan J.

    2014-01-01

    Infections due to Pseudomonas fulva remain a rare but emerging concern. A case of ventriculitis due to Enterobacter cloacae and Pseudomonas fulva following placement of an external ventricular drain is described. Similar to other reports, the organism was initially misidentified as Pseudomonas putida. The infection was successfully treated with levofloxacin. PMID:24648556

  9. Pseudomonas psychrotolerans sp. nov.

    PubMed

    Hauser, Elke; Kämpfer, Peter; Busse, Hans-Jürgen

    2004-09-01

    Three yellow-pigmented, Gram-negative, rod-shaped, non-spore-forming bacterial strains, C36T, C37 and C39, were isolated in the Medical Clinic for Small Animals and Ungulates at the University for Veterinary Medicine in Vienna, Austria. On the basis of 16S rRNA gene sequence similarity, strain C36T was shown to belong to the genus Pseudomonas; Pseudomonas oleovorans DSM 1045T was the nearest relative (99.5 % sequence similarity). Other Pseudomonas species shared <97 % sequence similarity with strain C36T. The presence of Q-9 as the major ubiquinone, the predominance of putrescine and spermidine in its polyamine patterns and its fatty acid profile [i.e. the predominance of C(16 : 0), summed feature 3 (C(16 : 1)omega7c and/or 2-OH C(15 : 0) iso), C(18 : 1)omega7c and the presence of 3-OH C(10 : 0), 3-OH C(12 : 0) and 2-OH C(12 : 0)] were in agreement with identification of this strain as a member of the genus Pseudomonas. Physiological and biochemical characteristics and the results of genomic fingerprinting clearly differentiated strain C36T from its phylogenetic relative P. oleovorans DSM 1045T. Results from DNA-DNA hybridization showed that strain C36T represents a species that is distinct from P. oleovorans DSM 1045T. These data demonstrate that strain C36T represents a novel species of the genus Pseudomonas, for which the name Pseudomonas psychrotolerans sp. nov. is proposed. The type strain is C36T (= LMG 21977T = DSM 15758T). Additionally, physiological, biochemical, chemotaxonomic and genomic fingerprints indicate that P. oleovorans ATCC 29347 may not be a member of the species P. oleovorans sensu stricto. PMID:15388721

  10. Biocontrol activity of Paenibacillus polymyxa AC-1 against Pseudomonas syringae and its interaction with Arabidopsis thaliana.

    PubMed

    Hong, Chi Eun; Kwon, Suk Yoon; Park, Jeong Mee

    2016-04-01

    Paenibacillus polymyxa AC-1 (AC-1) is a plant growth-promoting rhizobacterium (PGPR) that has been used as a soil inoculant for biocontrol of plant pathogenic fungi and to promote plant growth. In this study, we examine the effects of AC-1 on the bacterial phytopathogen Pseudomonas syringae and internal colonization of AC-1 by counting bacterial populations that colonize plants. AC-1 inhibited the growth of both P. syringae pv. tomato DC3000 (Pst) and P. syringae pv. tabaci (Pta) in a concentration-dependent manner in in vitro assays. Upon treatment of AC-1 dropping at root tip of axenically grown Arabidopsis, we found that most of the AC-1 was detected in interior of leaves of Arabidiopsis plants rather than roots after 5 days post infection, indicating systemic spreading of AC-1 occur. We examined further AC-1 colonization patterns in Arabidopsis mutants deficient in phytohormone signaling pathways. These results indicated that abscisic acid (ABA) and jasmonic acid (JA) signaling pathways positively and negatively contributed, respectively, to AC-1 colonization of leaves, whereas epiphytic accumulation of AC-1 around root tissues was not affected. This study shows that AC-1 is an effective biocontrol agent to suppress P. syringae growth, possibly owing to its colonization patterns as a leaf-inhabiting endophyte. The results showed in this work will help to expand our understanding of the mode of action of AC-1 as a biological control agent and consequently, its application in agriculture.

  11. 7 CFR 1434.6 - Beneficial interest.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ..., title and control of the honey and beneficial interest in the honey, as specified in 7 CFR 1434.6, must... REGULATIONS FOR HONEY § 1434.6 Beneficial interest. (a) To be eligible to receive marketing assistance loans under this part a producer must have the beneficial interest in the honey that is tendered to CCC for...

  12. 7 CFR 1434.6 - Beneficial interest.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ..., title and control of the honey and beneficial interest in the honey, as specified in 7 CFR 1434.6, must... REGULATIONS FOR HONEY § 1434.6 Beneficial interest. (a) To be eligible to receive marketing assistance loans under this part a producer must have the beneficial interest in the honey that is tendered to CCC for...

  13. 7 CFR 1434.6 - Beneficial interest.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ..., title and control of the honey and beneficial interest in the honey, as specified in 7 CFR 1434.6, must... REGULATIONS FOR HONEY § 1434.6 Beneficial interest. (a) To be eligible to receive marketing assistance loans under this part a producer must have the beneficial interest in the honey that is tendered to CCC for...

  14. 7 CFR 1434.6 - Beneficial interest.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ..., title and control of the honey and beneficial interest in the honey, as specified in 7 CFR 1434.6, must... REGULATIONS FOR HONEY § 1434.6 Beneficial interest. (a) To be eligible to receive marketing assistance loans under this part a producer must have the beneficial interest in the honey that is tendered to CCC for...

  15. 7 CFR 1434.6 - Beneficial interest.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ..., title and control of the honey and beneficial interest in the honey, as specified in 7 CFR 1434.6, must... REGULATIONS FOR HONEY § 1434.6 Beneficial interest. (a) To be eligible to receive marketing assistance loans under this part a producer must have the beneficial interest in the honey that is tendered to CCC for...

  16. Optimizing Polychlorinated Biphenyl Degradation by Flavonoid-Induced Cells of the Rhizobacterium Rhodococcus erythropolis U23A.

    PubMed

    Pham, Thi Thanh My; Pino Rodriguez, Nancy Johanna; Hijri, Mohamed; Sylvestre, Michel

    2015-01-01

    There is evidence that many plant secondary metabolites may act as signal molecules to trigger the bacterial ability to metabolize polychlorinated biphenyls (PCBs) during the rhizoremediation process. However, the bases for the PCB rhizoremediation process are still largely unknown. The rhizobacterium Rhodococcus erythropolis U23A is unable to use flavanone as a growth substrate. However, on the basis of an assay that monitors the amount of 4-chlorobenzoate produced from 4-chlorobiphenyl by cells grown co-metabolically on flavanone plus sodium acetate, this flavonoid was previously found to be a potential inducer of the U23A biphenyl catabolic pathway. In this work, and using the same assay, we identified ten other flavonoids that did not support growth, but that acted as inducers of the U23A biphenyl pathway, and we confirmed flavonoid induction of the biphenyl catabolic pathway using quantitative real-time polymerase chain reaction (RT-qPCR) on the bphA gene. We also examined the effect of the growth co-substrate on flavonoid induction. Sodium acetate was replaced by glucose, mannose, sucrose, or mannitol, which are sugars found in plant root exudates. The data showed that the level of induction of strain U23A biphenyl-degrading enzymes was significantly influenced by the nature and concentration of the flavonoid in the growth medium, as well as by the substrate used for growth. Sucrose allowed for an optimal induction response for most flavonoids. Some flavonoids, such as flavone and isoflavone, were better inducers of the biphenyl catabolic enzymes than biphenyl itself. We also found that all flavonoids tested in this work were metabolized by strain U23A during co-metabolic growth, but that the metabolite profiles, as well as the level of efficiency of degradation, differed for each flavonoid. To obtain insight into how flavonoids interact with strain U23A to promote polychlorinated biphenyl (PCB) degradation, we determined the concentration of flavanone at

  17. Optimizing Polychlorinated Biphenyl Degradation by Flavonoid-Induced Cells of the Rhizobacterium Rhodococcus erythropolis U23A

    PubMed Central

    Hijri, Mohamed; Sylvestre, Michel

    2015-01-01

    There is evidence that many plant secondary metabolites may act as signal molecules to trigger the bacterial ability to metabolize polychlorinated biphenyls (PCBs) during the rhizoremediation process. However, the bases for the PCB rhizoremediation process are still largely unknown. The rhizobacterium Rhodococcus erythropolis U23A is unable to use flavanone as a growth substrate. However, on the basis of an assay that monitors the amount of 4-chlorobenzoate produced from 4-chlorobiphenyl by cells grown co-metabolically on flavanone plus sodium acetate, this flavonoid was previously found to be a potential inducer of the U23A biphenyl catabolic pathway. In this work, and using the same assay, we identified ten other flavonoids that did not support growth, but that acted as inducers of the U23A biphenyl pathway, and we confirmed flavonoid induction of the biphenyl catabolic pathway using quantitative real-time polymerase chain reaction (RT-qPCR) on the bphA gene. We also examined the effect of the growth co-substrate on flavonoid induction. Sodium acetate was replaced by glucose, mannose, sucrose, or mannitol, which are sugars found in plant root exudates. The data showed that the level of induction of strain U23A biphenyl-degrading enzymes was significantly influenced by the nature and concentration of the flavonoid in the growth medium, as well as by the substrate used for growth. Sucrose allowed for an optimal induction response for most flavonoids. Some flavonoids, such as flavone and isoflavone, were better inducers of the biphenyl catabolic enzymes than biphenyl itself. We also found that all flavonoids tested in this work were metabolized by strain U23A during co-metabolic growth, but that the metabolite profiles, as well as the level of efficiency of degradation, differed for each flavonoid. To obtain insight into how flavonoids interact with strain U23A to promote polychlorinated biphenyl (PCB) degradation, we determined the concentration of flavanone at

  18. Role of gluconic acid production in the regulation of biocontrol traits of Pseudomonas fluorescens CHA0.

    PubMed

    de Werra, Patrice; Péchy-Tarr, Maria; Keel, Christoph; Maurhofer, Monika

    2009-06-01

    The rhizobacterium Pseudomonas fluorescens CHA0 promotes the growth of various crop plants and protects them against root diseases caused by pathogenic fungi. The main mechanism of disease suppression by this strain is the production of the antifungal compounds 2,4-diacetylphloroglucinol (DAPG) and pyoluteorin (PLT). Direct plant growth promotion can be achieved through solubilization of inorganic phosphates by the production of organic acids, mainly gluconic acid, which is one of the principal acids produced by Pseudomonas spp. The aim of this study was to elucidate the role of gluconic acid production in CHA0. Therefore, mutants were created with deletions in the genes encoding glucose dehydrogenase (gcd) and gluconate dehydrogenase (gad), required for the conversion of glucose to gluconic acid and gluconic acid to 2-ketogluconate, respectively. These enzymes should be of predominant importance for rhizosphere-colonizing biocontrol bacteria, as major carbon sources provided by plant root exudates are made up of glucose. Our results show that the ability of strain CHA0 to acidify its environment and to solubilize mineral phosphate is strongly dependent on its ability to produce gluconic acid. Moreover, we provide evidence that the formation of gluconic acid by CHA0 completely inhibits the production of PLT and partially inhibits that of DAPG. In the Deltagcd mutant, which does not produce gluconic acid, the enhanced production of antifungal compounds was associated with improved biocontrol activity against take-all disease of wheat, caused by Gaeumannomyces graminis var. tritici. This study provides new evidence for a close association of gluconic acid metabolism with antifungal compound production and biocontrol activity in P. fluorescens CHA0.

  19. Study of the rhizobacterium Azospirillum brasilense Sp245 using Mössbauer spectroscopy with a high velocity resolution: Implication for the analysis of ferritin-like iron cores

    NASA Astrophysics Data System (ADS)

    Alenkina, I. V.; Oshtrakh, M. I.; Tugarova, A. V.; Biró, B.; Semionkin, V. A.; Kamnev, A. A.

    2014-09-01

    The results of a comparative study of two samples of the rhizobacterium Azospirillum brasilense (strain Sp245) prepared in different conditions and of human liver ferritin using Mössbauer spectroscopy with a high velocity resolution demonstrated the presence of ferritin-like iron (i.e. iron similar to that found in ferritin-like proteins) in the bacterium. Mössbauer spectra of these samples were fitted in two ways: as a rough approximation using a one quadrupole doublet fit (the homogeneous iron core model) and using a superposition of quadrupole doublets (the heterogeneous iron core model). Both results demonstrated differences in the Mössbauer parameters for mammalian ferritin and for bacterial ferritin-like iron. Moreover, some differences in the Mössbauer parameters were observed between the two samples of A. brasilense Sp245 related to the differences in their preparation conditions.

  20. 7 CFR 1421.6 - Beneficial interest.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... obtain beneficial interest to the commodity whether such purchase or acquisition is made prior to the... following language: Notwithstanding any other provision of this option to purchase or any other contract, title and control of the commodity and beneficial interest in the commodity as specified in 7 CFR...

  1. Involvement of Pyochelin and Pyoverdin in Suppression of Pythium-Induced Damping-Off of Tomato by Pseudomonas aeruginosa 7NSK2

    PubMed Central

    Buysens, S.; Heungens, K.; Poppe, J.; Hofte, M.

    1996-01-01

    The plant growth-promoting rhizobacterium Pseudomonas aeruginosa 7NSK2 produces three siderophores when iron is limited: the yellow-green fluorescent pyoverdin, the salicylate derivative pyochelin, and salicylic acid. This Pseudomonas strain was shown to be an efficient antagonist of Pythium-induced damping-off. The role of pyoverdin and pyochelin in the suppression of Pythium splendens was investigated by using various siderophore-deficient mutants derived from P. aeruginosa 7NSK2 in a bioassay with tomato (Lycopersicon esculentum). To provide more insight into the role of pyochelin in antagonism, mutant KMPCH, deficient in the production of pyoverdin and pyochelin, was complemented for pyochelin production. The complementing clone was further characterized by subcloning and transposon mutagenesis and used to generate a pyochelin-negative, pyoverdin-positive mutant by marker exchange. All mutants were able to reduce Pythium-induced preemergence damping-off to some extent. Production of either pyoverdin or pyochelin proved to be necessary to achieve wild-type levels of protection against Pythium-induced postemergence damping-off. Mutant KMPCH inhibited P. splendens but was less active than the parental strain. This residual protection could be due to the production of salicylic acid. Since pyoverdin and pyochelin are both siderophores, siderophore-mediated iron competition could explain the observed antagonism and the apparent interchangeability of the two compounds. We cannot, however, exclude the possibility that both siderophores act in an indirect way. PMID:16535275

  2. Pseudomonas genomes: diverse and adaptable.

    PubMed

    Silby, Mark W; Winstanley, Craig; Godfrey, Scott A C; Levy, Stuart B; Jackson, Robert W

    2011-07-01

    Members of the genus Pseudomonas inhabit a wide variety of environments, which is reflected in their versatile metabolic capacity and broad potential for adaptation to fluctuating environmental conditions. Here, we examine and compare the genomes of a range of Pseudomonas spp. encompassing plant, insect and human pathogens, and environmental saprophytes. In addition to a large number of allelic differences of common genes that confer regulatory and metabolic flexibility, genome analysis suggests that many other factors contribute to the diversity and adaptability of Pseudomonas spp. Horizontal gene transfer has impacted the capability of pathogenic Pseudomonas spp. in terms of disease severity (Pseudomonas aeruginosa) and specificity (Pseudomonas syringae). Genome rearrangements likely contribute to adaptation, and a considerable complement of unique genes undoubtedly contributes to strain- and species-specific activities by as yet unknown mechanisms. Because of the lack of conserved phenotypic differences, the classification of the genus has long been contentious. DNA hybridization and genome-based analyses show close relationships among members of P. aeruginosa, but that isolates within the Pseudomonas fluorescens and P. syringae species are less closely related and may constitute different species. Collectively, genome sequences of Pseudomonas spp. have provided insights into pathogenesis and the genetic basis for diversity and adaptation.

  3. Location and Survival of Mycorrhiza Helper Pseudomonas fluorescens during Establishment of Ectomycorrhizal Symbiosis between Laccaria bicolor and Douglas Fir

    PubMed Central

    Frey-Klett, P.; Pierrat, J. C.; Garbaye, J.

    1997-01-01

    The mycorrhiza helper bacterium Pseudomonas fluorescens BBc6, isolated from a Laccaria bicolor sporocarp, consistently promotes L. bicolor-Douglas fir (Pseudotsuga menziesii) ectomycorrhizal formation, even with low doses of bacterial inoculum. In order to describe this phenomenon more accurately, we have looked at the location and survival of the introduced bacterial strain in the soil and in the rhizosphere during the establishment of mycorrhizal symbiosis in glasshouse and nursery experiments. Bacterial populations were quantified with a spontaneous, stable, rifampin-resistant mutant, BBc6R8, which phenotypically conformed to the parental strain. BBc6R8 populations declined rapidly, reaching the detection limit after 19 weeks, and did not increase either when L. bicolor sporocarps were forming in autumn or when Douglas fir roots resumed growing in spring. BBc6R8 was neither an endophyte nor a rhizobacterium. Furthermore, it was not particularly associated with either mycorrhizas of Douglas fir-L. bicolor or L. bicolor sporocarps. Surprisingly, a significant mycorrhiza helper effect was observed when the inoculated BBc6R8 population had dropped as low as 30 CFU g of dry matter(sup-1) in the soil. This study raises questions concerning the bacterial concentration in the soil which is effective for promotion of mycorrhizal establishment and the timing of the bacterial effect. It allows us to develop working hypotheses, which can be tested experimentally, to identify the mechanisms of the mycorrhiza helper effect. PMID:16535478

  4. [Potentially beneficial effects of climate changes].

    PubMed

    Hitz, Mette Friberg; Jensen, Jens Erik Beck

    2009-10-26

    Climate changes have many unbeneficial effects on human health, but may also have beneficial effects. An increased mean temperature reduces the incidence of death due to hypothermia and cardiovascular disease and may increase exercise frequency. As the ozone layer decreases, the synthesis of vitamin D in the organism will also increase. An increased level of plasma vitamin D has beneficial effects on bone- and muscle health, seems to reduce cancer incidence and mortality and reduces the prevalence of autoimmune- and cardiovascular disease.

  5. Biology of Pseudomonas stutzeri

    PubMed Central

    Lalucat, Jorge; Bennasar, Antoni; Bosch, Rafael; García-Valdés, Elena; Palleroni, Norberto J.

    2006-01-01

    Pseudomonas stutzeri is a nonfluorescent denitrifying bacterium widely distributed in the environment, and it has also been isolated as an opportunistic pathogen from humans. Over the past 15 years, much progress has been made in elucidating the taxonomy of this diverse taxonomical group, demonstrating the clonality of its populations. The species has received much attention because of its particular metabolic properties: it has been proposed as a model organism for denitrification studies; many strains have natural transformation properties, making it relevant for study of the transfer of genes in the environment; several strains are able to fix dinitrogen; and others participate in the degradation of pollutants or interact with toxic metals. This review considers the history of the discovery, nomenclatural changes, and early studies, together with the relevant biological and ecological properties, of P. stutzeri. PMID:16760312

  6. Pseudomonas aeruginosa in Healthcare Settings

    MedlinePlus

    ... becoming more difficult to treat because of increasing antibiotic resistance. Selecting the right antibiotic usually requires that a ... to help educate people about Pseudomonas infections, and antibiotic resistance, and to encourage prevention activities and healthy behaviors ...

  7. Rhizobacterium-mediated growth promotion and expression of stress enzymes in Glycine max L. Merrill against Fusarium wilt upon challenge inoculation.

    PubMed

    Jain, Shekhar; Vaishnav, Anukool; Kasotia, Amrita; Kumari, Sarita; Gaur, Rajarshi Kumar; Choudhary, Devendra Kumar

    2014-02-01

    Wilt disease of soybean caused by a very common soil-borne fungus, Fusarium oxysporum is one of the most destructive diseases of the crop. The aim of the present study was to characterize plant growth-promotion activities and induced resistance of a rhizobacterial strain for the soybean plant against F. oxysporum. Rhizobacterium strain SJ-5 exhibited plant growth-promotion characteristics and antagonistic activity against the test pathogen on dual plate assay. It was identified as a Carnobacterium sp. A 950 bp PCR product was amplified from Carnobacterium sp. strain SJ-5, using zwittermicin A self-resistance gene-specific primers (zmaR). The strain produced indole 3-acetic acid (19 μg/ml) in the presence of salt stress and exhibited growth in Dworkin and Foster salt medium amended with 1-aminocyclopropane-1-carboxylate (ACC) through ACC deaminase activity (277 nmol/mg/h) as compared to the control. Strain seeds treated with the strain significantly enhanced the quorum of healthy plants after challenge inoculation at 14 days after seeding. An increase in the activity of stress enzymes after challenge inoculation with the test pathogen is reported. Treatment with the bacterium resulted in an increase in the chlorophyll content in the leaves in comparison with challenge-inoculated plants.

  8. Applying carbon dioxide, plant growth-promoting rhizobacterium and EDTA can enhance the phytoremediation efficiency of ryegrass in a soil polluted with zinc, arsenic, cadmium and lead.

    PubMed

    Guo, Junkang; Feng, Renwei; Ding, Yongzhen; Wang, Ruigang

    2014-08-01

    This study was conducted to investigate the use of elevated carbon dioxide (CO2), plant growth-promoting rhizobacterium Burkholderia sp. D54 (PGPR) and ethylenediaminetetraacetic acid (EDTA) to enhance the phytoextraction efficiency of ryegrass in response to multiple heavy metal (or metalloid)-polluted soil containing zinc (Zn), arsenic (As), cadmium (Cd) and lead (Pb). All of the single or combined CO2, PGPR and EDTA treatments promoted ryegrass growth. The stimulation of ryegrass growth by CO2 and PGPR could primarily be attributed to the regulation of photosynthesis rather than decreased levels of Zn, As and Cd in the shoots. Most treatments seemed to reduce the Zn, As and Cd contents in the shoots, which might be associated with enhanced shoot biomass, thus causing a "dilution effect" regarding their levels. The combined treatments seemed to perform better than single treatments in removing Zn, As, Cd and Pb from soil, judging from the larger biomass and relatively higher total amounts (TAs) of Zn, As, Cd and Pb in both the shoots and roots. Therefore, we suggest that the CO2 plus PGPR treatment will be suitable for removing Zn, As, Cd and Pb from heavy metal (or metalloid)-polluted soils using ryegrass as a phytoremediation material. PMID:24762567

  9. Regulation of expression and biochemical characterization of a beta-class carbonic anhydrase from the plant growth-promoting rhizobacterium, Azospirillum brasilense Sp7.

    PubMed

    Kaur, Simarjot; Mishra, Mukti Nath; Tripathi, Anil K

    2009-10-01

    Carbonic anhydrase (CA; [EC 4.2.1.1]) is a ubiquitous enzyme catalysing the reversible hydration of CO(2) to bicarbonate, a reaction that supports various biochemical and physiological functions. Genome analysis of Azospirillum brasilense, a nonphotosynthetic, nitrogen-fixing, rhizobacterium, revealed an ORF with homology to beta-class carbonic anhydrases (CAs). Biochemical characteristics of the beta-class CA of A. brasilense, analysed after cloning the gene (designated as bca), overexpressing in Escherichia coli and purifying the protein by affinity purification, revealed that the native recombinant enzyme is a homotetramer, inhibited by the known CA inhibitors. CA activity in A. brasilense cell extracts, reverse transcriptase (RT)-PCR and Western blot analyses showed that bca was constitutively expressed under aerobic conditions. Lower beta-galactosidase activity in A. brasilense cells harbouring bca promoter: lacZ fusion during the stationary phase or during growth on 3% CO(2) enriched air or at acidic pH indicated that the transcription of bca was downregulated by the stationary phase, elevated CO(2) levels and acidic pH conditions. These observations were also supported by RT-PCR analysis. Thus, beta-CA in A. brasilense seems to be required for scavenging CO(2) from the ambient air and the requirement of CO(2) hydration seems to be higher for the cultures growing exponentially at neutral to alkaline pH.

  10. RpoH2 sigma factor controls the photooxidative stress response in a non-photosynthetic rhizobacterium, Azospirillum brasilense Sp7.

    PubMed

    Kumar, Santosh; Rai, Ashutosh Kumar; Mishra, Mukti Nath; Shukla, Mansi; Singh, Pradhyumna Kumar; Tripathi, Anil Kumar

    2012-12-01

    Bacteria belonging to the Alphaproteobacteria normally harbour multiple copies of the heat shock sigma factor (known as σ(32), σ(H) or RpoH). Azospirillum brasilense, a non-photosynthetic rhizobacterium, harbours five copies of rpoH genes, one of which is an rpoH2 homologue. The genes around the rpoH2 locus in A. brasilense show synteny with that found in rhizobia. The rpoH2 of A. brasilense was able to complement the temperature-sensitive phenotype of the Escherichia coli rpoH mutant. Inactivation of rpoH2 in A. brasilense results in increased sensitivity to methylene blue and to triphenyl tetrazolium chloride (TTC). Exposure of A. brasilense to TTC and the singlet oxygen-generating agent methylene blue induced several-fold higher expression of rpoH2. Comparison of the proteome of A. brasilense with its rpoH2 deletion mutant and with an A. brasilense strain overexpressing rpoH2 revealed chaperone GroEL, elongation factors (Ef-Tu and EF-G), peptidyl prolyl isomerase, and peptide methionine sulfoxide reductase as the major proteins whose expression was controlled by RpoH2. Here, we show that the RpoH2 sigma factor-controlled photooxidative stress response in A. brasilense is similar to that in the photosynthetic bacterium Rhodobacter sphaeroides, but that RpoH2 is not involved in the detoxification of methylglyoxal in A. brasilense.

  11. An rpoD gene sequence based evaluation of cultured Pseudomonas diversity on different growth media.

    PubMed

    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.

  12. 7 CFR 1421.6 - Beneficial interest.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ..., feedlot, ethanol plant, wool pool, feed mill, feed or grain bank, or other facilities as determined by CCC... entities such as a dairy, feedlot, ethanol plant, wool pool, feed mill, feed or grain bank, or unauthorized..., title and control of the commodity and beneficial interest in the commodity as specified in 7 CFR...

  13. 7 CFR 1421.6 - Beneficial interest.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ..., feedlot, ethanol plant, wool pool, feed mill, feed or grain bank, or other facilities as determined by CCC... entities such as a dairy, feedlot, ethanol plant, wool pool, feed mill, feed or grain bank, or unauthorized..., title and control of the commodity and beneficial interest in the commodity as specified in 7 CFR...

  14. [Prebiotics: concept, properties and beneficial effects].

    PubMed

    Corzo, N; Alonso, J L; Azpiroz, F; Calvo, M A; Cirici, M; Leis, R; Lombó, F; Mateos-Aparicio, I; Plou, F J; Ruas-Madiedo, P; Rúperez, P; Redondo-Cuenca, A; Sanz, M L; Clemente, A

    2015-02-07

    Prebiotics are non-digestible food ingredients (oligosaccharides) that reach the colon and are used as substrate by microorganisms producing energy, metabolites and micronutrients used for the host; in addition they also stimulate the selective growth of certain beneficial species (mainly bifidobacteria and lactobacilli) in the intestinal microbiota. In this article, a multidisciplinary approach to understand the concept of prebiotic carbohydrates, their properties and beneficial effects in humans has been carried out. Definitions of prebiotics, reported by relevant international organizations and researchers, are described. A comprehensive description of accepted prebiotics having strong scientific evidence of their beneficial properties in humans (inulin-type fructans, FOS, GOS, lactulose and human milk oligosaccharides) is reported. Emerging prebiotics and those which are in the early stages of study have also included in this study. Taken into account that the chemical structure greatly influences carbohydrates prebiotic properties, the analytical techniques used for their analysis and characterization are discussed. In vitro and in vivo models used to evaluate the gastrointestinal digestion, absorption resistance and fermentability in the colon of prebiotics as well as major criteria to design robust intervention trials in humans are described. Finally, a comprehensive summary of the beneficial effects of prebiotics for health at systemic and intestinal levels is reported. The research effort on prebiotics has been intensive in last decades and has demonstrated that a multidisciplinary approach is necessary in order to claim their health benefits.

  15. The Roles of Beneficiation in Lunar Work

    NASA Technical Reports Server (NTRS)

    Rickman, Doug L.

    2010-01-01

    Natural feedstocks used for any process are intrinsically variable. They may also contain deleterious components or low concentrations of desired fractions. For these three reasons it is standard industrial practice to beneficiate feedstocks. This is true across all industries which trans-form raw materials into standardized units. On the Moon there are three natural resources: vacuum, radiation and regolith. To utilize in situ resources on the Moon it is reasonable to presume some beneficiation of the regolith (ground rock) resource will be desirable if not essential. As on Earth, this will require fundamental understanding of the physics and chemistry of the relevant processes, which are exceeding complex in detail. Further, simulants are essential test articles for evaluation of components and systems planned for lunar deployment. Simulants are of course made from geologic feedstocks. Therefore, there is variation, deleterious components and incorrect concentrations of desired fractions in the feedstocks used for simulants. Thus, simulant production can benefit from beneficiation of the input feedstocks. Beneficiation of geologic feedstocks is the subject of extractive metallurgy. Clearly, NASA has two discrete interests pertaining to the science and technology of extractive metallurgy.

  16. Beneficial Biofilms: Wastewater and Other Industrial Applications

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This chapter describes the use of beneficial biofilms for the production of industrial chemicals such as ethanol, butanol, lactic acid, acetic acid/vinegar, succinic acid, and fumaric acid. It also emphasizes application of biofilm reactors for treatment of dairy industry wastewater, oily sea water...

  17. 7 CFR 1421.6 - Beneficial interest.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ..., title and control of the commodity and beneficial interest in the commodity as specified in 7 CFR 1421.6..., feedlot, ethanol plant, wool pool, feed mill, feed or grain bank, or other facilities as determined by CCC... entities such as a dairy, feedlot, ethanol plant, wool pool, feed mill, feed or grain bank, or...

  18. Assessment of DAPG-producing Pseudomonas fluorescens for management of Meloidogyne incognita and Fusarium oxysporum on watermelon

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pseudomonas fluorescens isolates Clinto 1R, Wayne 1R and Wood 1R, which produce the antibiotic 2,4-diacetylphloroglucinol (DAPG), can suppress soilborne diseases and promote plant growth. Consequently, these beneficial bacterial isolates were tested on watermelon plants for suppression of Meloidogy...

  19. A type VI secretion system is involved in Pseudomonas fluorescens bacterial competition.

    PubMed

    Decoin, Victorien; Barbey, Corinne; Bergeau, Dorian; Latour, Xavier; Feuilloley, Marc G J; Orange, Nicole; Merieau, Annabelle

    2014-01-01

    Protein secretion systems are crucial mediators of bacterial interactions with other organisms. Among them, the type VI secretion system (T6SS) is widespread in Gram-negative bacteria and appears to inject toxins into competitor bacteria and/or eukaryotic cells. Major human pathogens, such as Vibrio cholerae, Burkholderia and Pseudomonas aeruginosa, express T6SSs. Bacteria prevent self-intoxication by their own T6SS toxins by producing immunity proteins, which interact with the cognate toxins. We describe here an environmental P. fluorescens strain, MFE01, displaying an uncommon oversecretion of Hcp (hemolysin-coregulated protein) and VgrG (valine-glycine repeat protein G) into the culture medium. These proteins are characteristic components of a functional T6SS. The aim of this study was to attribute a role to this energy-consuming overexpression of the T6SS. The genome of MFE01 contains at least two hcp genes (hcp1 and hcp2), suggesting that there may be two putative T6SS clusters. Phenotypic studies have shown that MFE01 is avirulent against various eukaryotic cell models (amebas, plant or animal cell models), but has antibacterial activity against a wide range of competitor bacteria, including rhizobacteria and clinical bacteria. Depending on the prey cell, mutagenesis of the hcp2 gene in MFE01 abolishes or reduces this antibacterial killing activity. Moreover, the introduction of T6SS immunity proteins from S. marcescens, which is not killed by MFE01, protects E. coli against MFE01 killing. These findings suggest that the protein encoded by hcp2 is involved in the killing activity of MFE01 mediated by effectors of the T6SS targeting the peptidoglycan of Gram-negative bacteria. Our results indicate that MFE01 can protect potato tubers against Pectobacterium atrosepticum, which causes tuber soft rot. Pseudomonas fluorescens is often described as a major PGPR (plant growth-promoting rhizobacterium), and our results suggest that there may be a connection between

  20. Process of beneficiating coal and product

    SciTech Connect

    Burgess, L.E.; Fox, K.M.; McGarry, P.E.

    1981-12-08

    Mine run coal is pulverized and the extended surfaces of the coal particles are rendered hydrophobic and oilophilic by a chemical bonding and graft polymerization reaction with a water unsoluble organic polymerizable monomer under peroxidation influence in a predominantly water reaction medium. The mineral ash present in the coal, particularly the iron pyrites, remains hydrophilic and is separated from the polymeric organic surface bonded coal product in a water washing step wherein the washed coal floats on and is recovered from the water phase and the ash is removed with the separated wash water in a critical wash step. The hydrophobic and oilophilic organic polymeric surface bonded coating about the coal particles is fortified by inclusion of additional unbound free fatty acids by further small additions thereof. Excess water is removed from the beneficiated hydrophobic surface-altered coal product mechanically, and the carboxylic acid groups present in the coal-oil product are thereafter converted to a metal soap. The beneficiated coal product can be used ''dry'', or additional quantities of a liquid hydrocarbon fuel can be incorporated with the ''dry'' beneficiated coal product to produce a flowable fluid or liquid coal product having the rheological property of marked thixotropy. Introduction of this physically induced property into the liquid coal-oil-mixture prevents settling out of the heavier coal particles from the relatively ash-free fluid fuel composition under extended storage periods.

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

    MedlinePlus

    Facts About “Hot Tub Rash” and “Swimmer’s Ear” (Pseudomonas) What is Pseudomonas and how can it affect me? Pseudomonas (sue-doh- ... a major cause of infections commonly known as “hot tub rash” and “swimmer’s ear.” This germ is ...

  2. Evidence for ferritin as dominant iron-bearing species in the rhizobacterium Azospirillum brasilense Sp7 provided by low-temperature/in-field Mössbauer spectroscopy.

    PubMed

    Kovács, Krisztina; Kamnev, Alexander A; Pechoušek, Jiří; Tugarova, Anna V; Kuzmann, Ernő; Machala, Libor; Zbořil, Radek; Homonnay, Zoltán; Lázár, Károly

    2016-02-01

    For the ubiquitous diazotrophic rhizobacterium Azospirillum brasilense, which has been attracting the attention of researchers worldwide for the last 35 years owing to its significant agrobiotechnological and phytostimulating potential, the data on iron acquisition and its chemical speciation in cells are scarce. In this work, for the first time for azospirilla, low-temperature (at 80 K, 5 K, as well as at 2 K without and with an external magnetic field of 5 T) transmission Mössbauer spectroscopic studies were performed for lyophilised biomass of A. brasilense (wild-type strain Sp7 grown with (57)Fe(III) nitrilotriacetate complex as the sole source of iron) to enable quantitative chemical speciation analysis of the intracellular iron. In the Mössbauer spectrum at 80 K, a broadened quadrupole doublet of high-spin iron(III) was observed with a few percent of a high-spin iron(II) contribution. In the spectrum measured at 5 K, a dominant magnetically split component appeared with the parameters typical of ferritin species from other bacteria, together with a quadrupole doublet of a superparamagnetic iron(III) component and a similarly small contribution from the high-spin iron(II) component. The Mössbauer spectra recorded at 2 K (with or without a 5 T external field) confirmed the assignment of ferritin species. About 20% of total Fe in the dry cells of A. brasilense strain Sp7 were present in iron(III) forms superparamagnetic at both 5 and 2 K, i.e. either different from ferritin cores or as ferritin components with very small particle sizes.

  3. Multiple impacts of the plant growth-promoting rhizobacterium Variovorax paradoxus 5C-2 on nutrient and ABA relations of Pisum sativum

    PubMed Central

    Dodd, Ian C.

    2012-01-01

    Resolving the physiological mechanisms by which rhizobacteria enhance plant growth is difficult, since many such bacteria contain multiple plant growth-promoting properties. To understand further how the 1-aminocyclopropane-1-carboxylate (ACC) deaminase (ACCd)-containing rhizobacterium Variovorax paradoxus 5C-2 affects plant growth, the flows and partitioning of mineral nutrients and abscisic acid (ABA) and ABA metabolism were studied in pea (Pisum sativum) plants following rhizosphere bacterial inoculation. Although root architecture was not affected, inoculation increased root and shoot biomass, and stomatal conductance, by 20, 15, and 24%, respectively, and increased N, P, K, Ca, and Mg uptake by 16, 81, 50, 46, and 58%, respectively. P deposition in inoculated plant roots was 4.9 times higher than that in uninoculated controls. Rhizobacterial inoculation increased root to shoot xylem flows and shoot to root phloem flows of K by 1.8- and 2.1-fold, respectively. In control plants, major sinks for K deposition were the roots and upper shoot (43% and 49% of total uptake, respectively), while rhizobacterial inoculation increased K distribution to the lower shoot at the expense of other compartments (xylem, phloem, and upper shoot). Despite being unable to metabolize ABA in vitro, V. paradoxus 5C-2 decreased root ABA concentrations and accumulation by 40–60%. Although inoculation decreased xylem ABA flows, phloem ABA flows increased. Whether bacterial ACCd attenuates root to shoot ABA signalling requires further investigation, since ABA is critical to maintain growth of droughted plants, and ACCd-containing organisms have been advocated as a means of minimizing growth inhibition of plants in drying soil. PMID:23136167

  4. Spaceflight promotes biofilm formation by Pseudomonas aeruginosa.

    PubMed

    Kim, Wooseong; Tengra, Farah K; Young, Zachary; Shong, Jasmine; Marchand, Nicholas; Chan, Hon Kit; Pangule, Ravindra C; Parra, Macarena; Dordick, Jonathan S; Plawsky, Joel L; Collins, Cynthia H

    2013-01-01

    Understanding the effects of spaceflight on microbial communities is crucial for the success of long-term, manned space missions. Surface-associated bacterial communities, known as biofilms, were abundant on the Mir space station and continue to be a challenge on the International Space Station. The health and safety hazards linked to the development of biofilms are of particular concern due to the suppression of immune function observed during spaceflight. While planktonic cultures of microbes have indicated that spaceflight can lead to increases in growth and virulence, the effects of spaceflight on biofilm development and physiology remain unclear. To address this issue, Pseudomonas aeruginosa was cultured during two Space Shuttle Atlantis missions: STS-132 and STS-135, and the biofilms formed during spaceflight were characterized. Spaceflight was observed to increase the number of viable cells, biofilm biomass, and thickness relative to normal gravity controls. Moreover, the biofilms formed during spaceflight exhibited a column-and-canopy structure that has not been observed on Earth. The increase in the amount of biofilms and the formation of the novel architecture during spaceflight were observed to be independent of carbon source and phosphate concentrations in the media. However, flagella-driven motility was shown to be essential for the formation of this biofilm architecture during spaceflight. These findings represent the first evidence that spaceflight affects community-level behaviors of bacteria and highlight the importance of understanding how both harmful and beneficial human-microbe interactions may be altered during spaceflight. PMID:23658630

  5. Role of 2-hexyl, 5-propyl resorcinol production by Pseudomonas chlororaphis PCL1606 in the multitrophic interactions in the avocado rhizosphere during the biocontrol process.

    PubMed

    Calderón, Claudia E; de Vicente, Antonio; Cazorla, Francisco M

    2014-07-01

    Different bacterial traits can contribute to the biocontrol of soilborne phytopathogenic fungus. Among others, (1) antagonism, (2) competition for nutrients and niches, (3) induction of systemic resistance of the plants and (4) predation and parasitism are the most studied. Pseudomonas chlororaphis PCL1606 is an antagonistic rhizobacterium that produces the antifungal metabolite 2-hexyl, 5-propyl resorcinol (HPR). This bacterium can biologically control the avocado white root rot caused by Rosellinia necatrix. Confocal laser scanning microscopy of the avocado rhizosphere revealed that this biocontrol bacterium and the fungal pathogen compete for the same niche and presumably also for root exudate nutrients. The use of derivative mutants in the geners related to HPR biosynthesis (dar genes) revealed that the lack of HPR production by P. chlororaphis PCL1606 negatively influences the bacterial colonisation of the avocado root surface. Microscopical analysis showed that P. chlororaphis PCL1606 closely interacts and colonises the fungal hyphae, which may represent a novel biocontrol mechanism in this pseudomonad. Additionally, the presence of HPR-producing biocontrol bacteria negatively affects the ability of the fungi to infect the avocado root. HPR production negatively affects hyphal growth, leading to alterations in the R. necatrix physiology visible under microscopy, including the curling, vacuolisation and branching of hyphae, which presumably affects the colonisation and infection abilities of the fungus. This study provides the first report of multitrophic interactions in the avocado rhizosphere, advancing our understanding of the role of HPR production in those interactions.

  6. A single mutation in the oprF mRNA leader confers strict translational control by the Gac/Rsm system in Pseudomonas fluorescens CHA0.

    PubMed

    Crespo, María Cecilia Alvarez; Valverde, Claudio

    2009-02-01

    The rhizobacterium Pseudomonas fluorescens CHA0 is able to antagonize fungal phytopathogens on a variety of crop plants, mainly due to the production of secondary metabolites that are coordinately upregulated by the global regulatory Gac/Rsm cascade. The two-component system GacS/GacA activates transcription of the three small regulatory RNAs RsmX, RsmY, and RsmZ, which counteract translational repression of target mRNAs by RsmA and RsmE proteins. In a search for novel Gac/Rsm targets based on the minimal sequence on mRNA leaders required for RsmA/RsmE control, the leader region of the major porin OprF emerged as a candidate. Although an isogenic CHA0 oprF mutant showed a reduced ability to attach to cucumber and tomato roots, suggesting a role for OprF in root colonization as a requisite for pathogen antagonism, a translational oprF'-'lacZ fusion was weakly regulated by Gac/Rsm despite its high sequence similarity to the hcnA leader. A single base substitution put the modified oprF 5'-UTR under strict control by Gac/Rsm. The results highlight the subtle sequence requirements of Gac/Rsm targets.

  7. Fernald scrap metal recycling and beneficial reuse

    SciTech Connect

    Motl, G.P.; Burns, D.D.

    1993-10-01

    The Fernald site, formerly the Feed Materials Production Facility, produced uranium metal products to meet defense production requirements for the Department of Energy from 1953 to 1989. In this report is is described how the Fernald scrap metal project has demonstrated that contractor capabilities can be used successfully to recycle large quantities of Department of Energy scrap metal. The project has proven that the {open_quotes}beneficial reuse{close_quotes} concept makes excellent economic sense when a market for recycled products can be identified. Topics covered in this report include the scrap metal pile history, the procurement strategy, scrap metal processing, and a discussion of lessons learned.

  8. Verticillium dahliae alters Pseudomonas spp. populations and HCN gene expression in the rhizosphere of strawberry.

    PubMed

    DeCoste, Nadine J; Gadkar, Vijay J; Filion, Martin

    2010-11-01

    The production of hydrogen cyanide (HCN) by beneficial root-associated bacteria is an important mechanism for the biological control of plant pathogens. However, little is known about the biotic factors affecting HCN gene expression in the rhizosphere of plants. In this study, real-time reverse transcription PCR (qRT-PCR) assays were developed to investigate the effect of the plant pathogen Verticillium dahliae on hcnC (encoding for HCN biosynthesis) gene expression in Pseudomonas sp. LBUM300. Strawberry plants were inoculated with Pseudomonas sp. LBUM300 and (or) V. dahliae and grown in pots filled with nonsterilized field soil. RNA was extracted from rhizosphere soil sampled at 0, 15, 30, and 45 days following inoculation with V. dahliae and used for qRT-PCR analyses. Populations of V. dahliae and Pseudomonas sp. LBUM300 were also monitored using a culture-independent qPCR approach. hcnC expression was detected at all sampling dates. The presence of V. dahliae had a significant stimulation effect on hcnC gene expression and also increased the population of Pseudomonas sp. LBUM300. However, the V. dahliae population was not altered by the presence of Pseudomonas sp. LBUM300. To our knowledge, this study is the first to evaluate the effect of a plant pathogen on HCN gene expression in the rhizosphere soil.

  9. Verticillium dahliae alters Pseudomonas spp. populations and HCN gene expression in the rhizosphere of strawberry.

    PubMed

    DeCoste, Nadine J; Gadkar, Vijay J; Filion, Martin

    2010-11-01

    The production of hydrogen cyanide (HCN) by beneficial root-associated bacteria is an important mechanism for the biological control of plant pathogens. However, little is known about the biotic factors affecting HCN gene expression in the rhizosphere of plants. In this study, real-time reverse transcription PCR (qRT-PCR) assays were developed to investigate the effect of the plant pathogen Verticillium dahliae on hcnC (encoding for HCN biosynthesis) gene expression in Pseudomonas sp. LBUM300. Strawberry plants were inoculated with Pseudomonas sp. LBUM300 and (or) V. dahliae and grown in pots filled with nonsterilized field soil. RNA was extracted from rhizosphere soil sampled at 0, 15, 30, and 45 days following inoculation with V. dahliae and used for qRT-PCR analyses. Populations of V. dahliae and Pseudomonas sp. LBUM300 were also monitored using a culture-independent qPCR approach. hcnC expression was detected at all sampling dates. The presence of V. dahliae had a significant stimulation effect on hcnC gene expression and also increased the population of Pseudomonas sp. LBUM300. However, the V. dahliae population was not altered by the presence of Pseudomonas sp. LBUM300. To our knowledge, this study is the first to evaluate the effect of a plant pathogen on HCN gene expression in the rhizosphere soil. PMID:21076481

  10. Tribocharging Lunar Soil for Electrostatic Beneficiation

    NASA Technical Reports Server (NTRS)

    2008-01-01

    Future human lunar habitation requires using in situ materials for both structural components and oxygen production. Lunar bases must be constructed from thermal-and radiation-shielding materials that will provide significant protection from the harmful cosmic energy which normally bombards the lunar surface. In addition, shipping oxygen from Earth is weight-prohibitive, and therefore investigating the production of breathable oxygen from oxidized mineral components is a major ongoing NASA research initiative. Lunar regolith may meet the needs for both structural protection and oxygen production. Already a number of oxygen production technologies are being tested, and full-scale bricks made of lunar simulant have been sintered. The beneficiation, or separation, of lunar minerals into a refined industrial feedstock could make production processes more efficient, requiring less energy to operate and maintain and producing higher-performance end products. The method of electrostatic beneficiation used in this research charges mineral powders (lunar simulant) by contact with materials of a different composition. The simulant acquires either a positive or negative charge depending upon its composition relative to the charging material.

  11. SRS stainless steel beneficial reuse program

    SciTech Connect

    Boettinger, W.L.

    1997-02-01

    The US Department of Energy`s (DOE) Savannah River Site (SRS) has thousands of tons of stainless steel radioactive scrap metal (RSNI). Much of the metal is volumetrically contaminated. There is no {open_quotes}de minimis{close_quotes} free release level for volumetric material, and therefore no way to recycle the metal into the normal commercial market. If declared waste, the metal would qualify as low level radioactive waste (LLW) and ultimately be dispositioned through shallow land buried at a cost of millions of dollars. The metal however could be recycled in a {open_quotes}controlled release{close_quote} manner, in the form of containers to hold other types of radioactive waste. This form of recycle is generally referred to as {open_quotes}Beneficial Reuse{close_quotes}. Beneficial reuse reduces the amount of disposal space needed and reduces the need for virgin containers which would themselves become contaminated. Stainless steel is particularly suited for long term storage because of its resistance to corrosion. To assess the practicality of stainless steel RSM recycle the SRS Benficial Reuse Program began a demonstration in 1994, funded by the DOE Office of Science and Technology. This paper discusses the experiences gained in this program.

  12. Type III secretion system and virulence markers highlight similarities and differences between human- and plant-associated pseudomonads related to Pseudomonas fluorescens and P. putida.

    PubMed

    Mazurier, Sylvie; Merieau, Annabelle; Bergeau, Dorian; Decoin, Victorien; Sperandio, Daniel; Crépin, Alexandre; Barbey, Corinne; Jeannot, Katy; Vicré-Gibouin, Maïté; Plésiat, Patrick; Lemanceau, Philippe; Latour, Xavier

    2015-04-01

    Pseudomonas fluorescens is commonly considered a saprophytic rhizobacterium devoid of pathogenic potential. Nevertheless, the recurrent isolation of strains from clinical human cases could indicate the emergence of novel strains originating from the rhizosphere reservoir, which could be particularly resistant to the immune system and clinical treatment. The importance of type three secretion systems (T3SSs) in the related Pseudomonas aeruginosa nosocomial species and the occurrence of this secretion system in plant-associated P. fluorescens raise the question of whether clinical isolates may also harbor T3SSs. In this study, isolates associated with clinical infections and identified in hospitals as belonging to P. fluorescens were compared with fluorescent pseudomonads harboring T3SSs isolated from plants. Bacterial isolates were tested for (i) their genetic relationships based on their 16S rRNA phylogeny, (ii) the presence of T3SS genes by PCR, and (iii) their infectious potential on animals and plants under environmental or physiological temperature conditions. Two groups of bacteria were delineated among the clinical isolates. The first group encompassed thermotolerant (41°C) isolates from patients suffering from blood infections; these isolates were finally found to not belong to P. fluorescens but were closely related and harbored highly conserved T3SS genes belonging to the Ysc-T3SS family, like the T3SSs from P. aeruginosa. The second group encompassed isolates from patients suffering from cystic fibrosis; these isolates belonged to P. fluorescens and harbored T3SS genes belonging to the Hrp1-T3SS family found commonly in plant-associated P. fluorescens.

  13. Type III secretion system and virulence markers highlight similarities and differences between human- and plant-associated pseudomonads related to Pseudomonas fluorescens and P. putida.

    PubMed

    Mazurier, Sylvie; Merieau, Annabelle; Bergeau, Dorian; Decoin, Victorien; Sperandio, Daniel; Crépin, Alexandre; Barbey, Corinne; Jeannot, Katy; Vicré-Gibouin, Maïté; Plésiat, Patrick; Lemanceau, Philippe; Latour, Xavier

    2015-04-01

    Pseudomonas fluorescens is commonly considered a saprophytic rhizobacterium devoid of pathogenic potential. Nevertheless, the recurrent isolation of strains from clinical human cases could indicate the emergence of novel strains originating from the rhizosphere reservoir, which could be particularly resistant to the immune system and clinical treatment. The importance of type three secretion systems (T3SSs) in the related Pseudomonas aeruginosa nosocomial species and the occurrence of this secretion system in plant-associated P. fluorescens raise the question of whether clinical isolates may also harbor T3SSs. In this study, isolates associated with clinical infections and identified in hospitals as belonging to P. fluorescens were compared with fluorescent pseudomonads harboring T3SSs isolated from plants. Bacterial isolates were tested for (i) their genetic relationships based on their 16S rRNA phylogeny, (ii) the presence of T3SS genes by PCR, and (iii) their infectious potential on animals and plants under environmental or physiological temperature conditions. Two groups of bacteria were delineated among the clinical isolates. The first group encompassed thermotolerant (41°C) isolates from patients suffering from blood infections; these isolates were finally found to not belong to P. fluorescens but were closely related and harbored highly conserved T3SS genes belonging to the Ysc-T3SS family, like the T3SSs from P. aeruginosa. The second group encompassed isolates from patients suffering from cystic fibrosis; these isolates belonged to P. fluorescens and harbored T3SS genes belonging to the Hrp1-T3SS family found commonly in plant-associated P. fluorescens. PMID:25636837

  14. Type III Secretion System and Virulence Markers Highlight Similarities and Differences between Human- and Plant-Associated Pseudomonads Related to Pseudomonas fluorescens and P. putida

    PubMed Central

    Mazurier, Sylvie; Merieau, Annabelle; Bergeau, Dorian; Decoin, Victorien; Sperandio, Daniel; Crépin, Alexandre; Barbey, Corinne; Jeannot, Katy; Vicré-Gibouin, Maïté; Plésiat, Patrick

    2015-01-01

    Pseudomonas fluorescens is commonly considered a saprophytic rhizobacterium devoid of pathogenic potential. Nevertheless, the recurrent isolation of strains from clinical human cases could indicate the emergence of novel strains originating from the rhizosphere reservoir, which could be particularly resistant to the immune system and clinical treatment. The importance of type three secretion systems (T3SSs) in the related Pseudomonas aeruginosa nosocomial species and the occurrence of this secretion system in plant-associated P. fluorescens raise the question of whether clinical isolates may also harbor T3SSs. In this study, isolates associated with clinical infections and identified in hospitals as belonging to P. fluorescens were compared with fluorescent pseudomonads harboring T3SSs isolated from plants. Bacterial isolates were tested for (i) their genetic relationships based on their 16S rRNA phylogeny, (ii) the presence of T3SS genes by PCR, and (iii) their infectious potential on animals and plants under environmental or physiological temperature conditions. Two groups of bacteria were delineated among the clinical isolates. The first group encompassed thermotolerant (41°C) isolates from patients suffering from blood infections; these isolates were finally found to not belong to P. fluorescens but were closely related and harbored highly conserved T3SS genes belonging to the Ysc-T3SS family, like the T3SSs from P. aeruginosa. The second group encompassed isolates from patients suffering from cystic fibrosis; these isolates belonged to P. fluorescens and harbored T3SS genes belonging to the Hrp1-T3SS family found commonly in plant-associated P. fluorescens. PMID:25636837

  15. Effects of Pseudomonas aureofaciens 63-28 on defense responses in soybean plants infected by Rhizoctonia solani.

    PubMed

    Jung, Woo-Jin; Park, Ro-Dong; Mabood, Fazli; Souleimanov, Alfred; L Smith, Donald

    2011-04-01

    The objective of this work was to investigate the ability of the plant growth-promoting rhizobacterium Pseudomonas aureofaciens 63-28 to induce plant defense systems, including defense-related enzyme levels and expression of defense-related isoenzymes, and isoflavone production, leading to improved resistance to the phytopathogen Rhizoctonia solani AG-4 in soybean seedlings. Seven-dayold soybean seedlings were inoculated with P. aureofaciens 63-28, R. solani AG-4, or P. aureofaciens 63-28 plus R. solani AG-4 (P+R), or not inoculated (control). After 7 days of incubation, roots treated with R. solani AG-4 had obvious damping-off symptoms, but P+R-treated soybean plants had less disease development, indicating suppression of R. solani AG-4 in soybean seedlings. Superoxide dismutase (SOD) and catalase (CAT) activities of R. solani AG-4-treated roots increased by 24.6% and 54.0%, respectively, compared with control roots. Ascorbate peroxidase (APX) and phenylalanine ammonia lyase (PAL) activities of R. solani AG-4-treated roots were increased by 75.1% and 23.6%, respectively. Polyphenol oxidase (PPO) activity in soybean roots challenged with P. aureofaciens 63-28 and P+R increased by 25.0% and 11.6%, respectively. Mn-SOD (S1 band on gel) and Fe-SOD (S2) were strongly induced in P+R-treated roots, whereas one CAT (C1) and one APX (A3) were strongly induced in R. solani AG-4- treated roots. The total isoflavone concentration in P+Rtreated shoots was 27.2% greater than the control treatment. The isoflavone yield of R. solani AG-4-treated shoots was 60.9% less than the control.

  16. Electrostatic Separator for Beneficiation of Lunar Soil

    NASA Technical Reports Server (NTRS)

    Quinn, Jacqueline; Arens, Ellen; Trigwell, Steve; Captain, James

    2010-01-01

    A charge separator has been constructed for use in a lunar environment that will allow for separation of minerals from lunar soil. In the present experiments, whole lunar dust as received was used. The approach taken here was that beneficiation of ores into an industrial feedstock grade may be more efficient. Refinement or enrichment of specific minerals in the soil before it is chemically processed may be more desirable as it would reduce the size and energy requirements necessary to produce the virgin material, and it may significantly reduce the process complexity. The principle is that minerals of different composition and work function will charge differently when tribocharged against different materials, and hence be separated in an electric field.

  17. Process for magnetic beneficiating petroleum cracking catalyst

    DOEpatents

    Doctor, R.D.

    1993-10-05

    A process is described for beneficiating a particulate zeolite petroleum cracking catalyst having metal values in excess of 1000 ppm nickel equivalents. The particulate catalyst is passed through a magnetic field in the range of from about 2 Tesla to about 5 Tesla generated by a superconducting quadrupole open-gradient magnetic system for a time sufficient to effect separation of said catalyst into a plurality of zones having different nickel equivalent concentrations. A first zone has nickel equivalents of about 6,000 ppm and greater, a second zone has nickel equivalents in the range of from about 2000 ppm to about 6000 ppm, and a third zone has nickel equivalents of about 2000 ppm and less. The zones of catalyst are separated and the second zone material is recycled to a fluidized bed of zeolite petroleum cracking catalyst. The low nickel equivalent zone is treated while the high nickel equivalent zone is discarded. 1 figures.

  18. Process for magnetic beneficiating petroleum cracking catalyst

    DOEpatents

    Doctor, Richard D.

    1993-01-01

    A process for beneficiating a particulate zeolite petroleum cracking catalyst having metal values in excess of 1000 ppm nickel equivalents. The particulate catalyst is passed through a magnetic field in the range of from about 2 Tesla to about 5 Tesla generated by a superconducting quadrupole open-gradient magnetic system for a time sufficient to effect separation of said catalyst into a plurality of zones having different nickel equivalent concentrations. A first zone has nickel equivalents of about 6,000 ppm and greater, a second zone has nickel equivalents in the range of from about 2000 ppm to about 6000 ppm, and a third zone has nickel equivalents of about 2000 ppm and less. The zones of catalyst are separated and the second zone material is recycled to a fluidized bed of zeolite petroleum cracking catalyst. The low nickel equivalent zone is treated while the high nickel equivalent zone is discarded.

  19. DECONTAMINATION AND BENEFICIAL USE OF DREDGED MATERIALS.

    SciTech Connect

    STERN, E.A.; LODGE, J.; JONES, K.W.; CLESCERI, N.L.; FENG, H.; DOUGLAS, W.S.

    2000-12-03

    Our group is leading a large-sale demonstration of dredged material decontamination technologies for the New York/New Jersey Harbor. The goal of the project is to assemble a complete system for economic transformation of contaminated dredged material into an environmentally-benign material used in the manufacture of a variety of beneficial use products. This requires the integration of scientific, engineering, business, and policy issues on matters that include basic knowledge of sediment properties, contaminant distribution visualization, sediment toxicity, dredging and dewatering techniques, decontamination technologies, and product manufacturing technologies and marketing. A summary of the present status of the system demonstrations including the use of both existing and new manufacturing facilities is given here. These decontamination systems should serve as a model for use in dredged material management plans of regions other than NY/NJ Harbor, such as Long Island Sound, where new approaches to the handling of contaminated sediments are desirable.

  20. Beneficial use of sludge in building components

    SciTech Connect

    Alleman, J.E.

    1983-12-01

    Results are presented of a study in which sludge was introduced in the manufacture of brick. More than 300 bench-scale, sludge-amended bricks were produced with initial volumetric sludge additions of from 16% to 50%. These specimens looked, felt, and smelled like standard bricks, and those with sludge additions of 30% or less were found capable of meeting the appropriate technical standards. Three full-scale runs have been completed by a commercial manufacturer, and almost one million bricks have been produced. These bricks were found comparable to normal, unadulterated bricks; in fact, the incorporation of sludge was believed to be beneficial due to related improvements in the brick's water absorption properties. The name 'biobrick' is used to refer to the new product.

  1. Biosolids management: Beneficial use comes of age

    SciTech Connect

    Hodson, C.O.

    1996-12-01

    The most important issues facing the biosolids management industry today are costs, odors and public perception. Of these, public perception has the biggest effect on the industry -- in the way biosolids are generated, used, destroyed, transported and reused. Even in the way they have been named. Officially, sludge is a term affixed to the product that comes out of sewage treatment plants and biosolids is what the processed end product is called. Although it sounds like two different things, the terms are used interchangeably. Still called sludge by some environmental professionals in the water and wastewater industries, biosolids is the official term for sludge being marketed to the public. And apparently it`s working. After years of public misperceptions, biosolids education and public relations programs thrust the organics into the Age of Beneficial Use.

  2. Produced Water Management and Beneficial Use

    SciTech Connect

    Terry Brown; Carol Frost; Thomas Hayes; Leo Heath; Drew Johnson; David Lopez; Demian Saffer; Michael Urynowicz; John Wheaton; Mark Zoback

    2007-10-31

    Large quantities of water are associated with the production of coalbed methane (CBM) in the Powder River Basin (PRB) of Wyoming. The chemistry of co-produced water often makes it unsuitable for subsequent uses such as irrigated agriculture. However, co-produced waters have substantial potential for a variety of beneficial uses. Achieving this potential requires the development of appropriate water management strategies. There are several unique characteristics of co-produced water that make development of such management strategies a challenge. The production of CBM water follows an inverse pattern compared to traditional wells. CBM wells need to maintain low reservoir pressures to promote gas production. This need renders the reinjection of co-produced waters counterproductive. The unique water chemistry of co-produced water can reduce soil permeability, making surface disposal difficult. Unlike traditional petroleum operations where co-produced water is an undesirable by-product, co-produced water in the PRB often is potable, making it a highly valued resource in arid western states. This research project developed and evaluated a number of water management options potentially available to CBM operators. These options, which focus on cost-effective and environmentally-sound practices, fall into five topic areas: Minimization of Produced Water, Surface Disposal, Beneficial Use, Disposal by Injection and Water Treatment. The research project was managed by the Colorado Energy Research Institute (CERI) at the Colorado School of Mines (CSM) and involved personnel located at CERI, CSM, Stanford University, Pennsylvania State University, the University of Wyoming, the Argonne National Laboratory, the Gas Technology Institute, the Montana Bureau of Mining and Geology and PVES Inc., a private firm.

  3. Quantitative mineralogical characterization of chrome ore beneficiation plant tailing and its beneficiated products

    NASA Astrophysics Data System (ADS)

    Das, S. K.

    2015-04-01

    Mineralogical characterization and liberation of valuable minerals are primary concerns in mineral processing industries. The present investigation focuses on quantitative mineralogy, elemental deportment, and locking-liberation characteristics of the beneficiation of tailings from a chrome ore beneficiation plant in the Sukinda region, Odisha; methods used for the study of the beneficiated tailings are QEMSCAN®, X-ray diffraction (XRD), and mineral chemistry by a scanning electron microscope equipped with an energy-dispersive spectrometer (SEM-EDS). The tailing sample was fine grained (69.48wt% below 45 μm size), containing 20.25wt% Cr2O3 and 39.19wt% Fe2O3, with a Cr:Fe mass ratio of 0.51. Mineralogical investigations using QEMSCAN studies revealed that chromite, goethite, and gibbsite are the dominant mineral phases with minor amounts of hematite, kaolinite, and quartz. The sample contained 34.22wt% chromite, and chromite liberation is more than 80% for grains smaller than 250 μm in size. Based on these results, it was predicted that liberated chromite and high-grade middling chromite particles could be separated from the gangue by various concentration techniques. The tailing sample was beneficiated by hydrocyclone, tabling, wet high-intensity magnetic separation (WHIMS), and flotation in order to recover the chromite. A chromite concentrate with 45.29wt% Cr2O3 and a Cr:Fe mass ratio of 1.85 can be produced from these low-grade chromite ore beneficiation plant rejects.

  4. Phylogenomics and systematics in Pseudomonas

    PubMed Central

    Gomila, Margarita; Peña, Arantxa; Mulet, Magdalena; Lalucat, Jorge; García-Valdés, Elena

    2015-01-01

    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. PMID:26074881

  5. Chromium reduction in Pseudomonas putida.

    PubMed Central

    Ishibashi, Y; Cervantes, C; Silver, S

    1990-01-01

    Reduction of hexavalent chromium (chromate) to less-toxic trivalent chromium was studied by using cell suspensions and cell-free supernatant fluids from Pseudomonas putida PRS2000. Chromate reductase activity was associated with soluble protein and not with the membrane fraction. The crude enzyme activity was heat labile and showed a Km of 40 microM CrO4(2-). Neither sulfate nor nitrate affected chromate reduction either in vitro or with intact cells. PMID:2389940

  6. Pseudomonas blight discovered on raspberry in Watsonville

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In the winter (February) of 2013, a field of raspberries in Watsonville was discovered to be infected with Pseudomonas syringae, the causal agent of Pseudomonas blight disease. This was the first documentation of this disease on raspberry in our region. The infection of raspberry plants is manifeste...

  7. Bromoalkane-degrading Pseudomonas strains

    SciTech Connect

    Shochat, E.; Hermoni, I.; Cohen, Z.; Abeliovich, A.; Belkin, S. )

    1993-05-01

    Many of the xenobiotic compounds extensively used in agriculture and industry, particularly the chlorinated halogenated compounds, have been extensively studied. Brominated organics, also used worldwide in, for example, flame retardants, pesticides, industrial biocides, intermediates in the polymer industry, have received far less attention. Investigations into the biodegradative pathways of aliphatic bromides in particular is very limited. This paper reports the isolation and preliminary characterization of two Pseudomonas strains capable of utilizing a broad range of bromoalkanes as single carbon and energy sources, and describes the emulsification and dehalogenation of hydrophobic bromoakanes by these strains. 37 refs., 6 figs., 2 tabs.

  8. Pseudomonas--an opportunistic foe.

    PubMed

    Baillie, Jonathan

    2014-01-01

    An honest account of some of the lessons learned in how to protect patients, staff, and visitors, against waterborne Pseudomonas aeruginosa by effectively monitoring a large healthcare facility's water supply, identifying potential 'trigger points', harnessing the expertise of a multidisciplinary team, encouraging all staff to 'go the extra mile' preventatively, and above all, 'going beyond compliance', was provided by George McCracken, head of Estates Risk and Environment at the Belfast Health and Social Care Trust--in whose Royal Jubilee Maternity Hospital three young babies died after an outbreak of the bacteraemia in early 2012--at a recent Water Management Society conference. HEJ editor, Jonathan Baillie, reports. PMID:24516937

  9. Ferrofluid effect on Pseudomonas pyoverdine

    NASA Astrophysics Data System (ADS)

    Poiata, Antoniea; Vlahovici, Al.; Creanga, Dorina-Emilia

    2005-03-01

    The magnetic fluid effect on some pigmented pathogen germs has been investigated. The fluorescence of the pyoverdine pigment obtained from Pseudomonas aeruginosa strain, cultivated in the presence of different magnetic fluid concentrations, was enhanced by magnetic fluid concentrations of 0.0015-1 ml/l. The antimicrobial activity of pyoverdine, when tested by means of agar diffusimetric method against Sarcina lutea, was found increased for relatively high concentrations of magnetic fluid; in the case of Staphylococcus aureus the pyoverdine antimicrobial activity was not dependent on the magnetic fluid concentration.

  10. Various effects of fluorescent bacteria of the genus Pseudomonas containing ACC deaminase on wheat seedling growth.

    PubMed

    Magnucka, Elżbieta G; Pietr, Stanisław J

    2015-12-01

    The study evaluates the effect of rhizobacteria having 1-aminocyclopropane-1-carboxylate deaminase (ACCd) on the development of wheat seedlings. This enzyme has been proposed to play a key role in microbe-plant association. Three fluorescent pseudomonads containing this deaminase were selected from 70 strains of pseudomonads isolated from rhizosphere of wheat (Triticum aestivum L.) and rape (Brassica napus L.). These bacteria, varied significantly in the ability to both biosynthesize auxins and hydrolyze ACC. Among them, Pseudomonas brassicacearum subsp. brassicacearum strain RZ310 presented the highest activities of ACC deaminase during 96h of growth in liquid Dworkin and Foster (DF) salt medium. Additionally, this rape rhizosphere strain did not produce indoles. Two other isolates, Pseudomonas sp. PO283 and Pseudomonas sp. PO366, secreted auxins only in the presence of their precursor. Phylogenetic analysis of the 16S rRNA gene and four other protein-encoding genes indicated that these wheat rhizosphere isolates belonged to the fluorescent Pseudomonas group. Moreover, the effects of these strains on wheat seedling growth under in vitro conditions were markedly dependent on both their cell suspensions used to grain inoculation and nutrient conditions. Strains tested had beneficial influence on wheat seedlings mainly at low cell densities. In addition, access to nutrients markedly changed bacteria action on cereal growth. Their presence generally favored the positive effects of pseudomonads on length and the estimated biomasses of wheat coleoptiles. Despite these general rules, impacts of each isolate on the growth parameters of cereal seedlings were unique. PMID:25983132

  11. Various effects of fluorescent bacteria of the genus Pseudomonas containing ACC deaminase on wheat seedling growth.

    PubMed

    Magnucka, Elżbieta G; Pietr, Stanisław J

    2015-12-01

    The study evaluates the effect of rhizobacteria having 1-aminocyclopropane-1-carboxylate deaminase (ACCd) on the development of wheat seedlings. This enzyme has been proposed to play a key role in microbe-plant association. Three fluorescent pseudomonads containing this deaminase were selected from 70 strains of pseudomonads isolated from rhizosphere of wheat (Triticum aestivum L.) and rape (Brassica napus L.). These bacteria, varied significantly in the ability to both biosynthesize auxins and hydrolyze ACC. Among them, Pseudomonas brassicacearum subsp. brassicacearum strain RZ310 presented the highest activities of ACC deaminase during 96h of growth in liquid Dworkin and Foster (DF) salt medium. Additionally, this rape rhizosphere strain did not produce indoles. Two other isolates, Pseudomonas sp. PO283 and Pseudomonas sp. PO366, secreted auxins only in the presence of their precursor. Phylogenetic analysis of the 16S rRNA gene and four other protein-encoding genes indicated that these wheat rhizosphere isolates belonged to the fluorescent Pseudomonas group. Moreover, the effects of these strains on wheat seedling growth under in vitro conditions were markedly dependent on both their cell suspensions used to grain inoculation and nutrient conditions. Strains tested had beneficial influence on wheat seedlings mainly at low cell densities. In addition, access to nutrients markedly changed bacteria action on cereal growth. Their presence generally favored the positive effects of pseudomonads on length and the estimated biomasses of wheat coleoptiles. Despite these general rules, impacts of each isolate on the growth parameters of cereal seedlings were unique.

  12. Beneficial Reuse of San Ardo Produced Water

    SciTech Connect

    Robert A. Liske

    2006-07-31

    This DOE funded study was performed to evaluate the potential for treatment and beneficial reuse of produced water from the San Ardo oilfield in Monterey County, CA. The potential benefits of a successful full-scale implementation of this project include improvements in oil production efficiency and additional recoverable oil reserves as well as the addition of a new reclaimed water resource. The overall project was conducted in two Phases. Phase I identified and evaluated potential end uses for the treated produced water, established treated water quality objectives, reviewed regulations related to treatment, transport, storage and use of the treated produced water, and investigated various water treatment technology options. Phase II involved the construction and operation of a small-scale water treatment pilot facility to evaluate the process's performance on produced water from the San Ardo oilfield. Cost estimates for a potential full-scale facility were also developed. Potential end uses identified for the treated water include (1) agricultural use near the oilfield, (2) use by Monterey County Water Resources Agency (MCWRA) for the Salinas Valley Water Project or Castroville Seawater Intrusion Project, (3) industrial or power plant use in King City, and (4) use for wetlands creation in the Salinas Basin. All of these uses were found to have major obstacles that prevent full-scale implementation. An additional option for potential reuse of the treated produced water was subsequently identified. That option involves using the treated produced water to recharge groundwater in the vicinity of the oil field. The recharge option may avoid the limitations that the other reuse options face. The water treatment pilot process utilized: (1) warm precipitation softening to remove hardness and silica, (2) evaporative cooling to meet downstream temperature limitations and facilitate removal of ammonia, and (3) reverse osmosis (RO) for removal of dissolved salts, boron, and

  13. Beneficiation of ilmenite from lumar analog

    NASA Technical Reports Server (NTRS)

    Ramadorai, G.; Dean, R.

    1992-01-01

    must be emphasized that improved grades and recoveries can be obtained with the -400 mesh fines. However, beneficiation of these extremely fine materials is not possible in a practical process scheme.

  14. Maize heterosis affects the structure and dynamics of indigenous rhizospheric auxins-producing Pseudomonas populations.

    PubMed

    Picard, Christine; Bosco, Marco

    2005-08-01

    A rhizobacterial population of 2430 Pseudomonas isolates, originating from one maize hybrid and from its parents, was screened for auxins production. Four hundred and twelve isolates were found to be auxin producers (aia+), and 27 of them were also part of a previously described PhlD+ sub-population. Interestingly, most part of the aia(+)-PhlD+ isolates came from the hybrid. This finding indicates that heterosis allows an increased colonisation by multi-beneficial PGPR strains. Furthermore, results on the abundance and genetic diversity of aia+ isolates gave evidence that maize root colonisation by aia+ Pseudomonas is an inherited trait regulated by heterosis. In fact, two times more aia+ isolates were obtained from the rhizosphere of the hybrid than from the rhizospheres of the parents, and an amplified rDNA restriction analysis showed that the hybrid increases the genetic diversity of aia+ populations when compared to its parents. PMID:16329954

  15. Different responses of pyoverdine genes to autoinduction in Pseudomonas aeruginosa and the group Pseudomonas fluorescens-Pseudomonas putida.

    PubMed

    Ambrosi, Cecilia; Leoni, Livia; Visca, Paolo

    2002-08-01

    We investigated the regulation of the psbA and pvdA pyoverdine biosynthesis genes, which encode the L-ornithine N(5)-oxygenase homologues in Pseudomonas strain B10 and Pseudomonas aeruginosa PAO1, respectively. We demonstrate that pyoverdine(B10), as the end product of its biosynthetic pathway, is a key participant of the control circuit regulating its own production in Pseudomonas strain B10. In P. aeruginosa PAO1, however, pyoverdine(PAO1) has no apparent role in the positive regulation of the pvdA gene. PMID:12147517

  16. Beneficiation-hydroretort processing of US oil shales, engineering study

    SciTech Connect

    Johnson, L.R.; Riley, R.H.

    1988-12-01

    This report describes a beneficiation facility designed to process 1620 tons per day of run-of-mine Alabama oil shale containing 12.7 gallons of kerogen per ton of ore (based on Fischer Assay). The beneficiation facility will produce briquettes of oil shale concentrate containing 34.1 gallons of kerogen per ton (based on Fischer Assay). The beneficiation facility will produce briquettes of oil shale concentrate containing 34.1 gallons of kerogen per ton (based on Fischer Assay) suitable for feed to a hydroretort oil extraction facility of nominally 20,000 barrels per day capacity. The beneficiation plant design prepared includes the operations of crushing, grinding, flotation, thickening, filtering, drying, briquetting, conveying and tailings empoundment. A complete oil shale beneficiation plant is described including all anticipated ancillary facilities. For purposes of determining capital and operating costs, the beneficiation facility is assumed to be located on a generic site in the state of Alabama. The facility is described in terms of the individual unit operations with the capital costs being itemized in a similar manner. Additionally, the beneficiation facility estimated operating costs are presented to show operating costs per ton of concentrate produced, cost per barrel of oil contained in concentrate and beneficiation cost per barrel of oil extracted from concentrate by hydroretorting. All costs are presented in fourth quarter of 1988 dollars.

  17. Growth of genetically engineered Pseudomonas aeruginosa and Pseudomonas putida in soil and rhizosphere.

    PubMed Central

    Yeung, K H; Schell, M A; Hartel, P G

    1989-01-01

    The effect of the addition of a recombinant plasmid containing the pglA gene encoding an alpha-1,4-endopolygalacturonase from Pseudomonas solanacearum on the growth of Pseudomonas aeruginosa and Pseudomonas putida in soil and rhizosphere was determined. Despite a high level of polygalacturonase production by genetically engineered P. putida and P. aeruginosa, the results suggest that polygalacturonase production had little effect on the growth of these strains in soil or rhizosphere. PMID:2515805

  18. Siderophore production by Pseudomonas pseudomallei.

    PubMed Central

    Yang, H M; Chaowagul, W; Sokol, P A

    1991-01-01

    Eighty-four strains of Pseudomonas pseudomallei isolated from patients with melioidosis were examined for siderophore production. All the strains were shown to produce siderophore both on chrome azurol S agar plates and in liquid medium under iron-deficient conditions. Chemical assays indicated that the siderophore belongs to the hydroxamate class. Addition of iron to the culture medium resulted in increased culture growth with markedly decreased yield of siderophore. Siderophore produced by strain U7 was purified by gel filtration chromatography, and the molecular weight was estimated to be 1,000. When this partially purified siderophore was added to culture medium, it promoted iron uptake by P. pseudomallei in the presence of EDTA and enhanced growth of the organism in the presence of transferrin. We have given this siderophore the trivial name malleobactin. PMID:1825486

  19. Formation of isoamylase by Pseudomonas.

    PubMed

    Harada, T; Yokobayashi, K; Misaki, A

    1968-10-01

    We have isolated a Pseudomonas sp. (strain SB15) which produces an isoamylase (EC 3.2.1.9). Highest yields of this enzyme were obtained when the bacterium was grown in shaken culture in a medium containing maltose, dextrin, starch, or isomaltose. Specific carbon and nitrogen sources were required for growth. The most satisfactory medium consisted of 2% maltose, 0.4% sodium glutamate, 0.3% diammonium hydrogen phosphate, and other inorganic salts. The optimal pH for enzyme production was 5 to 6. The enzyme is stable between pH 3 and 6 but is extremely labile above pH 7. It splits amylopectin completely by combined action with beta-amylase but does not attack pullulan. PMID:5684197

  20. Formate dehydrogenase from Pseudomonas oxalaticus.

    PubMed

    Müller, U; Willnow, P; Ruschig, U; Höpner, T

    1978-02-01

    Formate dehydrogenase (EC 1.2.1.2) from Pseudomonas oxalaticus has been isolated and characterized. The enzyme (molecular weight 315000) is a complex flavoprotein containing 2 FMN, 18--25 non-heme iron atoms and 15--20 acid-labile sulphides. In the last step of the purification, a sucrose gradient centrifugation, a second catalytically active species has been found apparently originating from a dissociation of the enzyme into two equal subunits. The enzyme is specific toward its natural substrate formate. It transfers electrons to NAD+, oxygen, ferricyanide, and a lot of nonphysiological acceptors (dyes). In addition electrons are transferred from NADH to these acceptors. The (reversible) removal of FMN requires a reduction step. Reincorporation has been followed by the reappearance of the reactivity against formate and by fluorescence titration. The deflavo enzyme also binds FAD and riboflavin. The resulting enzyme species show characteristic catalytic abilities. Activity against formate is peculiar to the FMN species. PMID:631130

  1. Glyphosate catabolism by Pseudomonas sp

    SciTech Connect

    Shinabarger, D.L.

    1986-01-01

    The pathway for the degradation of glyphosate (N-phosphonomethylglycine) by Pseudomonas sp. PG2982 has been determined using metabolic radiolabeling experiments. Radiorespirometry experiments utilizing (3-/sup 14/C) glyphosate revealed that approximately 50-59% of the C3 carbon was oxidized to CO/sub 2/. Fractionation of stationary phase cells labeled with (3-/sup 14/C)glyphosate revealed that from 45-47% of the assimilated C3 carbon is distributed to proteins and that amino acids methionine and serine are highly labeled. The nucleic acid bases adenine and guanine received 90% of the C3 label that was incorporated into nucleic acids, and the only pyrimidine base labeled was thymine. Pulse labeling of PG2982 cells with (3-/sup 14/C)glyphosate revealed that (3-/sup 14/C)sarcosine is an intermediate in glyphosate degradation. Examination of crude extracts prepared from PG2982 cells revealed the presence of an enzyme that oxidizes sarcosine to glycine and formaldehyde. These results indicate that the first step in glyphosate degradation by PG2982 is cleavage of the carbon-phosphorus bond, resulting in the release of sarcosine and a phosphate group. The phosphate group is utilized as a source of phosphorus, and the sarcosine is degraded to glycine and formaldehyde. Phosphonate utilization by Pseudomonas sp. PG2982 was investigated. Each of the ten phosphonates tested were utilized as a sole source of phosphorus by PG2982. Representative compounds tested included alkylphosphonates, 1-amino-substituted alkylphosphonates, amino-terminal phosphonates, and an arylphosphonate. PG2982 cultures degraded phenylphosphonate to benzene and produced methane from methylphosphonate. The data indicate that PG2982 is capable of cleaving the carbon-phosphorus bond of several structurally different phosphonates.

  2. Antibiotic Conditioned Growth Medium of Pseudomonas Aeruginosa

    ERIC Educational Resources Information Center

    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.

  3. Genome sequence reveals that Pseudomonas fluorescens F113 possesses a large and diverse array of systems for rhizosphere function and host interaction

    PubMed Central

    2013-01-01

    Background Pseudomonas fluorescens F113 is a plant growth-promoting rhizobacterium (PGPR) isolated from the sugar-beet rhizosphere. This bacterium has been extensively studied as a model strain for genetic regulation of secondary metabolite production in P. fluorescens, as a candidate biocontrol agent against phytopathogens, and as a heterologous host for expression of genes with biotechnological application. The F113 genome sequence and annotation has been recently reported. Results Comparative analysis of 50 genome sequences of strains belonging to the P. fluorescens group has revealed the existence of five distinct subgroups. F113 belongs to subgroup I, which is mostly composed of strains classified as P. brassicacearum. The core genome of these five strains is highly conserved and represents approximately 76% of the protein-coding genes in any given genome. Despite this strong conservation, F113 also contains a large number of unique protein-coding genes that encode traits potentially involved in the rhizocompetence of this strain. These features include protein coding genes required for denitrification, diterpenoids catabolism, motility and chemotaxis, protein secretion and production of antimicrobial compounds and insect toxins. Conclusions The genome of P. fluorescens F113 is composed of numerous protein-coding genes, not usually found together in previously sequenced genomes, which are potentially decisive during the colonisation of the rhizosphere and/or interaction with other soil organisms. This includes genes encoding proteins involved in the production of a second flagellar apparatus, the use of abietic acid as a growth substrate, the complete denitrification pathway, the possible production of a macrolide antibiotic and the assembly of multiple protein secretion systems. PMID:23350846

  4. OXIDATION OF POLYCHLORINATED BIPHENYLS BY PSEUDOMONAS SP. STRAIN LB400 AND PSEUDOMONAS PSEUDOALCALIGENES KF707

    EPA Science Inventory

    Biphenyl-grown cells and cell extracts prepared from biphenyl-grown cells of Pseudomonas sp. strain LB400 oxidize a much wider range of chlorinated biphenyls than do analogous preparations from Pseudomonas pseudoalcaligenes KF707. These results are attributed to differences in th...

  5. Oxidation of polychlorinated biphenyls by pseudomonas sp. strain LB400 and pseudomonas pseudoalcaligenes KF707

    SciTech Connect

    Gibson, D.T.; Cruden, D.L.; Haddock, J.D.; Zylstra, G.J.; Brand, J.M.

    1993-01-01

    Biphenyl-grown cells and cell extracts prepared from biphenyl-grown cells of Pseudomonas sp. strain LB400 oxidize a much wider range of chlorinated biphenyls that do analogous preparations from Pseudomonas pseudoalcaligenes KF707. These results are attributed to differences in the substrate specificity of the biphenyl 2,3-dioxygenases from both organisms.

  6. Acceptance for Beneficial Use Pumping Instrumentation and Control Skid P

    SciTech Connect

    KOCH, M.R.

    2000-04-19

    This Acceptance for Beneficial Use documents that Pumping Instrumentation and Control (PIC) skid ''P'' is ready for field use. This document does not cover the field installation or operational testing.

  7. Beneficial Fitness Effects Are Not Exponential for Two Viruses

    PubMed Central

    Rokyta, Darin R.; Beisel, Craig J.; Joyce, Paul; Ferris, Martin T.; Burch, Christina L.; Wichman, Holly A.

    2008-01-01

    The distribution of fitness effects for beneficial mutations is of paramount importance in determining the outcome of adaptation. It is generally assumed that fitness effects of beneficial mutations follow an exponential distribution, for example, in theoretical treatments of quantitative genetics, clonal interference, experimental evolution, and the adaptation of DNA sequences. This assumption has been justified by the statistical theory of extreme values, because the fitnesses conferred by beneficial mutations should represent samples from the extreme right tail of the fitness distribution. Yet in extreme value theory, there are three different limiting forms for right tails of distributions, and the exponential describes only those of distributions in the Gumbel domain of attraction. Using beneficial mutations from two viruses, we show for the first time that the Gumbel domain can be rejected in favor of a distribution with a right-truncated tail, thus providing evidence for an upper bound on fitness effects. Our data also violate the common assumption that small-effect beneficial mutations greatly outnumber those of large effect, as they are consistent with a uniform distribution of beneficial effects. PMID:18779988

  8. Composition of Pseudomonas aeruginosa slime

    PubMed Central

    Brown, M. R. W.; Foster, J. H. Scott; Clamp, J. R.

    1969-01-01

    1. The slime produced by eight strains of Pseudomonas aeruginosa on a number of different media was demonstrated to be qualitatively the same. Small quantitative differences may be occasioned by differences in the extraction procedure, the growth medium or the strain of organism used. 2. The slime was shown to be predominantly polysaccharide with some nucleic acid material and a small amount of protein. 3. The hydrolysed polysaccharide fraction consists mainly of glucose with smaller amounts of mannose. This accounts for some 50–60% of the total slime. In addition, there is some 5% of hyaluronic acid. The nucleic acid material represents approx. 20% of the total weight, and is composed of both RNA and DNA. 4. Minor components are protein, rhamnose and glucosamine, the protein being less than 5% of the total. 5. Hyaluronic acid is produced in greater quantities from nutrient broth than from chemically defined media, and is more firmly attached to the cells than the other components. PMID:4240755

  9. Silver against Pseudomonas aeruginosa biofilms.

    PubMed

    Bjarnsholt, Thomas; Kirketerp-Møller, Klaus; Kristiansen, Søren; Phipps, Richard; Nielsen, Anne Kirstine; Jensen, Peter Østrup; Høiby, Niels; Givskov, Michael

    2007-08-01

    Silver has been recognized for its antimicrobial properties for centuries. Most studies on the antibacterial efficacy of silver, with particular emphasis on wound healing, have been performed on planktonic bacteria. Our recent studies, however, strongly suggest that colonization of wounds involves 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, but that the silver concentration is important. A concentration of 5-10 mug/mL silver sulfadiazine eradicated the biofilm whereas a lower concentration (1 mug/mL) had no effect. The bactericidal concentration of silver required to eradicate the bacterial biofilm was 10-100 times higher than that used to eradicate planktonic bacteria. These observations strongly indicate that the concentration of silver in currently available wound dressings is much too low for treatment of chronic biofilm wounds. It is suggested that clinicians and manufacturers of the said wound dressings consider whether they are treating wounds primarily colonized either by biofilm-forming or planktonic bacteria.

  10. Beneficial consequences of a selective glutamine synthetase inhibitor in oats and legumes

    SciTech Connect

    Langston-Unkefer, P.J.; Knight, T.J.; Sengupta-Gopalan, C.

    1988-01-01

    We report on the effects of administering a unique glutamine synthetase inhibitor to cereals and N/sub 2/-fixing legumes. A bacterium (Pseudomonas syringae pv. tabaci) delivers this inhibitor to provide extended treatment periods; we inoculated the root systems of oat and legume plants with pv. tabaci to provide for delivery of this inhibitor to their root or root/nodule systems. Inoculation of legumes is accompanied by increased plant growth, total plant nitrogen, nodulation, and nitrogen fixation activity. Inoculation of the oats is accompanied by either of two results depending upon the genotype of the oat plant. One result is inhibition of plant growth followed by plant death as consequences of the loss of all of the glutamine synthetase activities in the plant and the subsequent accumulation of ammonia and cessation of nitrate uptake. The second and opposite result is observed in a small population of oats screened from a commercial cultivar and includes increased plant growth and leaf protein. The effects of this inhibitor can be beneficial when applied to appropriate plant material. In an attempt to effectively communicate these findings to the reader, we first introduce the inhibitor (a novel amino acid) and its bacterial delivery systems, the target of the inhibitor (glutamine synthetase-catalyzed ammonia assimilation), and the two different nitrogen economics in the legume and cereal plants used experimentally. The physiological, biochemical, and molecular genetic consequences of the inhibitor action in cereals and legumes, as we presently understand them, are then presented. 18 refs., 4 figs., 3 tabs.,

  11. Enhancing plant productivity while suppressing biofilm growth in a windowfarm system using beneficial bacteria and ultraviolet irradiation.

    PubMed

    Lee, Seungjun; Ge, Chongtao; Bohrerova, Zuzana; Grewal, Parwinder S; Lee, Jiyoung

    2015-07-01

    Common problems in a windowfarm system (a vertical and indoor hydroponic system) are phytopathogen infections in plants and excessive buildup of biofilms. The objectives of this study were (i) to promote plant health by making plants more resistant to infection by using beneficial biosurfactant-producing Pseudomonas chlororaphis around the roots and (ii) to minimize biofilm buildup by ultraviolet (UV) irradiation of the water reservoir, thereby extending the lifespan of the whole system with minimal maintenance. Pseudomonas chlororaphis-treated lettuce grew significantly better than nontreated lettuce, as indicated by enhancement of color, mass, length, and number of leaves per head (p < 0.05). The death rate of the lettuce was reduced by ∼ 50% when the lettuce was treated with P. chlororaphis. UV irradiation reduced the bacteria (4 log reduction) and algae (4 log reduction) in the water reservoirs and water tubing systems. Introduction of P. chlororaphis into the system promoted plant growth and reduced damage caused by the plant pathogen Pythium ultimum. UV irradiation of the water reservoir reduced algal and biofilm growth and extended the lifespan of the system.

  12. Growth and (137)Cs uptake of four Brassica species influenced by inoculation with a plant growth-promoting rhizobacterium Bacillus pumilus in three contaminated farmlands in Fukushima prefecture, Japan.

    PubMed

    Aung, Han Phyo; Djedidi, Salem; Oo, Aung Zaw; Aye, Yi Swe; Yokoyama, Tadashi; Suzuki, Sohzoh; Sekimoto, Hitoshi; Bellingrath-Kimura, Sonoko Dorothea

    2015-07-15

    The effectiveness of the plant growth-promoting rhizobacterium Bacillus pumilus regarding growth promotion and radiocesium ((137)Cs) uptake was evaluated in four Brassica species grown on different (137)Cs contaminated farmlands at Fukushima prefecture in Japan from June to August 2012. B. pumilus inoculation did not enhance growth in any of the plants, although it resulted in a significant increase of (137)Cs concentration and higher (137)Cs transfer from the soil to plants. The Brassica species exhibited different (137)Cs uptake abilities in the order Komatsuna>turnip>mustard>radish. TF values of (137)Cs ranged from 0.018 to 0.069 for all vegetables. Komatsuna possessed the largest root surface area and root volume, and showed a higher (137)Cs concentration in plant tissue and higher (137)Cs TF values (0.060) than the other vegetables. Higher (137)Cs transfer to plants was prominent in soil with a high amount of organic matter and an Al-vermiculite clay mineral type. PMID:25847170

  13. Growth and (137)Cs uptake of four Brassica species influenced by inoculation with a plant growth-promoting rhizobacterium Bacillus pumilus in three contaminated farmlands in Fukushima prefecture, Japan.

    PubMed

    Aung, Han Phyo; Djedidi, Salem; Oo, Aung Zaw; Aye, Yi Swe; Yokoyama, Tadashi; Suzuki, Sohzoh; Sekimoto, Hitoshi; Bellingrath-Kimura, Sonoko Dorothea

    2015-07-15

    The effectiveness of the plant growth-promoting rhizobacterium Bacillus pumilus regarding growth promotion and radiocesium ((137)Cs) uptake was evaluated in four Brassica species grown on different (137)Cs contaminated farmlands at Fukushima prefecture in Japan from June to August 2012. B. pumilus inoculation did not enhance growth in any of the plants, although it resulted in a significant increase of (137)Cs concentration and higher (137)Cs transfer from the soil to plants. The Brassica species exhibited different (137)Cs uptake abilities in the order Komatsuna>turnip>mustard>radish. TF values of (137)Cs ranged from 0.018 to 0.069 for all vegetables. Komatsuna possessed the largest root surface area and root volume, and showed a higher (137)Cs concentration in plant tissue and higher (137)Cs TF values (0.060) than the other vegetables. Higher (137)Cs transfer to plants was prominent in soil with a high amount of organic matter and an Al-vermiculite clay mineral type.

  14. Induced drought tolerance through wild and mutant bacterial strain Pseudomonas simiae in mung bean (Vigna radiata L.).

    PubMed

    Kumari, Sarita; Vaishnav, Anukool; Jain, Shekhar; Varma, Ajit; Choudhary, Devendra Kumar

    2016-01-01

    The present study focused on the overproducing mutant of a plant growth promoting rhizobacterium (PGPR) Pseudomonas simiae strain AU (MTCC-12057) for significant drought tolerance in mung bean plants. Five mutants namely AU-M1, AU-M2, AU-M3, AU-M4 and AU-M5 were made after treatment of wild type strain with N-methyl-N-nitro-N-nitrosoguanidine. Mutant strain AU-M4 was recorded for enhanced ACC deaminase (ACC-D) activity, indole acetic acid (IAA) production and inorganic phosphate (Pi) solubilization compared to wild strain and other four mutant strains under drought condition. AU-M4 showed higher phosphate solubilization index (8.17) together with higher ACC-D activity (98 nmol/mg/h) and IAA concentration (69.35 µg/ml) compared with the wild type P. simiae strain AU ACC-D activity (79 nmol/mg/h) and IAA concentration (38.98 µg/ml) respectively. In this report, we investigated the effect of both wild and mutant type bacterial strain on mung bean plants under drought stress. Results showed that mutant AU-M4 and wild type strain AU inoculated plants exhibited superior tolerance against drought stress, as shown by their enhanced plant biomass (fresh weight), higher water content, higher proline accumulation and lower osmotic stress injury. Mutant AU-M4 and wild strain AU inoculated plants reduced the ethylene level by 59 and 45% respectively, compared to the control under stress condition. Furthermore, bacterial inoculated plants showed enhanced induced systemic drought tolerance by reducing stomata size and net photosynthesis resulting higher water content in mung bean plants that may help in survival of plants during drought condition. To mitigate the effects of drought stress, use of PGPR will be needed to ensure sufficient production of food from crop plants. Taking current leads available, concerted future research is needed in this area, particularly on field evaluation with application of potential microorganisms.

  15. Induced drought tolerance through wild and mutant bacterial strain Pseudomonas simiae in mung bean (Vigna radiata L.).

    PubMed

    Kumari, Sarita; Vaishnav, Anukool; Jain, Shekhar; Varma, Ajit; Choudhary, Devendra Kumar

    2016-01-01

    The present study focused on the overproducing mutant of a plant growth promoting rhizobacterium (PGPR) Pseudomonas simiae strain AU (MTCC-12057) for significant drought tolerance in mung bean plants. Five mutants namely AU-M1, AU-M2, AU-M3, AU-M4 and AU-M5 were made after treatment of wild type strain with N-methyl-N-nitro-N-nitrosoguanidine. Mutant strain AU-M4 was recorded for enhanced ACC deaminase (ACC-D) activity, indole acetic acid (IAA) production and inorganic phosphate (Pi) solubilization compared to wild strain and other four mutant strains under drought condition. AU-M4 showed higher phosphate solubilization index (8.17) together with higher ACC-D activity (98 nmol/mg/h) and IAA concentration (69.35 µg/ml) compared with the wild type P. simiae strain AU ACC-D activity (79 nmol/mg/h) and IAA concentration (38.98 µg/ml) respectively. In this report, we investigated the effect of both wild and mutant type bacterial strain on mung bean plants under drought stress. Results showed that mutant AU-M4 and wild type strain AU inoculated plants exhibited superior tolerance against drought stress, as shown by their enhanced plant biomass (fresh weight), higher water content, higher proline accumulation and lower osmotic stress injury. Mutant AU-M4 and wild strain AU inoculated plants reduced the ethylene level by 59 and 45% respectively, compared to the control under stress condition. Furthermore, bacterial inoculated plants showed enhanced induced systemic drought tolerance by reducing stomata size and net photosynthesis resulting higher water content in mung bean plants that may help in survival of plants during drought condition. To mitigate the effects of drought stress, use of PGPR will be needed to ensure sufficient production of food from crop plants. Taking current leads available, concerted future research is needed in this area, particularly on field evaluation with application of potential microorganisms. PMID:26712619

  16. Genome-based discovery, structure prediction and functional analysis of cyclic lipopeptide antibiotics in Pseudomonas species.

    PubMed

    de Bruijn, Irene; de Kock, Maarten J D; Yang, Meng; de Waard, Pieter; van Beek, Teris A; Raaijmakers, Jos M

    2007-01-01

    Analysis of microbial genome sequences have revealed numerous genes involved in antibiotic biosynthesis. In Pseudomonads, several gene clusters encoding non-ribosomal peptide synthetases (NRPSs) were predicted to be involved in the synthesis of cyclic lipopeptide (CLP) antibiotics. Most of these predictions, however, are untested and the association between genome sequence and biological function of the predicted metabolite is lacking. Here we report the genome-based identification of previously unknown CLP gene clusters in plant pathogenic Pseudomonas syringae strains B728a and DC3000 and in plant beneficial Pseudomonas fluorescens Pf0-1 and SBW25. For P. fluorescens SBW25, a model strain in studying bacterial evolution and adaptation, the structure of the CLP with a predicted 9-amino acid peptide moiety was confirmed by chemical analyses. Mutagenesis confirmed that the three identified NRPS genes are essential for CLP synthesis in strain SBW25. CLP production was shown to play a key role in motility, biofilm formation and in activity of SBW25 against zoospores of Phytophthora infestans. This is the first time that an antimicrobial metabolite is identified from strain SBW25. The results indicate that genome mining may enable the discovery of unknown gene clusters and traits that are highly relevant in the lifestyle of plant beneficial and plant pathogenic bacteria.

  17. Pseudomonas aeruginosa biofilms in disease.

    PubMed

    Mulcahy, Lawrence R; Isabella, Vincent M; Lewis, Kim

    2014-07-01

    Pseudomonas aeruginosa is a ubiquitous organism that is the focus of intense research because of its prominent role in disease. Due to its relatively large genome and flexible metabolic capabilities, this organism exploits numerous environmental niches. It is an opportunistic pathogen that sets upon the human host when the normal immune defenses are disabled. Its deadliness is most apparent in cystic fibrosis patients, but it also is a major problem in burn wounds, chronic wounds, chronic obstructive pulmonary disorder, surface growth on implanted biomaterials, and within hospital surface and water supplies, where it poses a host of threats to vulnerable patients (Peleg and Hooper, N Engl J Med 362:1804-1813, 2010; Breathnach et al., J Hosp Infect 82:19-24, 2012). Once established in the patient, P. aeruginosa can be especially difficult to treat. The genome encodes a host of resistance genes, including multidrug efflux pumps (Poole, J Mol Microbiol Biotechnol 3:255-264, 2001) and enzymes conferring resistance to beta-lactam and aminoglycoside antibotics (Vahdani et al., Annal Burns Fire Disast 25:78-81, 2012), making therapy against this gram-negative pathogen particularly challenging due to the lack of novel antimicrobial therapeutics (Lewis, Nature 485: 439-440, 2012). This challenge is compounded by the ability of P. aeruginosa to grow in a biofilm, which may enhance its ability to cause infections by protecting bacteria from host defenses and chemotherapy. Here, we review recent studies of P. aeruginosa biofilms with a focus on how this unique mode of growth contributes to its ability to cause recalcitrant infections.

  18. New naphthalene-degrading marine Pseudomonas strains

    SciTech Connect

    Garcia-Valdes, E.; Cozar, E.; Rotger, R. Lalucat, J. ); Ursing, J. )

    1988-10-01

    Over 100 strains that utilized naphthalene as the only carbon and energy source were isolated from samples of marine sediments taken from a heavily polluted area. The isolates were characterized taxonomically and physiologically. Most of these strains belonged to the genus Pseudomonas, and seven of them did not fit any previous taxonomic description. They differed from type strains in a few biochemical characteristics and in the utilization of aromatic compounds. None had catechol 1,2-dioxygenase activity, and catechol 2,3-dioxygenase was responsible for the aromatic ring cleavage. DNA hybridizations demonstrated a close relationship between two isolates and the Pseudomonas stutzeri type strain, and between five isolates and the Pseudomonas testosteroni type strain. On the basis of nutritional and enzymatic characteristics, it was assumed that the seven isolates represent new biovars belonging to the species P. testosteroni and P. stutzeri that are able to degrade aromatic hydrocarbons.

  19. Combustion characterization of beneficiated coal-based fuels

    SciTech Connect

    Chow, O.K.; Levasseur, A.A.

    1995-11-01

    The Pittsburgh Energy Technology Center (PETC) of the U.S. Department of Energy is sponsoring the development of advanced coal-cleaning technologies aimed at expanding the use of the nation`s vast coal reserves in an environmentally and economically acceptable manner. Because of the lack of practical experience with deeply beneficiated coal-based fuels, PETC has contracted Combustion Engineering, Inc. to perform a multi-year project on `Combustion Characterization of Beneficiated Coal-Based Fuels.` The objectives of this project include: (1) the development of an engineering data base which will provide detailed information on the properties of Beneficiated Coal-Based Fuels (BCs) influencing combustion, ash deposition, ash erosion, particulate collection, and emissions; and (2) the application of this technical data base to predict the performance and economic impacts of firing the BCFs in various commercial boiler designs.

  20. Mining and beneficiation: A review of possible lunar applications

    NASA Technical Reports Server (NTRS)

    Chamberlain, Peter G.

    1991-01-01

    Successful exploration of Mars and outer space may require base stations strategically located on the Moon. Such bases must develop a certain self-sufficiency, particularly in the critical life support materials, fuel components, and construction materials. Technology is reviewed for the first steps in lunar resource recovery-mining and beneficiation. The topic is covered in three main categories: site selection; mining; and beneficiation. It will also include (in less detail) in-situ processes. The text described mining technology ranging from simple diggings and hauling vehicles (the strawman) to more specialized technology including underground excavation methods. The section of beneficiation emphasizes dry separation techniques and methods of sorting the ore by particle size. In-situ processes, chemical and thermal, are identified to stimulate further thinking by future researchers.

  1. Beneficial effects of lactic acid bacteria on human beings.

    PubMed

    Masood, Muhammad Irfan; Qadir, Muhammad Imran; Shirazi, Jafir Hussain; Khan, Ikram Ullah

    2011-02-01

    Lactic acid bacteria are a diverse group of bacteria that produce lactic acid as their major fermented product. Most of them are normal flora of human being and animals and produce myriad beneficial effects for human beings include, alleviation of lactose intolerance, diarrhea, peptic ulcer, stimulation of immune system, antiallergic effects, antifungal actions, preservation of food, and prevention of colon cancer. This review highlights the potential species of Lactic acid bacteria responsible for producing these effects. It has been concluded that lactic acid bacteria are highly beneficial microorganisms for human beings and are present abundantly in dairy products so their use should be promoted for good human health.

  2. Beneficial effects of lactic acid bacteria on human beings.

    PubMed

    Masood, Muhammad Irfan; Qadir, Muhammad Imran; Shirazi, Jafir Hussain; Khan, Ikram Ullah

    2011-02-01

    Lactic acid bacteria are a diverse group of bacteria that produce lactic acid as their major fermented product. Most of them are normal flora of human being and animals and produce myriad beneficial effects for human beings include, alleviation of lactose intolerance, diarrhea, peptic ulcer, stimulation of immune system, antiallergic effects, antifungal actions, preservation of food, and prevention of colon cancer. This review highlights the potential species of Lactic acid bacteria responsible for producing these effects. It has been concluded that lactic acid bacteria are highly beneficial microorganisms for human beings and are present abundantly in dairy products so their use should be promoted for good human health. PMID:21162695

  3. Cytokinin production by Pseudomonas fluorescens G20-18 determines biocontrol activity against Pseudomonas syringae in Arabidopsis

    PubMed Central

    Großkinsky, Dominik K.; Tafner, Richard; Moreno, María V.; Stenglein, Sebastian A.; García de Salamone, Inés E.; Nelson, Louise M.; Novák, Ondřej; Strnad, Miroslav; van der Graaff, Eric; Roitsch, Thomas

    2016-01-01

    Plant beneficial microbes mediate biocontrol of diseases by interfering with pathogens or via strengthening the host. Although phytohormones, including cytokinins, are known to regulate plant development and physiology as well as plant immunity, their production by microorganisms has not been considered as a biocontrol mechanism. Here we identify the ability of Pseudomonas fluorescens G20-18 to efficiently control P. syringae infection in Arabidopsis, allowing maintenance of tissue integrity and ultimately biomass yield. Microbial cytokinin production was identified as a key determinant for this biocontrol effect on the hemibiotrophic bacterial pathogen. While cytokinin-deficient loss-of-function mutants of G20-18 exhibit impaired biocontrol, functional complementation with cytokinin biosynthetic genes restores cytokinin-mediated biocontrol, which is correlated with differential cytokinin levels in planta. Arabidopsis mutant analyses revealed the necessity of functional plant cytokinin perception and salicylic acid-dependent defence signalling for this biocontrol mechanism. These results demonstrate microbial cytokinin production as a novel microbe-based, hormone-mediated concept of biocontrol. This mechanism provides a basis to potentially develop novel, integrated plant protection strategies combining promotion of growth, a favourable physiological status and activation of fine-tuned direct defence and abiotic stress resilience. PMID:26984671

  4. Cytokinin production by Pseudomonas fluorescens G20-18 determines biocontrol activity against Pseudomonas syringae in Arabidopsis.

    PubMed

    Großkinsky, Dominik K; Tafner, Richard; Moreno, María V; Stenglein, Sebastian A; García de Salamone, Inés E; Nelson, Louise M; Novák, Ondřej; Strnad, Miroslav; van der Graaff, Eric; Roitsch, Thomas

    2016-01-01

    Plant beneficial microbes mediate biocontrol of diseases by interfering with pathogens or via strengthening the host. Although phytohormones, including cytokinins, are known to regulate plant development and physiology as well as plant immunity, their production by microorganisms has not been considered as a biocontrol mechanism. Here we identify the ability of Pseudomonas fluorescens G20-18 to efficiently control P. syringae infection in Arabidopsis, allowing maintenance of tissue integrity and ultimately biomass yield. Microbial cytokinin production was identified as a key determinant for this biocontrol effect on the hemibiotrophic bacterial pathogen. While cytokinin-deficient loss-of-function mutants of G20-18 exhibit impaired biocontrol, functional complementation with cytokinin biosynthetic genes restores cytokinin-mediated biocontrol, which is correlated with differential cytokinin levels in planta. Arabidopsis mutant analyses revealed the necessity of functional plant cytokinin perception and salicylic acid-dependent defence signalling for this biocontrol mechanism. These results demonstrate microbial cytokinin production as a novel microbe-based, hormone-mediated concept of biocontrol. This mechanism provides a basis to potentially develop novel, integrated plant protection strategies combining promotion of growth, a favourable physiological status and activation of fine-tuned direct defence and abiotic stress resilience. PMID:26984671

  5. Genome Sequences of Pseudomonas oryzihabitans Phage POR1 and Pseudomonas aeruginosa Phage PAE1

    PubMed Central

    Dyson, Zoe A.; Seviour, Robert J.; Tucci, Joseph

    2016-01-01

    We report the genome sequences of two double-stranded DNA siphoviruses, POR1 infective for Pseudomonas oryzihabitans and PAE1 infective for Pseudomonas aeruginosa. The phage POR1 genome showed no nucleotide sequence homology to any other DNA phage sequence in the GenBank database, while phage PAE1 displayed synteny to P. aeruginosa phages M6, MP1412, and YuA. PMID:27313312

  6. Genome Sequences of Pseudomonas oryzihabitans Phage POR1 and Pseudomonas aeruginosa Phage PAE1.

    PubMed

    Dyson, Zoe A; Seviour, Robert J; Tucci, Joseph; Petrovski, Steve

    2016-06-16

    We report the genome sequences of two double-stranded DNA siphoviruses, POR1 infective for Pseudomonas oryzihabitans and PAE1 infective for Pseudomonas aeruginosa The phage POR1 genome showed no nucleotide sequence homology to any other DNA phage sequence in the GenBank database, while phage PAE1 displayed synteny to P. aeruginosa phages M6, MP1412, and YuA.

  7. Genome Sequences of Pseudomonas oryzihabitans Phage POR1 and Pseudomonas aeruginosa Phage PAE1.

    PubMed

    Dyson, Zoe A; Seviour, Robert J; Tucci, Joseph; Petrovski, Steve

    2016-01-01

    We report the genome sequences of two double-stranded DNA siphoviruses, POR1 infective for Pseudomonas oryzihabitans and PAE1 infective for Pseudomonas aeruginosa The phage POR1 genome showed no nucleotide sequence homology to any other DNA phage sequence in the GenBank database, while phage PAE1 displayed synteny to P. aeruginosa phages M6, MP1412, and YuA. PMID:27313312

  8. Chemotaxis of Pseudomonas putida toward chlorinated benzoates

    SciTech Connect

    Harwood, C.S.; Parales, R.E.; Dispensa, M. )

    1990-05-01

    The chlorinated aromatic acids 3-chlorobenzoate and 4-chlorobenzoate are chemoattractants for Pseudomonas putida PRS2000. These compounds are detected by a chromosomally encoded chemotactic response to benzoate which is inducible by {beta}-ketoadipate, and intermediate of benzoate catabolism. Plasmid pAC27, encoding enzymes for 3-chlorobenzoate degradation, does not appear to carry genes for chemotaxis toward chlorinated compounds.

  9. New Pseudomonas spp. Are Pathogenic to Citrus.

    PubMed

    Beiki, Farid; Busquets, Antonio; Gomila, Margarita; Rahimian, Heshmat; Lalucat, Jorge; García-Valdés, Elena

    2016-01-01

    Five putative novel Pseudomonas species shown to be pathogenic to citrus have been characterized in a screening of 126 Pseudomonas strains isolated from diseased citrus leaves and stems in northern Iran. The 126 strains were studied using a polyphasic approach that included phenotypic characterizations and phylogenetic multilocus sequence analysis. The pathogenicity of these strains against 3 cultivars of citrus is demonstrated in greenhouse and field studies. The strains were initially grouped phenotypically and by their partial rpoD gene sequences into 11 coherent groups in the Pseudomonas fluorescens phylogenetic lineage. Fifty-three strains that are representatives of the 11 groups were selected and analyzed by partial sequencing of their 16S rRNA and gyrB genes. The individual and concatenated partial sequences of the three genes were used to construct the corresponding phylogenetic trees. The majority of the strains were identified at the species level: P. lurida (5 strains), P. monteilii (2 strains), P. moraviensis (1 strain), P. orientalis (16 strains), P. simiae (7 strains), P. syringae (46 strains, distributed phylogenetically in at least 5 pathovars), and P. viridiflava (2 strains). This is the first report of pathogenicity on citrus of P. orientalis, P. simiae, P. lurida, P. moraviensis and P. monteilii strains. The remaining 47 strains that could not be identified at the species level are considered representatives of at least 5 putative novel Pseudomonas species that are not yet described.

  10. Genome Sequence of Pseudomonas chlororaphis Strain 189

    PubMed Central

    Town, Jennifer; Audy, Patrice; Boyetchko, Susan M.

    2016-01-01

    Pseudomonas chlororaphis strain 189 is a potent inhibitor of the growth of the potato pathogen Phytophthora infestans. We determined the complete, finished sequence of the 6.8-Mbp genome of this strain, consisting of a single contiguous molecule. Strain 189 is closely related to previously sequenced strains of P. chlororaphis. PMID:27340063

  11. New Pseudomonas spp. Are Pathogenic to Citrus.

    PubMed

    Beiki, Farid; Busquets, Antonio; Gomila, Margarita; Rahimian, Heshmat; Lalucat, Jorge; García-Valdés, Elena

    2016-01-01

    Five putative novel Pseudomonas species shown to be pathogenic to citrus have been characterized in a screening of 126 Pseudomonas strains isolated from diseased citrus leaves and stems in northern Iran. The 126 strains were studied using a polyphasic approach that included phenotypic characterizations and phylogenetic multilocus sequence analysis. The pathogenicity of these strains against 3 cultivars of citrus is demonstrated in greenhouse and field studies. The strains were initially grouped phenotypically and by their partial rpoD gene sequences into 11 coherent groups in the Pseudomonas fluorescens phylogenetic lineage. Fifty-three strains that are representatives of the 11 groups were selected and analyzed by partial sequencing of their 16S rRNA and gyrB genes. The individual and concatenated partial sequences of the three genes were used to construct the corresponding phylogenetic trees. The majority of the strains were identified at the species level: P. lurida (5 strains), P. monteilii (2 strains), P. moraviensis (1 strain), P. orientalis (16 strains), P. simiae (7 strains), P. syringae (46 strains, distributed phylogenetically in at least 5 pathovars), and P. viridiflava (2 strains). This is the first report of pathogenicity on citrus of P. orientalis, P. simiae, P. lurida, P. moraviensis and P. monteilii strains. The remaining 47 strains that could not be identified at the species level are considered representatives of at least 5 putative novel Pseudomonas species that are not yet described. PMID:26919540

  12. Pseudomonas sepsis with Noma: an association?

    PubMed

    Vaidyanathan, S; Tullu, M S; Lahiri, K R; Deshmukh, C T

    2005-08-01

    We report here a 2.5-year-old male child with community-acquired Pseudomonal sepsis showing the characteristic lesions of ecthyma gangrenosum. The child had development of gangrenous changes of the nose and face - the 'cancrum oris' or 'Noma'. We highlight the possible association of Pseudomonas sepsis and Noma, with malnutrition playing a central role in causing both the diseases.

  13. New Pseudomonas spp. Are Pathogenic to Citrus

    PubMed Central

    Beiki, Farid; Busquets, Antonio; Gomila, Margarita; Rahimian, Heshmat; Lalucat, Jorge; García-Valdés, Elena

    2016-01-01

    Five putative novel Pseudomonas species shown to be pathogenic to citrus have been characterized in a screening of 126 Pseudomonas strains isolated from diseased citrus leaves and stems in northern Iran. The 126 strains were studied using a polyphasic approach that included phenotypic characterizations and phylogenetic multilocus sequence analysis. The pathogenicity of these strains against 3 cultivars of citrus is demonstrated in greenhouse and field studies. The strains were initially grouped phenotypically and by their partial rpoD gene sequences into 11 coherent groups in the Pseudomonas fluorescens phylogenetic lineage. Fifty-three strains that are representatives of the 11 groups were selected and analyzed by partial sequencing of their 16S rRNA and gyrB genes. The individual and concatenated partial sequences of the three genes were used to construct the corresponding phylogenetic trees. The majority of the strains were identified at the species level: P. lurida (5 strains), P. monteilii (2 strains), P. moraviensis (1 strain), P. orientalis (16 strains), P. simiae (7 strains), P. syringae (46 strains, distributed phylogenetically in at least 5 pathovars), and P. viridiflava (2 strains). This is the first report of pathogenicity on citrus of P. orientalis, P. simiae, P. lurida, P. moraviensis and P. monteilii strains. The remaining 47 strains that could not be identified at the species level are considered representatives of at least 5 putative novel Pseudomonas species that are not yet described. PMID:26919540

  14. OPTIMIZATION OF COAL BENEFICIATION PLANTS FOR SO2 EMISSIONS CONTROL

    EPA Science Inventory

    The article describes an optimization model for estimating the properties and cost of washed coal from coal beneficiation plants of varying levels of complexity. he design and technical description of the plant performance model are presented, together with cost algorithms for th...

  15. Beneficial effects of berryfruit polyphenols on neuronal behavioral aging

    Technology Transfer Automated Retrieval System (TEKTRAN)

    It is becoming increasingly clear that although there is a great deal of research being devoted to elucidating the molecular mechanisms involved in aging, practical information on how to forestall or reverse the deleterious effects of aging may be years away. Therefore, it may be beneficial to dete...

  16. Health-beneficial effects of probiotics: Its mode of action.

    PubMed

    Ohashi, Yuji; Ushida, Kazunari

    2009-08-01

    It is now widely recognized that probiotics have health-beneficial effects on humans and animals. Probiotics should survive in the intestinal tract to exert beneficial effects on the host's health. To keep a sufficient level of probiotic bacteria in the gastrointestinal tract, a shorter interval between doses may be required. Although adherence to the intestinal epithelial cell and mucus is not a universal property of probiotics, high ability to adhere to the intestinal surface might strongly interfere with infection of pathogenic bacteria and regulate the immune system. The administration of probiotic Lactobacillus stimulated indigenous Lactobacilli and the production of short-chain fatty acids. This alteration of the intestinal environment should contribute to maintain the host's health. The immunomodulatory effects of probiotics are related to important parts of their beneficial effects. Probiotics may modulate the intestinal immune response through the stimulation of certain cytokine and IgA secretion in intestinal mucosa. The health-beneficial effects, in particular the immunomodulation effect, of probiotics depend on the strain used. Differences in indigenous intestinal microflora significantly alter the magnitude of the effects of a probiotic. Specific probiotic strains suitable for each animal species and their life stage as well as each individual should be found.

  17. Survival probability of beneficial mutations in bacterial batch culture.

    PubMed

    Wahl, Lindi M; Zhu, Anna Dai

    2015-05-01

    The survival of rare beneficial mutations can be extremely sensitive to the organism's life history and the trait affected by the mutation. Given the tremendous impact of bacteria in batch culture as a model system for the study of adaptation, it is important to understand the survival probability of beneficial mutations in these populations. Here we develop a life-history model for bacterial populations in batch culture and predict the survival of mutations that increase fitness through their effects on specific traits: lag time, fission time, viability, and the timing of stationary phase. We find that if beneficial mutations are present in the founding population at the beginning of culture growth, mutations that reduce the mortality of daughter cells are the most likely to survive drift. In contrast, of mutations that occur de novo during growth, those that delay the onset of stationary phase are the most likely to survive. Our model predicts that approximately fivefold population growth between bottlenecks will optimize the occurrence and survival of beneficial mutations of all four types. This prediction is relatively insensitive to other model parameters, such as the lag time, fission time, or mortality rate of the population. We further estimate that bottlenecks that are more severe than this optimal prediction substantially reduce the occurrence and survival of adaptive mutations.

  18. Stabilized thermally beneficiated low rank coal and method of manufacture

    DOEpatents

    Viall, Arthur J.; Richards, Jeff M.

    1999-01-01

    A process for reducing the spontaneous combustion tendencies of thermally beneficiated low rank coals employing heat, air or an oxygen containing gas followed by an optional moisture addition. Specific reaction conditions are supplied along with knowledge of equipment types that may be employed on a commercial scale to complete the process.

  19. Stabilized thermally beneficiated low rank coal and method of manufacture

    DOEpatents

    Viall, A.J.; Richards, J.M.

    1999-01-26

    A process is described for reducing the spontaneous combustion tendencies of thermally beneficiated low rank coals employing heat, air or an oxygen containing gas followed by an optional moisture addition. Specific reaction conditions are supplied along with knowledge of equipment types that may be employed on a commercial scale to complete the process. 3 figs.

  20. Stabilized thermally beneficiated low rank coal and method of manufacture

    DOEpatents

    Viall, Arthur J.; Richards, Jeff M.

    2000-01-01

    A process for reducing the spontaneous combustion tendencies of thermally beneficiated low rank coals employing heat, air or an oxygen containing gas followed by an optional moisture addition. Specific reaction conditions are supplied along with knowledge of equipment types that may be employed on a commercial scale to complete the process.

  1. Enhancing the health-beneficial qualities of whole grain rice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Various pre- and post-harvest approaches (i.e. pre-germination of whole grains and reduced milling degree) to enhancing the health beneficial compounds of whole grain and milled rice have been reported. A discussion of the results from our pre-harvest efforts is as follows. The majority of rice cons...

  2. The non-target impact of spinosyns on beneficial arthropods.

    PubMed

    Biondi, Antonio; Mommaerts, Veerle; Smagghe, Guy; Viñuela, Elisa; Zappalà, Lucia; Desneux, Nicolas

    2012-12-01

    Spinosyn-based products, mostly spinosad, have been widely recommended by extension specialists and agribusiness companies; consequently, they have been used to control various pests in many different cropping systems. Following the worldwide adoption of spinosad-based products for integrated and organic farming, an increasing number of ecotoxicological studies have been published in the past 10 years. These studies are primarily related to the risk assessment of spinosad towards beneficial arthropods. This review takes into account recent data with the aim of (i) highlighting potentially adverse effects of spinosyns on beneficial arthropods (and hence on ecosystem services that they provide in agroecosystems), (ii) clarifying the range of methods used to address spinosyn side effects on biocontrol agents and pollinators in order to provide new insights for the development of more accurate bioassays, (iii) identifying pitfalls when analysing laboratory results to assess field risks and (iv) gaining increasing knowledge on side effects when using spinosad for integrated pest management (IPM) programmes and organic farming. For the first time, a thorough review of possible risks of spinosad and novel spinosyns (such as spinetoram) to beneficial arthropods (notably natural enemies and pollinators) is provided. The acute lethal effect and multiple sublethal effects have been identified in almost all arthropod groups studied. This review will help to optimise the future use of spinosad and new spinosyns in IPM programmes and for organic farming, notably by preventing the possible side effects of spinosyns on beneficial arthropods.

  3. Factitious foods to reduce production costs of beneficial insects

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This article reports the use of factitious foods such as Tenebrio molitor pupa, E. kuehniella eggs, Ephestia eggs, and or Artemia franciscana eggs for the rearing of beneficial insect such as Podisus maculiventris, spined soldier bug and several ladybird predators belonging to the Coccinellidae fam...

  4. Control of the peachtree borer using beneficial nematodes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The peachtree borer, Synanthedon exitiosa, is a major pest of peaches and other stone fruits. Our research indicates that entomopathogenic nematodes, also known as beneficial nematodes, can be used effectively to control the insect. We conducted replicated experiments in randomized block designs ov...

  5. Acceptance for Beneficial Use Pumping Instrumentation and Control Skid M

    SciTech Connect

    KOCH, M.R.

    2000-01-24

    This document is a Final Acceptance for Beneficial Use (ABU) for the readiness of Pumping Instrumentation and Control (PIC) skid ''M''. All the testing and documentation for PIC skid ''M'' is completed and the skid is ready for use in the field for pumping of tank U-102.

  6. Children's Illnesses: Their Beneficial Effects on Behavioral Development.

    ERIC Educational Resources Information Center

    Parmelee, Arthur H. Jr.

    1986-01-01

    Discusses potential beneficial effects of children's illnesses on their behavioral development. It is argued, on the basis of clinical experience and related research, that minor illnesses give children many opportunities to increase knowledge of self, other, prosocial behavior, and empathy and to realistically understand the sick role. (Author/RH)

  7. The genomic basis of adaptation to the fitness cost of rifampicin resistance in Pseudomonas aeruginosa.

    PubMed

    Qi, Qin; Toll-Riera, Macarena; Heilbron, Karl; Preston, Gail M; MacLean, R Craig

    2016-01-13

    Antibiotic resistance carries a fitness cost that must be overcome in order for resistance to persist over the long term. Compensatory mutations that recover the functional defects associated with resistance mutations have been argued to play a key role in overcoming the cost of resistance, but compensatory mutations are expected to be rare relative to generally beneficial mutations that increase fitness, irrespective of antibiotic resistance. Given this asymmetry, population genetics theory predicts that populations should adapt by compensatory mutations when the cost of resistance is large, whereas generally beneficial mutations should drive adaptation when the cost of resistance is small. We tested this prediction by determining the genomic mechanisms underpinning adaptation to antibiotic-free conditions in populations of the pathogenic bacterium Pseudomonas aeruginosa that carry costly antibiotic resistance mutations. Whole-genome sequencing revealed that populations founded by high-cost rifampicin-resistant mutants adapted via compensatory mutations in three genes of the RNA polymerase core enzyme, whereas populations founded by low-cost mutants adapted by generally beneficial mutations, predominantly in the quorum-sensing transcriptional regulator gene lasR. Even though the importance of compensatory evolution in maintaining resistance has been widely recognized, our study shows that the roles of general adaptation in maintaining resistance should not be underestimated and highlights the need to understand how selection at other sites in the genome influences the dynamics of resistance alleles in clinical settings.

  8. The genomic basis of adaptation to the fitness cost of rifampicin resistance in Pseudomonas aeruginosa

    PubMed Central

    Toll-Riera, Macarena; Heilbron, Karl

    2016-01-01

    Antibiotic resistance carries a fitness cost that must be overcome in order for resistance to persist over the long term. Compensatory mutations that recover the functional defects associated with resistance mutations have been argued to play a key role in overcoming the cost of resistance, but compensatory mutations are expected to be rare relative to generally beneficial mutations that increase fitness, irrespective of antibiotic resistance. Given this asymmetry, population genetics theory predicts that populations should adapt by compensatory mutations when the cost of resistance is large, whereas generally beneficial mutations should drive adaptation when the cost of resistance is small. We tested this prediction by determining the genomic mechanisms underpinning adaptation to antibiotic-free conditions in populations of the pathogenic bacterium Pseudomonas aeruginosa that carry costly antibiotic resistance mutations. Whole-genome sequencing revealed that populations founded by high-cost rifampicin-resistant mutants adapted via compensatory mutations in three genes of the RNA polymerase core enzyme, whereas populations founded by low-cost mutants adapted by generally beneficial mutations, predominantly in the quorum-sensing transcriptional regulator gene lasR. Even though the importance of compensatory evolution in maintaining resistance has been widely recognized, our study shows that the roles of general adaptation in maintaining resistance should not be underestimated and highlights the need to understand how selection at other sites in the genome influences the dynamics of resistance alleles in clinical settings. PMID:26763710

  9. The biocontrol bacterium Pseudomonas fluorescens Pf29Arp strain affects the pathogenesis-related gene expression of the take-all fungus Gaeumannomyces graminis var. tritici on wheat roots

    PubMed Central

    Daval, Stéphanie; Lebreton, Lionel; Gazengel, Kévin; Boutin, Morgane; Guillerm-Erckelboudt, Anne-Yvonne; Sarniguet, Alain

    2011-01-01

    The main effects of antagonistic rhizobacteria on plant pathogenic fungi are antibiosis, fungistasis or an indirect constraint through the induction of a plant defence response. To explore different biocontrol mechanisms, an in vitro confrontation assay was conducted with the rhizobacterium Pseudomonas fluorescens Pf29Arp as a biocontrol agent of the fungus Gaeumannomyces graminis var. tritici (Ggt) on wheat roots. In parallel with the assessment of disease extension, together with the bacterial and fungal root colonization rates, the transcript levels of candidate fungal pathogenicity and plant-induced genes were monitored during the 10-day infection process. The bacterial inoculation of wheat roots with the Pf29Arp strain reduced the development of Ggt-induced disease expressed as attack frequency and necrosis length. The growth rates of Ggt and Pf29Arp, monitored through quantitative polymerase chain reaction of DNA amounts with a part of the Ggt 18S rDNA gene and a specific Pf29Arp strain detection probe, respectively, increased throughout the interactions. Bacterial antagonism and colonization had no significant effect on root colonization by Ggt. The expression of fungal and plant genes was quantified in planta by quantitative reverse transcription-polymerase chain reaction during the interactions thanks to the design of specific primers and an innovative universal reference system. During the early stages of the tripartite interaction, several of the fungal genes assayed were down-regulated by Pf29Arp, including two laccases, a β-1,3-exoglucanase and a mitogen-activated protein kinase. The plant host glutathione-S-transferase gene was induced by Ggt alone and up-regulated by Pf29Arp bacteria in interaction with the pathogen. We conclude that Pf29Arp antagonism acts through the alteration of fungal pathogenesis and probably through the activation of host defences. PMID:21726382

  10. Maximising the secondary beneficial effects of larval debridement therapy.

    PubMed

    Pritchard, D I; Nigam, Y

    2013-11-01

    Laboratory-based clinical investigations have shown that maggots and their secretions promote, among other activities, fibroblast motogenesis and angiogenesis. These events would contribute to re-granulation if translated to the wound environment. Maggot secretions also have ascribed antibacterial actions and may exhibit anti-inflammatory effects. Many of these biological events would be lost in the presence of necrotic tissue, making debridement a prerequisite for the release of larval-secreted secondary beneficial effects on the wound. We argue that Larval Debridement Therapy (LDT) should be considered as a primary and secondary treatment in wound management, with the primary application designed to debride the wound, and with subsequent applications to the debrided wound targeted to cellular events that promote healing. This review lends support to a re-evaluation of larval application protocols, in order to optimally harness the potential secondary beneficial clinical effects of larval therapy.

  11. Technologies for Beneficial Microorganisms Inocula Used as Biofertilizers

    PubMed Central

    Malusá, E.; Sas-Paszt, L.; Ciesielska, J.

    2012-01-01

    The increasing need for environmentaly friendly agricultural practices is driving the use of fertilizers based on beneficial microorganisms. The latter belong to a wide array of genera, classes, and phyla, ranging from bacteria to yeasts and fungi, which can support plant nutrition with different mechanisms. Moreover, studies on the interactions between plant, soil, and the different microorganisms are shedding light on their interrelationships thus providing new possible ways to exploit them for agricultural purposes. However, even though the inoculation of plants with these microorganisms is a well-known practice, the formulation of inocula with a reliable and consistent effect under field conditions is still a bottleneck for their wider use. The choice of the technology for inocula production and of the carrier for the formulation is key to their successful application. This paper focuses on how inoculation issues can be approached to improve the performance of beneficial microorganisms used as a tool for enhancing plant growth and yield. PMID:22547984

  12. Energy Drink Consumption: Beneficial and Adverse Health Effects

    PubMed Central

    Alsunni, Ahmed Abdulrahman

    2015-01-01

    Consumption of energy drinks has been increasing dramatically in the last two decades, particularly amongst adolescents and young adults. Energy drinks are aggressively marketed with the claim that these products give an energy boost to improve physical and cognitive performance. However, studies supporting these claims are limited. In fact, several adverse health effects have been related to energy drink; this has raised the question of whether these beverages are safe. This review was carried out to identify and discuss the published articles that examined the beneficial and adverse health effects related to energy drink. It is concluded that although energy drink may have beneficial effects on physical performance, these products also have possible detrimental health consequences. Marketing of energy drinks should be limited or forbidden until independent research confirms their safety, particularly among adolescents. PMID:26715927

  13. Acceptance for Beneficial Use Pumping Instrumentation and Control Skid N

    SciTech Connect

    KOCH, M.R.

    2000-03-13

    This is a final Acceptance for Beneficial Use (ABU) for Pumping and Instrumentation Control (PIC) skid ''N''. PIC skid ''N'' is ready for pumping tank U-109. All the testing and documentation has been completed as required on the AE3U checklist. This AE3U covers only the readiness of the PIC skid ''N''. Other U-farm preparations including dilution tank fabrication, portable exhauster readiness, leak detection, valve pit preparation, and the Operation Control Station readiness are not part of this ABU. PIC skid ''N'' is a new skid fabricated and tested at Site Fabrication Services. The skid controls the jet pump and monitors various instruments associated with the pumping operation. This monitoring includes leak detection along the waste transfer route and flammable gases in the pump pit. This Acceptance for Beneficial Use documents that Pumping Instrumentation and Control (PIC) skid ''N'' is ready for field use. This document does not cover the field installation or operational testing.

  14. Energy Drink Consumption: Beneficial and Adverse Health Effects.

    PubMed

    Alsunni, Ahmed Abdulrahman

    2015-10-01

    Consumption of energy drinks has been increasing dramatically in the last two decades, particularly amongst adolescents and young adults. Energy drinks are aggressively marketed with the claim that these products give an energy boost to improve physical and cognitive performance. However, studies supporting these claims are limited. In fact, several adverse health effects have been related to energy drink; this has raised the question of whether these beverages are safe. This review was carried out to identify and discuss the published articles that examined the beneficial and adverse health effects related to energy drink. It is concluded that although energy drink may have beneficial effects on physical performance, these products also have possible detrimental health consequences. Marketing of energy drinks should be limited or forbidden until independent research confirms their safety, particularly among adolescents. PMID:26715927

  15. Biosolids recycling: Beneficial technology for a better environment

    SciTech Connect

    Not Available

    1994-06-01

    The booklet is written to provide an understanding of the great value that can be derived from the beneficial use of biosolids. The booklet then briefly discusses important aspects of its new regulation (40 Code of Federal Regulations Part 503) that govern the final use or disposal of biosolids. It concludes with a discussion of the scientific basis of the rule and names of people and references to contact for additional information regarding the rule and risk assessment.

  16. Beneficiation of lunar rocks and regolith - Concepts and difficulties

    NASA Technical Reports Server (NTRS)

    Taylor, Lawrence A.; Mckay, David S.

    1992-01-01

    Some of the inherent differences between lunar rocks and the finer portion of the regolith, the soil, are discussed. A brief outline of the formation of lunar soil is presented. Beneficiation of rocks vs regolith for the production of an ilmenite feedstock is addressed in particular, but the concepts and principles considered are applicable to other situations as well. The overall systems design must take the range of available feedstocks into account. Decisions on design that will influence feedstock requirements must be made.

  17. Potential beneficial uses of coalbed natural gas (CBNG) water.

    PubMed

    Reddy, K J; Whitman, Ashley J; Kniss, Andrew R

    2014-01-01

    The CBNG well water is typically managed by discharging into nearby disposal ponds. The CBNG well water could potentially be very useful in the water-limited regions (e.g., arid and semi-arid), but beneficial uses may be hindered by water quality problems. Objectives of this research were to: (1) examine trend analysis of nine years of CBNG well water at discharge (outfall) points and in corresponding disposal ponds, (2) evaluate geochemical processes, (3) identify potential water quality issues, and (4) find potential beneficial uses. The CBNG well water at discharge points and in corresponding disposal ponds was measured on-site for pH and electrical conductivity (EC). These water samples were also analyzed in the laboratory for calcium (Ca), sodium (Na), magnesium (Mg), potassium (K), iron (Fe), aluminum (Al), copper (Cu), arsenic (As), selenium (Se), cadmium (Cd), and barium (Ba). Total dissolved solids (TDS) were calculated from EC measurements. The sodium adsorption ratio (SAR) was calculated from Na, Ca, and Mg concentrations. Trend analyses of outfalls and disposal ponds were conducted separately so that the differences in trends could be compared. Trends in CBNG well water at discharge points are not always the same as trends in CBNG disposal ponds: environmental and geochemical processes play an important role in the water quality of these well waters. Overall trend analyses suggest that CBNG well water at discharge points in all basins of the Powder River Basin meets beneficial use criteria, except for SAR and to some extent EC, for aquatic life, livestock and wildlife watering, and irrigation. The CBNG well water in disposal ponds across all basins meets criteria for all beneficial uses except for As, pH, SAR, and to some extent EC for irrigation, aquatic life, and livestock and wildlife watering. PMID:24280972

  18. Chemotaxis signaling systems in model beneficial plant-bacteria associations.

    PubMed

    Scharf, Birgit E; Hynes, Michael F; Alexandre, Gladys M

    2016-04-01

    Beneficial plant-microbe associations play critical roles in plant health. Bacterial chemotaxis provides a competitive advantage to motile flagellated bacteria in colonization of plant root surfaces, which is a prerequisite for the establishment of beneficial associations. Chemotaxis signaling enables motile soil bacteria to sense and respond to gradients of chemical compounds released by plant roots. This process allows bacteria to actively swim towards plant roots and is thus critical for competitive root surface colonization. The complete genome sequences of several plant-associated bacterial species indicate the presence of multiple chemotaxis systems and a large number of chemoreceptors. Further, most soil bacteria are motile and capable of chemotaxis, and chemotaxis-encoding genes are enriched in the bacteria found in the rhizosphere compared to the bulk soil. This review compares the architecture and diversity of chemotaxis signaling systems in model beneficial plant-associated bacteria and discusses their relevance to the rhizosphere lifestyle. While it is unclear how controlling chemotaxis via multiple parallel chemotaxis systems provides a competitive advantage to certain bacterial species, the presence of a larger number of chemoreceptors is likely to contribute to the ability of motile bacteria to survive in the soil and to compete for root surface colonization.

  19. Inferring the age of a fixed beneficial allele.

    PubMed

    Ormond, Louise; Foll, Matthieu; Ewing, Gregory B; Pfeifer, Susanne P; Jensen, Jeffrey D

    2016-01-01

    Estimating the age and strength of beneficial alleles is central to understanding how adaptation proceeds in response to changing environmental conditions. Several haplotype-based estimators exist for inferring the age of segregating beneficial mutations. Here, we develop an approximate Bayesian-based approach that rather estimates these parameters for fixed beneficial mutations in single populations. We integrate a range of existing diversity, site frequency spectrum, haplotype- and linkage disequilibrium-based summary statistics. We show that for strong selective sweeps on de novo mutations the method can estimate allele age and selection strength even in nonequilibrium demographic scenarios. We extend our approach to models of selection on standing variation, and co-infer the frequency at which selection began to act upon the mutation. Finally, we apply our method to estimate the age and selection strength of a previously identified mutation underpinning cryptic colour adaptation in a wild deer mouse population, and compare our findings with previously published estimates as well as with geological data pertaining to the presumed shift in selective pressure. PMID:26576754

  20. Microbial Beneficiation of Salem Iron Ore Using Penicillium purpurogenum

    NASA Astrophysics Data System (ADS)

    Mishra, M.; Pradhan, M.; Sukla, L. B.; Mishra, B. K.

    2011-02-01

    High alumina and silica content in the iron ore affects coke rate, reducibility, and productivity in a blast furnace. Iron ore is being beneficiated all around the world to meet the quality requirement of iron and steel industries. Choosing a beneficiation treatment depends on the nature of the gangue present and its association with the ore structure. The advanced physicochemical methods used for the beneficiation of iron ore are generally unfriendly to the environment. Biobeneficiation is considered to be ecofriendly, promising, and revolutionary solutions to these problems. A characterization study of Salem iron ore indicates that the major iron-bearing minerals are hematite, magnetite, and goethite. Samples on average contains (pct) Fe2O3-84.40, Fe (total)-59.02, Al2O3-7.18, and SiO2-7.53. Penicillium purpurogenum (MTCC 7356) was used for the experiment . It removed 35.22 pct alumina and 39.41 pct silica in 30 days in a shake flask at 10 pct pulp density, 308 K (35 °C), and 150 rpm. In a bioreactor experiment at 2 kg scale using the same organism, it removed 23.33 pct alumina and 30.54 pct silica in 30 days at 300 rpm agitation and 2 to 3 l/min aeration. Alumina and silica dissolution follow the shrinking core model for both shake flask and bioreactor experiments.

  1. Adaptive walks and distribution of beneficial fitness effects.

    PubMed

    Seetharaman, Sarada; Jain, Kavita

    2014-04-01

    We study the adaptation dynamics of a maladapted asexual population on rugged fitness landscapes with many local fitness peaks. The distribution of beneficial fitness effects is assumed to belong to one of the three extreme value domains, viz. Weibull, Gumbel, and Fréchet. We work in the strong selection-weak mutation regime in which beneficial mutations fix sequentially, and the population performs an uphill walk on the fitness landscape until a local fitness peak is reached. A striking prediction of our analysis is that the fitness difference between successive steps follows a pattern of diminishing returns in the Weibull domain and accelerating returns in the Fréchet domain, as the initial fitness of the population is increased. These trends are found to be robust with respect to fitness correlations. We believe that this result can be exploited in experiments to determine the extreme value domain of the distribution of beneficial fitness effects. Our work here differs significantly from the previous ones that assume the selection coefficient to be small. On taking large effect mutations into account, we find that the length of the walk shows different qualitative trends from those derived using small selection coefficient approximation.

  2. Shale-oil-recovery systems incorporating ore beneficiation. Final report.

    SciTech Connect

    Weiss, M.A.; Klumpar, I.V.; Peterson, C.R.; Ring, T.A.

    1982-10-01

    This study analyzed the recovery of oil from oil shale by use of proposed systems which incorporate beneficiation of the shale ore (that is concentration of the kerogen before the oil-recovery step). The objective was to identify systems which could be more attractive than conventional surface retorting of ore. No experimental work was carried out. The systems analyzed consisted of beneficiation methods which could increase kerogen concentrations by at least four-fold. Potentially attractive low-enrichment methods such as density separation were not examined. The technical alternatives considered were bounded by the secondary crusher as input and raw shale oil as output. A sequence of ball milling, froth flotation, and retorting concentrate is not attractive for Western shales compared to conventional ore retorting; transporting the concentrate to another location for retorting reduces air emissions in the ore region but cost reduction is questionable. The high capital and energy cost s results largely from the ball milling step which is very inefficient. Major improvements in comminution seem achievable through research and such improvements, plus confirmation of other assumptions, could make high-enrichment beneficiation competitive with conventional processing. 27 figures, 23 tables.

  3. Impact of food disinfection on beneficial biothiol contents in vegetables.

    PubMed

    Qiang, Zhimin; Demirkol, Omca; Ercal, Nuran; Adams, Craig

    2005-12-14

    In this work we investigated the impact of food disinfection on the beneficial biothiol contents in a suite of vegetables consumed daily, including spinach, green bean, asparagus, cucumber, and red pepper. Four disinfection technologies commonly studied and/or used in food processing and preservation, including hydrogen peroxide, free chlorine, and gaseous- and aqueous-phase ozone, were examined with common dosages and contact times. Results indicate that the common disinfection technologies may result in significant loss of beneficial biothiols in vegetables which are essentially important to human health. For example, as much as 70% of biothiols were lost when spinach was treated with hydrogen peroxide (5.0 wt %) for 30 min. Approximately 48-54% of biothiols were destroyed by free chlorine and gaseous- and aqueous-phase ozone under typical contacting conditions. In red pepper, about 60-71% of reduced glutathione was oxidized by the disinfectants. The potential decrease in biothiols during disinfection was dependent upon the biothiol type, the disinfectant, and the vegetable. The effectiveness of total bacterial inactivation by the four disinfection technologies was concurrently evaluated. Results show that free chlorine is most effective, achieving disinfection efficiencies of greater than 4 log for all study vegetables. This study may provide important information for the food industry to design optimum contacting methods for vegetables to simultaneously achieve sufficient bacterial disinfection while minimizing loss of beneficial biothiols.

  4. Enhanced annotations and features for comparing thousands of Pseudomonas genomes in the Pseudomonas genome database.

    PubMed

    Winsor, Geoffrey L; Griffiths, Emma J; Lo, Raymond; Dhillon, Bhavjinder K; Shay, Julie A; Brinkman, Fiona S L

    2016-01-01

    The Pseudomonas Genome Database (http://www.pseudomonas.com) is well known for the application of community-based annotation approaches for producing a high-quality Pseudomonas aeruginosa PAO1 genome annotation, and facilitating whole-genome comparative analyses with other Pseudomonas strains. To aid analysis of potentially thousands of complete and draft genome assemblies, this database and analysis platform was upgraded to integrate curated genome annotations and isolate metadata with enhanced tools for larger scale comparative analysis and visualization. Manually curated gene annotations are supplemented with improved computational analyses that help identify putative drug targets and vaccine candidates or assist with evolutionary studies by identifying orthologs, pathogen-associated genes and genomic islands. The database schema has been updated to integrate isolate metadata that will facilitate more powerful analysis of genomes across datasets in the future. We continue to place an emphasis on providing high-quality updates to gene annotations through regular review of the scientific literature and using community-based approaches including a major new Pseudomonas community initiative for the assignment of high-quality gene ontology terms to genes. As we further expand from thousands of genomes, we plan to provide enhancements that will aid data visualization and analysis arising from whole-genome comparative studies including more pan-genome and population-based approaches. PMID:26578582

  5. Enhanced annotations and features for comparing thousands of Pseudomonas genomes in the Pseudomonas genome database

    PubMed Central

    Winsor, Geoffrey L.; Griffiths, Emma J.; Lo, Raymond; Dhillon, Bhavjinder K.; Shay, Julie A.; Brinkman, Fiona S. L.

    2016-01-01

    The Pseudomonas Genome Database (http://www.pseudomonas.com) is well known for the application of community-based annotation approaches for producing a high-quality Pseudomonas aeruginosa PAO1 genome annotation, and facilitating whole-genome comparative analyses with other Pseudomonas strains. To aid analysis of potentially thousands of complete and draft genome assemblies, this database and analysis platform was upgraded to integrate curated genome annotations and isolate metadata with enhanced tools for larger scale comparative analysis and visualization. Manually curated gene annotations are supplemented with improved computational analyses that help identify putative drug targets and vaccine candidates or assist with evolutionary studies by identifying orthologs, pathogen-associated genes and genomic islands. The database schema has been updated to integrate isolate metadata that will facilitate more powerful analysis of genomes across datasets in the future. We continue to place an emphasis on providing high-quality updates to gene annotations through regular review of the scientific literature and using community-based approaches including a major new Pseudomonas community initiative for the assignment of high-quality gene ontology terms to genes. As we further expand from thousands of genomes, we plan to provide enhancements that will aid data visualization and analysis arising from whole-genome comparative studies including more pan-genome and population-based approaches. PMID:26578582

  6. Generalized Transduction in the Phytopathogen Pseudomonas syringae.

    PubMed

    Nordeen, R O; Currier, T C

    1983-06-01

    Bacteriophages isolated from culture supernatants of Pseudomonas syringae pv. syringae and from sewage transferred various chromosomal genes to P. syringae PS224. Linkage between arginine and tryptophan loci was demonstrated. The number of transductants recovered per milliliter was not altered appreciably by UV irradiation of selected phage isolates. In addition, the presence of the IncP2 plasmid R38 in a P. syringae PS224 arginine auxotroph did not increase the transduction frequency as it does in Pseudomonas aeruginosa. Increasing the multiplicity of infection of transducing phage Pssy15 from 1 to 10 resulted in up to a 10-fold increase in the number of transductants recovered, although the actual transductional frequency remained about the same. Treatment of transduction mixtures with DNase did not affect transductional frequency.

  7. Designing recombinant Pseudomonas strains to enhance biodesulfurization.

    PubMed Central

    Gallardo, M E; Ferrández, A; De Lorenzo, V; García, J L; Díaz, E

    1997-01-01

    The dsz biodesulfurization cluster from Rhodococcus erythropolis IGTS8 has been engineered under the control of heterologous broad-host-range regulatory signals to alleviate the mechanism of sulfur repression, and it was stably inserted into the chromosomes of different Pseudomonas strains. The recombinant bacteria were able to desulfurize dibenzothiophene more efficiently than the native host. Furthermore, these new biocatalysts combine relevant industrial and environmental traits, such as production of biosurfactants, with the enhanced biodesulfurization phenotype. PMID:9371464

  8. Using Pseudomonas spp. for Integrated Biological Control.

    PubMed

    Stockwell, Virginia O; Stack, James P

    2007-02-01

    ABSTRACT Pseudomonas spp. have been studied for decades as model organisms for biological control of plant disease. Currently, there are three commercial formulations of pseudomonads registered with the U.S. Environmental Protection Agency for plant disease suppression, Bio-Save 10 LP, Bio-Save 11 LP, and BlightBan A506. Bio-Save 10 LP and Bio-Save 11 LP, products of Jet Harvest Solutions, Longwood, FL, contain Pseudomonas syringae strains ESC-10 and ESC-11, respectively. These products are applied in packinghouses to prevent postharvest fungal diseases during storage of citrus, pome, stone fruits, and potatoes. BlightBan A506, produced by NuFarm Americas, Burr Ridge, IL, contains P. fluorescens strain A506. BlightBan A506 is applied primarily to pear and apple trees during bloom to suppress the bacterial disease fire blight. Combining BlightBan A506 with the antibiotic streptomycin improves control of fire blight, even in areas with streptomycin-resistant populations of the pathogen. BlightBan A506 also may reduce fruit russet and mild frost injury. These biocontrol products consisting of Pseudomonas spp. provide moderate to excellent efficacy against multiple production constraints, are relatively easy to apply, and they can be integrated with conventional products for disease control. These characteristics will contribute to the adoption of these products by growers and packinghouses.

  9. Adhesion of Pseudomonas fluorescens onto nanophase materials

    NASA Astrophysics Data System (ADS)

    Webster, Thomas J.; Tong, Zonghua; Liu, Jin; Banks, M. Katherine

    2005-07-01

    Nanobiotechnology is a growing area of research, primarily due to the potentially numerous applications of new synthetic nanomaterials in engineering/science. Although various definitions have been given for the word 'nanomaterials' by many different experts, the commonly accepted one refers to nanomaterials as those materials which possess grains, particles, fibres, or other constituent components that have one dimension specifically less than 100 nm. In biological applications, most of the research to date has focused on the interactions between mammalian cells and synthetic nanophase surfaces for the creation of better tissue engineering materials. Although mammalian cells have shown a definite positive response to nanophase materials, information on bacterial interactions with nanophase materials remains elusive. For this reason, this study was designed to assess the adhesion of Pseudomonas fluorescens on nanophase compared to conventional grain size alumina substrates. Results provide the first evidence of increased adhesion of Pseudomonas fluorescens on alumina with nanometre compared to conventional grain sizes. To understand more about the process, polymer (specifically, poly-lactic-co-glycolic acid or PLGA) casts were made of the conventional and nanostructured alumina surfaces. Results showed similar increased Pseudomonas fluorescens capture on PLGA casts of nanostructured compared to conventional alumina as on the alumina itself. For these reasons, a key material property shown to enhance bacterial adhesion was elucidated in this study for both polymers and ceramics: nanostructured surface features.

  10. Pseudomonas biofilm matrix composition and niche biology

    PubMed Central

    Mann, Ethan E.; Wozniak, Daniel J.

    2014-01-01

    Biofilms are a predominant form of growth for bacteria in the environment and in the clinic. Critical for biofilm development are adherence, proliferation, and dispersion phases. Each of these stages includes reinforcement by, or modulation of, the extracellular matrix. Pseudomonas aeruginosa has been a model organism for the study of biofilm formation. Additionally, other Pseudomonas species utilize biofilm formation during plant colonization and environmental persistence. Pseudomonads produce several biofilm matrix molecules, including polysaccharides, nucleic acids, and proteins. Accessory matrix components shown to aid biofilm formation and adaptability under varying conditions are also produced by pseudomonads. Adaptation facilitated by biofilm formation allows for selection of genetic variants with unique and distinguishable colony morphology. Examples include rugose small-colony variants and wrinkly spreaders (WS), which over produce Psl/Pel or cellulose, respectively, and mucoid bacteria that over produce alginate. The well-documented emergence of these variants suggests that pseudomonads take advantage of matrix-building subpopulations conferring specific benefits for the entire population. This review will focus on various polysaccharides as well as additional Pseudomonas biofilm matrix components. Discussions will center on structure–function relationships, regulation, and the role of individual matrix molecules in niche biology. PMID:22212072

  11. Using Pseudomonas spp. for Integrated Biological Control.

    PubMed

    Stockwell, Virginia O; Stack, James P

    2007-02-01

    ABSTRACT Pseudomonas spp. have been studied for decades as model organisms for biological control of plant disease. Currently, there are three commercial formulations of pseudomonads registered with the U.S. Environmental Protection Agency for plant disease suppression, Bio-Save 10 LP, Bio-Save 11 LP, and BlightBan A506. Bio-Save 10 LP and Bio-Save 11 LP, products of Jet Harvest Solutions, Longwood, FL, contain Pseudomonas syringae strains ESC-10 and ESC-11, respectively. These products are applied in packinghouses to prevent postharvest fungal diseases during storage of citrus, pome, stone fruits, and potatoes. BlightBan A506, produced by NuFarm Americas, Burr Ridge, IL, contains P. fluorescens strain A506. BlightBan A506 is applied primarily to pear and apple trees during bloom to suppress the bacterial disease fire blight. Combining BlightBan A506 with the antibiotic streptomycin improves control of fire blight, even in areas with streptomycin-resistant populations of the pathogen. BlightBan A506 also may reduce fruit russet and mild frost injury. These biocontrol products consisting of Pseudomonas spp. provide moderate to excellent efficacy against multiple production constraints, are relatively easy to apply, and they can be integrated with conventional products for disease control. These characteristics will contribute to the adoption of these products by growers and packinghouses. PMID:18944382

  12. Pseudomonas putida Stimulates Primordia on Agaricus bitorquis.

    PubMed

    Colauto, Nelson B; Fermor, Terry R; Eira, Augusto F; Linde, Giani A

    2016-04-01

    Casing layer is one step of Agaricus bisporus cultivation where there is a competitive environment with a high number of microorganisms and diversity interacting with mycelia. It is suggested that a minimal community of these microorganisms would be necessary to stimulate fructification. However, A. bisporus is not able to produce primordia in sterile casing layers or Petri dishes. Thus, the objective of this study was to characterize bacterial microbiota of casing layers from A. bisporus cultivation, isolate, identify and characterize the bacteria responsible for the stimulation of primordium and their action mechanism using Agaricus bitorquis as a primordium stimulation model. Bacterial and Pseudomonas spp. communities of different casing layers of A. bisporus cultivation were collected and quantified. It was concluded that Pseudomonas spp. corresponds to 75-85% of bacterial population of the casing layers in A. bisporus cultivation and among those 12% are Pseudomonas putida. Four biochemical assays were used to identify P. putida. In vitro primordium stimulation of living P. putida and non-living bacterial suspensions, after chemical or physical treatments, was tested using A. bitorquis as a primordium stimulation model. Primordium stimulation assay was registered by photographs, and micrographs of vertical cut of primordium were registered by scanning electron microscope. Interaction of living P. putida with A. bitorquis mycelia is capable of stimulating primordial instead of non-living bacterial suspensions. Stimulation of A. bitorquis primordia does not imply or is related to mycelial growth inhibition, but a hierarchical relation of primordium succession and development is suggested. PMID:26742772

  13. Adhesion of Pseudomonas fluorescens onto nanophase materials.

    PubMed

    Webster, Thomas J; Tong, Zonghua; Liu, Jin; Katherine Banks, M

    2005-07-01

    Nanobiotechnology is a growing area of research, primarily due to the potentially numerous applications of new synthetic nanomaterials in engineering/science. Although various definitions have been given for the word 'nanomaterials' by many different experts, the commonly accepted one refers to nanomaterials as those materials which possess grains, particles, fibres, or other constituent components that have one dimension specifically less than 100 nm. In biological applications, most of the research to date has focused on the interactions between mammalian cells and synthetic nanophase surfaces for the creation of better tissue engineering materials. Although mammalian cells have shown a definite positive response to nanophase materials, information on bacterial interactions with nanophase materials remains elusive. For this reason, this study was designed to assess the adhesion of Pseudomonas fluorescens on nanophase compared to conventional grain size alumina substrates. Results provide the first evidence of increased adhesion of Pseudomonas fluorescens on alumina with nanometre compared to conventional grain sizes. To understand more about the process, polymer (specifically, poly-lactic-co-glycolic acid or PLGA) casts were made of the conventional and nanostructured alumina surfaces. Results showed similar increased Pseudomonas fluorescens capture on PLGA casts of nanostructured compared to conventional alumina as on the alumina itself. For these reasons, a key material property shown to enhance bacterial adhesion was elucidated in this study for both polymers and ceramics: nanostructured surface features.

  14. Revised structures of the pyoverdins from Pseudomonas putida CFBP 2461 and from Pseudomonas fluorescens CFBP 2392.

    PubMed

    Beiderbeck, H; Taraz, K; Meyer, J M

    1999-12-01

    Several suggestions for structures of the siderophores (pyoverdins) from Pseudomonas spp. can be found in the literature which are based on a FAB mass spectrometric analysis only. Availability of two original strains of two Pseudomonas spp. allowed to re-investigate the structure of their pyoverdins. In both cases the amino acid sequence had to be corrected. In addition, D- and L-amino acids could be identified and located in the peptide chain. The knowledge of the correct structures is important in view of an ongoing study to establish relationships between the nature of the peptide chains of pyoverdins and their recognition by outer membrane proteins. PMID:10816733

  15. Beneficial Insect Borders Provide Northern Bobwhite Brood Habitat

    PubMed Central

    Moorman, Christopher E.; Plush, Charles J.; Orr, David B.; Reberg-Horton, Chris

    2013-01-01

    Strips of fallow vegetation along cropland borders are an effective strategy for providing brood habitat for declining populations of upland game birds (Order: Galliformes), including northern bobwhite (Colinus virginianus), but fallow borders lack nectar-producing vegetation needed to sustain many beneficial insect populations (e.g., crop pest predators, parasitoids, and pollinator species). Planted borders that contain mixes of prairie flowers and grasses are designed to harbor more diverse arthropod communities, but the relative value of these borders as brood habitat is unknown. We used groups of six human-imprinted northern bobwhite chicks as a bioassay for comparing four different border treatments (planted native grass and prairie flowers, planted prairie flowers only, fallow vegetation, or mowed vegetation) as northern bobwhite brood habitat from June-August 2009 and 2010. All field border treatments were established around nine organic crop fields. Groups of chicks were led through borders for 30-min foraging trials and immediately euthanized, and eaten arthropods in crops and gizzards were measured to calculate a foraging rate for each border treatment. We estimated arthropod prey availability within each border treatment using a modified blower-vac to sample arthropods at the vegetation strata where chicks foraged. Foraging rate did not differ among border treatments in 2009 or 2010. Total arthropod prey densities calculated from blower-vac samples did not differ among border treatments in 2009 or 2010. Our results showed plant communities established to attract beneficial insects should maximize the biodiversity potential of field border establishment by providing habitat for beneficial insects and young upland game birds. PMID:24376759

  16. Beneficial insect borders provide northern bobwhite brood habitat.

    PubMed

    Moorman, Christopher E; Plush, Charles J; Orr, David B; Reberg-Horton, Chris

    2013-01-01

    Strips of fallow vegetation along cropland borders are an effective strategy for providing brood habitat for declining populations of upland game birds (Order: Galliformes), including northern bobwhite (Colinus virginianus), but fallow borders lack nectar-producing vegetation needed to sustain many beneficial insect populations (e.g., crop pest predators, parasitoids, and pollinator species). Planted borders that contain mixes of prairie flowers and grasses are designed to harbor more diverse arthropod communities, but the relative value of these borders as brood habitat is unknown. We used groups of six human-imprinted northern bobwhite chicks as a bioassay for comparing four different border treatments (planted native grass and prairie flowers, planted prairie flowers only, fallow vegetation, or mowed vegetation) as northern bobwhite brood habitat from June-August 2009 and 2010. All field border treatments were established around nine organic crop fields. Groups of chicks were led through borders for 30-min foraging trials and immediately euthanized, and eaten arthropods in crops and gizzards were measured to calculate a foraging rate for each border treatment. We estimated arthropod prey availability within each border treatment using a modified blower-vac to sample arthropods at the vegetation strata where chicks foraged. Foraging rate did not differ among border treatments in 2009 or 2010. Total arthropod prey densities calculated from blower-vac samples did not differ among border treatments in 2009 or 2010. Our results showed plant communities established to attract beneficial insects should maximize the biodiversity potential of field border establishment by providing habitat for beneficial insects and young upland game birds. PMID:24376759

  17. Conditioning of carbonaceous material prior to physical beneficiation

    DOEpatents

    Warzinski, Robert P.; Ruether, John A.

    1987-01-01

    A carbonaceous material such as coal is conditioned by contact with a supercritical fluid prior to physical beneficiation. The solid feed material is contacted with an organic supercritical fluid such as cyclohexane or methanol at temperatures slightly above the critical temperature and pressures of 1 to 4 times the critical pressure. A minor solute fraction is extracted into critical phase and separated from the solid residuum. The residuum is then processed by physical separation such as by froth flotation or specific gravity separation to recover a substantial fraction thereof with reduced ash content. The solute in supercritical phase can be released by pressure reduction and recombined with the low-ash, carbonaceous material.

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

    PubMed

    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. PMID:27594974

  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.

    PubMed

    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. How to assemble a beneficial microbiome in three easy steps.

    PubMed

    Scheuring, István; Yu, Douglas W

    2012-11-01

    There is great interest in explaining how beneficial microbiomes are assembled. Antibiotic-producing microbiomes are arguably the most abundant class of beneficial microbiome in nature, having been found on corals, arthropods, molluscs, vertebrates and plant rhizospheres. An exemplar is the attine ants, which cultivate a fungus for food and host a cuticular microbiome that releases antibiotics to defend the fungus from parasites. One explanation posits long-term vertical transmission of Pseudonocardia bacteria, which (somehow) evolve new compounds in arms-race fashion against parasites. Alternatively, attines (somehow) selectively recruit multiple, non-coevolved actinobacterial genera from the soil, enabling a 'multi-drug' strategy against parasites. We reconcile the models by showing that when hosts fuel interference competition by providing abundant resources, the interference competition favours the recruitment of antibiotic-producing (and -resistant) bacteria. This partner-choice mechanism is more effective when at least one actinobacterial symbiont is vertically transmitted or has a high immigration rate, as in disease-suppressive soils.

  1. Probiotics and their fermented food products are beneficial for health.

    PubMed

    Parvez, S; Malik, K A; Ah Kang, S; Kim, H-Y

    2006-06-01

    Probiotics are usually defined as microbial food supplements with beneficial effects on the consumers. Most probiotics fall into the group of organisms' known as lactic acid-producing bacteria and are normally consumed in the form of yogurt, fermented milks or other fermented foods. Some of the beneficial effect of lactic acid bacteria consumption include: (i) improving intestinal tract health; (ii) enhancing the immune system, synthesizing and enhancing the bioavailability of nutrients; (iii) reducing symptoms of lactose intolerance, decreasing the prevalence of allergy in susceptible individuals; and (iv) reducing risk of certain cancers. The mechanisms by which probiotics exert their effects are largely unknown, but may involve modifying gut pH, antagonizing pathogens through production of antimicrobial compounds, competing for pathogen binding and receptor sites as well as for available nutrients and growth factors, stimulating immunomodulatory cells, and producing lactase. Selection criteria, efficacy, food and supplement sources and safety issues around probiotics are reviewed. Recent scientific investigation has supported the important role of probiotics as a part of a healthy diet for human as well as for animals and may be an avenue to provide a safe, cost effective, and 'natural' approach that adds a barrier against microbial infection. This paper presents a review of probiotics in health maintenance and disease prevention.

  2. Characterization and Beneficiation Studies of a Low Grade Bauxite Ore

    NASA Astrophysics Data System (ADS)

    Rao, D. S.; Das, B.

    2014-10-01

    A low grade bauxite sample of central India was thoroughly characterized with the help of stereomicroscope, reflected light microscope and electron microscope using QEMSCAN. A few hand picked samples were collected from different places of the mine and were subjected to geochemical characterization studies. The geochemical studies indicated that most of the samples contain high silica and low alumina, except a few which are high grade. Mineralogically the samples consist of bauxite (gibbsite and boehmite), ferruginous mineral phases (goethite and hematite), clay and silicate (quartz), and titanium bearing minerals like rutile and ilmenite. Majority of the gibbsite, boehmite and gibbsitic oolites contain clay, quartz and iron and titanium mineral phases within the sample as inclusions. The sample on an average contains 39.1 % Al2O3 and 12.3 % SiO2, and 20.08 % of Fe2O3. Beneficiation techniques like size classification, sorting, scrubbing, hydrocyclone and magnetic separation were employed to reduce the silica content suitable for Bayer process. The studies indicated that, 50 % by weight with 41 % Al2O3 containing less than 5 % SiO2 could be achieved. The finer sized sample after physical beneficiation still contains high silica due to complex mineralogical associations.

  3. Identifying Beneficial Qualities of Trichoderma parareesei for Plants

    PubMed Central

    Rubio, M. Belén; Quijada, Narciso M.; Pérez, Esclaudys; Domínguez, Sara; Hermosa, Rosa

    2014-01-01

    Trichoderma parareesei and Trichoderma reesei (teleomorph Hypocrea jecorina) produce cellulases and xylanases of industrial interest. Here, the anamorphic strain T6 (formerly T. reesei) has been identified as T. parareesei, showing biocontrol potential against fungal and oomycete phytopathogens and enhanced hyphal growth in the presence of tomato exudates or plant cell wall polymers in in vitro assays. A Trichoderma microarray was used to examine the transcriptomic changes in T6 at 20 h of interaction with tomato plants. Out of a total 34,138 Trichoderma probe sets deposited on the microarray, 250 showed a significant change of at least 2-fold in expression in the presence of tomato plants, with most of them being downregulated. T. parareesei T6 exerted beneficial effects on tomato plants in terms of seedling lateral root development, and in adult plants it improved defense against Botrytis cinerea and growth promotion under salt stress. Time course expression patterns (0 to 6 days) observed for defense-related genes suggest that T6 was able to prime defense responses in the tomato plants against biotic and abiotic stresses. Such responses undulated, with a maximum upregulation of the jasmonic acid (JA)/ethylene (ET)-related LOX1 and EIN2 genes and the salt tolerance SOS1 gene at 24 h and that of the salicylic acid (SA)-related PR-1 gene at 48 h after T6 inoculation. Our study demonstrates that the T. parareesei T6-tomato interaction is beneficial to both partners. PMID:24413597

  4. Identifying beneficial qualities of Trichoderma parareesei for plants.

    PubMed

    Rubio, M Belén; Quijada, Narciso M; Pérez, Esclaudys; Domínguez, Sara; Monte, Enrique; Hermosa, Rosa

    2014-03-01

    Trichoderma parareesei and Trichoderma reesei (teleomorph Hypocrea jecorina) produce cellulases and xylanases of industrial interest. Here, the anamorphic strain T6 (formerly T. reesei) has been identified as T. parareesei, showing biocontrol potential against fungal and oomycete phytopathogens and enhanced hyphal growth in the presence of tomato exudates or plant cell wall polymers in in vitro assays. A Trichoderma microarray was used to examine the transcriptomic changes in T6 at 20 h of interaction with tomato plants. Out of a total 34,138 Trichoderma probe sets deposited on the microarray, 250 showed a significant change of at least 2-fold in expression in the presence of tomato plants, with most of them being downregulated. T. parareesei T6 exerted beneficial effects on tomato plants in terms of seedling lateral root development, and in adult plants it improved defense against Botrytis cinerea and growth promotion under salt stress. Time course expression patterns (0 to 6 days) observed for defense-related genes suggest that T6 was able to prime defense responses in the tomato plants against biotic and abiotic stresses. Such responses undulated, with a maximum upregulation of the jasmonic acid (JA)/ethylene (ET)-related LOX1 and EIN2 genes and the salt tolerance SOS1 gene at 24 h and that of the salicylic acid (SA)-related PR-1 gene at 48 h after T6 inoculation. Our study demonstrates that the T. parareesei T6-tomato interaction is beneficial to both partners.

  5. Beneficial effect of sesame oil on heavy metal toxicity.

    PubMed

    Chandrasekaran, Victor Raj Mohan; Hsu, Dur-Zong; Liu, Ming-Yie

    2014-02-01

    Heavy metals become toxic when they are not metabolized by the body and accumulate in the soft tissue. Chelation therapy is mainly for the management of heavy metal-induced toxicity; however, it usually causes adverse effects or completely blocks the vital function of the particular metal chelated. Much attention has been paid to the development of chelating agents from natural sources to counteract lead- and iron-induced hepatic and renal damage. Sesame oil (a natural edible oil) and sesamol (an active antioxidant) are potently beneficial for treating lead- and iron-induced hepatic and renal toxicity and have no adverse effects. Sesame oil and sesamol significantly inhibit iron-induced lipid peroxidation by inhibiting the xanthine oxidase, nitric oxide, superoxide anion, and hydroxyl radical generation. In addition, sesame oil is a potent inhibitor of proinflammatory mediators, and it attenuates lead-induced hepatic damage by inhibiting nitric oxide, tumor necrosis factor-α, and interleukin-1β levels. Because metal chelating therapy is associated with adverse effects, treating heavy metal toxicity in addition with sesame oil and sesamol may be better alternatives. This review deals with the possible use and beneficial effects of sesame oil and sesamol during heavy metal toxicity treatment. PMID:23744838

  6. DECONTAMINATING AND PROCESSING DREDGED MATERIAL FOR BENEFICIAL USE

    SciTech Connect

    CLESCERI,N.L.; STERN,E.A.; FENG,H.; JONES,K.W.

    2000-07-01

    Management of contaminated dredged material is a major problem in the Port of New York and New Jersey. One component of an overall management plan can be the application of a decontamination technology followed by creation of a product suitable for beneficial use. This concept is the focus of a project now being carried out by the US Environmental Protection Agency-Region 2, the US Army Corps of Engineers-New York District, the US Department of Energy-Brookhaven National Laboratory, and regional university groups that have included Rensselaer Polytechnic Institute, Rutgers University, New Jersey Institute of Technology, and Stevens Institute of Technology. The project has gone through phased testing of commercial technologies at the bench scale (15 liters) and pilot scale (1.5--500 m{sup 3}) levels. Several technologies are now going forward to large-scale demonstrations that are intended to treat from 23,000 to 60,000 m{sup 3}. Selections of the technologies were made based on the effectiveness of the treatment process, evaluation of the possible beneficial use of the treated materials, and other factors. Major elements of the project are summarized here.

  7. [Alcohol--when it's beneficial to your health?].

    PubMed

    Zdrojewicz, Zygmumt; Pypno, Damian; Bugaj, Bartosz; Cabała, Krzysztof

    2015-12-01

    Ethyl alcohol is the most commonly used psychoactive agent. It's average consumption in Poland totaled 9.67 liters per capita in 2013. Ethanol's biotransformation rate in an adult ranges from 7 to 10 grams per hour. The basic metabolism takes place in the liver through the oxidation involving NAD+. The alcohol is transformed first into acetaldehyde and then into acetic acid. In higher blood concentrations or in alcoholism, cytochrome's P-450 coenzyme CYP2E1 also plays an important role in this process. Alcohol is responsible for nearly 50% of annual deaths, mostly caused by an accident due to alcohol intoxication while driving. Studies were performed to determine the influence ethanol has on the human body and how it impacts the progression of illnesses such as senile dementia, cardiovascular diseases or osteoporosis. Scientists' attention was drawn to the possibility of ethyl alcohol's usage resulting in a reduction in an overall mortality rate, however the beneficial effects were observed only during a slight and moderate consumption. Higher doses of alcohol were associated with a decline in patient's condition. The purpose of this dissertation is an attempt to answer the question, whether the alcohol can be beneficial to the user's health and if so, in what doses? The importance of this topic comes from the fact that due to the alcohol being widely available, determining the influence it has on human body is vital for public health. Original articles and reviews were used to summarize the results of studies regarding the topic.

  8. Siderotyping of fluorescent pseudomonads: characterization of pyoverdines of Pseudomonas fluorescens and Pseudomonas putida strains from Antarctica.

    PubMed

    Meyer, J M; Stintzi, A; Coulanges, V; Shivaji, S; Voss, J A; Taraz, K; Budzikiewicz, H

    1998-11-01

    Five independent fluorescent pseudomonad isolates originating from Antarctica were analysed for their pyoverdine systems. A pyoverdine-related siderotyping, which involved pyoverdine-induced growth stimulation, pyoverdine-mediated iron uptake, pyoverdine analysis by electrophoresis and isoelectric focusing, revealed three different pyoverdine-related siderotypes among the five isolates. One siderotype, including Pseudomonas fluorescens 1W and P. fluorescens 10CW, was identical to that of P. fluorescens ATCC 13525. Two other strains, P. fluorescens 9AW and Pseudomonas putida 9BW, showed identical pyoverdine-related behaviour to each other, whereas the fifth strain, P. fluorescens 51W, had unique features compared to the other strains or to a set of 12 fluorescent Pseudomonas strains used as comparison material. Elucidation of the structure of the pyoverdines produced by the Antarctic strains supported the accuracy of the siderotyping methodology by confirming that pyoverdines from strains 1W and 10CW had the same structures as the P. fluorescens ATCC 13525 pyoverdine, whereas the 9AW and 9BW pyoverdines are probably identical with the pyoverdine of P. fluorescens strain 244. Pyoverdine from strain 51W appeared to be a novel pyoverdine since its structure was different from all previously established pyoverdine structures. Together with the conclusion that the Antarctic Pseudomonas strains have no special features at the level of their pyoverdines and pyoverdine-mediated iron metabolism compared to worldwide strains, the present work demonstrates that siderotyping provides a rapid means of screening for novel pyoverdines. PMID:9846748

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

    PubMed Central

    Michalska, Marta; Wolf, Philipp

    2015-01-01

    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. PMID:26441897

  10. Genetic Detection of Pseudomonas spp. in Commercial Amazonian Fish

    PubMed Central

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

    2013-01-01

    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. PMID:24065035

  11. A pyoverdin from Pseudomonas sp. CFML 95-275.

    PubMed

    Sultana, R; Fuchs, R; Schmickler, H; Schlegel, K; Budzikiewicz, H; Siddiqui, B S; Geoffrey, V; Meyer, J M

    2000-01-01

    From Pseudomonas sp. CFML 95-275 a pyoverdin was isolated with a cyclopeptidic substructure. It could be shown that this pyoverdin is identical with one obtained from Pseudomonas fluorescens BTP 7 for which a lactone structure had been deduced from the interpretation of a FAB spectrum. The elucidation of the correct structure of the pyoverdin is described. PMID:11204185

  12. Recombineering using RecET from Pseudomonas syringae

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Here we report the identification of functions that promote genomic recombination of linear DNA introduced into Pseudomonas cells by electroporation. The genes encoding these functions were identified in Pseudomonas syringae pv. syringae B728a based on similarity to the lambda Red Exo/Beta and RecE...

  13. Role of porins in intrinsic antibiotic resistance of Pseudomonas cepacia.

    PubMed Central

    Parr, T R; Moore, R A; Moore, L V; Hancock, R E

    1987-01-01

    The measured outer membrane permeability of Pseudomonas cepacia to the beta-lactam nitrocefin was low: approximately 10 times less than that of Escherichia coli and comparable to that of Pseudomonas aeruginosa. The purified P. cepacia porin demonstrated an average single channel conductance in 1 M KCl of 0.23 nS. Images PMID:3032087

  14. Ornicorrugatin, a new siderophore from Pseudomonas fluorescens AF76.

    PubMed

    Matthijs, Sandra; Budzikiewicz, Herbert; Schäfer, Mathias; Wathelet, Bernard; Cornelis, Pierre

    2008-01-01

    From a pyoverdin-negative mutant of Pseudomonas fluorescens AF76 a new lipopeptidic siderophore (ornicorrugatin) could be isolated. It is structurally related to the siderophore of Pseudomonas corrugata differing in the replacement of one Dab unit by Orn. PMID:18386480

  15. The Gac Regulon of Pseudomonas fluorescens SBW25

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Transcriptome analysis of Pseudomonas fluorescens SBW25 showed that 702 genes were differentially regulated (FC>4, P<0.0001) in a gacS::Tn5 mutant, with 300 and 402 genes up- and down-regulated, respectively. Similar to the Gac-regulon of four other Pseudomonas species, genes involved in motility, b...

  16. Massetolide A biosynthesis in Pseudomonas fluorescens.

    PubMed

    de Bruijn, I; de Kock, M J D; de Waard, P; van Beek, T A; Raaijmakers, J M

    2008-04-01

    Massetolide A is a cyclic lipopeptide (CLP) antibiotic produced by various Pseudomonas strains from diverse environments. Cloning, sequencing, site-directed mutagenesis, and complementation showed that massetolide A biosynthesis in P. fluorescens SS101 is governed by three nonribosomal peptide synthetase (NRPS) genes, designated massA, massB, and massC, spanning approximately 30 kb. Prediction of the nature and configuration of the amino acids by in silico analysis of adenylation and condensation domains of the NRPSs was consistent with the chemically determined structure of the peptide moiety of massetolide A. Structural analysis of massetolide A derivatives produced by SS101 indicated that most of the variations in the peptide moiety occur at amino acid positions 4 and 9. Regions flanking the mass genes contained several genes found in other Pseudomonas CLP biosynthesis clusters, which encode LuxR-type transcriptional regulators, ABC transporters, and an RND-like outer membrane protein. In contrast to most Pseudomonas CLP gene clusters known to date, the mass genes are not physically linked but are organized in two separate clusters, with massA disconnected from massB and massC. Quantitative real-time PCR analysis indicated that transcription of massC is strongly reduced when massB is mutated, suggesting that these two genes function in an operon, whereas transcription of massA is independent of massBC and vice versa. Massetolide A is produced in the early exponential growth phase, and biosynthesis appears not to be regulated by N-acylhomoserine lactone-based quorum sensing. Massetolide A production is essential in swarming motility of P. fluorescens SS101 and plays an important role in biofilm formation.

  17. Massetolide A Biosynthesis in Pseudomonas fluorescens▿

    PubMed Central

    de Bruijn, I.; de Kock, M. J. D.; de Waard, P.; van Beek, T. A.; Raaijmakers, J. M.

    2008-01-01

    Massetolide A is a cyclic lipopeptide (CLP) antibiotic produced by various Pseudomonas strains from diverse environments. Cloning, sequencing, site-directed mutagenesis, and complementation showed that massetolide A biosynthesis in P. fluorescens SS101 is governed by three nonribosomal peptide synthetase (NRPS) genes, designated massA, massB, and massC, spanning approximately 30 kb. Prediction of the nature and configuration of the amino acids by in silico analysis of adenylation and condensation domains of the NRPSs was consistent with the chemically determined structure of the peptide moiety of massetolide A. Structural analysis of massetolide A derivatives produced by SS101 indicated that most of the variations in the peptide moiety occur at amino acid positions 4 and 9. Regions flanking the mass genes contained several genes found in other Pseudomonas CLP biosynthesis clusters, which encode LuxR-type transcriptional regulators, ABC transporters, and an RND-like outer membrane protein. In contrast to most Pseudomonas CLP gene clusters known to date, the mass genes are not physically linked but are organized in two separate clusters, with massA disconnected from massB and massC. Quantitative real-time PCR analysis indicated that transcription of massC is strongly reduced when massB is mutated, suggesting that these two genes function in an operon, whereas transcription of massA is independent of massBC and vice versa. Massetolide A is produced in the early exponential growth phase, and biosynthesis appears not to be regulated by N-acylhomoserine lactone-based quorum sensing. Massetolide A production is essential in swarming motility of P. fluorescens SS101 and plays an important role in biofilm formation. PMID:17993540

  18. The Pseudomonas aeruginosa Proteome during Anaerobic Growth‡

    PubMed Central

    Wu, Manhong; Guina, Tina; Brittnacher, Mitchell; Nguyen, Hai; Eng, Jimmy; Miller, Samuel I.

    2005-01-01

    Isotope-coded affinity tag analysis and two-dimensional gel electrophoresis followed by tandem mass spectrometry were used to identify Pseudomonas aeruginosa proteins expressed during anaerobic growth. Out of the 617 proteins identified, 158 were changed in abundance during anaerobic growth compared to during aerobic growth, including proteins whose increased expression was expected based on their role in anaerobic metabolism. These results form the basis for future analyses of alterations in bacterial protein content during growth in various environments, including the cystic fibrosis airway. PMID:16291692

  19. Siderotyping of Antarctic fluorescent Pseudomonas strains.

    PubMed

    Geoffroy, V A; Meyer, J M

    2004-07-01

    Five fluorescent Pseudomonas strains isolated from Antarctica have been previously recognized as producing three structurally different pyoverdines. In the present work, siderotyping procedures have been used to classify these strains, together with 1282 isolates of different origins, into siderovars. The strain biodiversity encountered within each siderovar, as well as the potential taxonomic value of the siderovars, are described and discussed. It is concluded that a majority of antarctic strains are commonly distributed worldwide. One strain, however, presenting a particular pyoverdine structure found in a unique other isolate, was apparently much more specific to cold environment. PMID:15559975

  20. Spices: the savory and beneficial science of pungency.

    PubMed

    Nilius, Bernd; Appendino, Giovanni

    2013-01-01

    Spicy food does not only provide an important hedonic input in daily life, but has also been anedoctically associated to beneficial effects on our health. In this context, the discovery of chemesthetic trigeminal receptors and their spicy ligands has provided the mechanistic basis and the pharmacological means to investigate this enticing possibility. This review discusses in molecular terms the connection between the neurophysiology of pungent spices and the "systemic" effects associated to their trigeminality. It commences with a cultural and historical overview on the Western fascination for spices, and, after analysing in detail the mechanisms underlying the trigeminality of food, the main dietary players from the transient receptor potential (TRP) family of cation channels are introduced, also discussing the "alien" distribution of taste receptors outside the oro-pharingeal cavity. The modulation of TRPV1 and TRPA1 by spices is next described, discussing how spicy sensations can be turned into hedonic pungency, and analyzing the mechanistic bases for the health benefits that have been associated to the consumption of spices. These include, in addition to a beneficial modulation of gastro-intestinal and cardio-vascular function, slimming, the optimization of skeletal muscle performance, the reduction of chronic inflammation, and the prevention of metabolic syndrome and diabetes. We conclude by reviewing the role of electrophilic spice constituents on cancer prevention in the light of their action on pro-inflammatory and pro-cancerogenic nuclear factors like NFκB, and on their interaction with the electrophile sensor protein Keap1 and the ensuing Nrf2-mediated transcriptional activity. Spicy compounds have a complex polypharmacology, and just like any other bioactive agent, show a balance of beneficial and bad actions. However, at least for moderate consumption, the balance seems definitely in favour of the positive side, suggesting that a spicy diet, a caveman

  1. Comparative proteomic analysis in pea treated with microbial consortia of beneficial microbes reveals changes in the protein network to enhance resistance against Sclerotinia sclerotiorum.

    PubMed

    Jain, Akansha; Singh, Akanksha; Singh, Surendra; Singh, Vinay; Singh, Harikesh Bahadur

    2015-06-15

    Microbial consortia may provide protection against pathogenic ingress via enhancing plant defense responses. Pseudomonas aeruginosa PJHU15, Trichoderma harzianum TNHU27 and Bacillus subtilis BHHU100 were used either singly or in consortia in the pea rhizosphere to observe proteome level changes upon Sclerotinia sclerotiorum challenge. Thirty proteins were found to increase or decrease differentially in 2-DE gels of pea leaves, out of which 25 were identified by MALDI-TOF MS or MS/MS. These proteins were classified into several functional categories including photosynthesis, respiration, phenylpropanoid metabolism, protein synthesis, stress regulation, carbohydrate and nitrogen metabolism and disease/defense-related processes. The respective homologue of each protein identified was trapped in Pisum sativum and a phylogenetic tree was constructed to check the ancestry. The proteomic view of the defense response to S. sclerotiorum in pea, in the presence of beneficial microbes, highlights the enhanced protection that can be provided by these microbes in challenged plants.

  2. Comparative proteomic analysis in pea treated with microbial consortia of beneficial microbes reveals changes in the protein network to enhance resistance against Sclerotinia sclerotiorum.

    PubMed

    Jain, Akansha; Singh, Akanksha; Singh, Surendra; Singh, Vinay; Singh, Harikesh Bahadur

    2015-06-15

    Microbial consortia may provide protection against pathogenic ingress via enhancing plant defense responses. Pseudomonas aeruginosa PJHU15, Trichoderma harzianum TNHU27 and Bacillus subtilis BHHU100 were used either singly or in consortia in the pea rhizosphere to observe proteome level changes upon Sclerotinia sclerotiorum challenge. Thirty proteins were found to increase or decrease differentially in 2-DE gels of pea leaves, out of which 25 were identified by MALDI-TOF MS or MS/MS. These proteins were classified into several functional categories including photosynthesis, respiration, phenylpropanoid metabolism, protein synthesis, stress regulation, carbohydrate and nitrogen metabolism and disease/defense-related processes. The respective homologue of each protein identified was trapped in Pisum sativum and a phylogenetic tree was constructed to check the ancestry. The proteomic view of the defense response to S. sclerotiorum in pea, in the presence of beneficial microbes, highlights the enhanced protection that can be provided by these microbes in challenged plants. PMID:26067380

  3. Genome survey and characterization of endophytic bacteria exhibiting a beneficial effect on growth and development of poplar trees.

    PubMed

    Taghavi, Safiyh; Garafola, Craig; Monchy, Sébastien; Newman, Lee; Hoffman, Adam; Weyens, Nele; Barac, Tanja; Vangronsveld, Jaco; van der Lelie, Daniel

    2009-02-01

    The association of endophytic bacteria with their plant hosts has a beneficial effect for many different plant species. Our goal is to identify endophytic bacteria that improve the biomass production and the carbon sequestration potential of poplar trees (Populus spp.) when grown in marginal soil and to gain an insight in the mechanisms underlying plant growth promotion. Members of the Gammaproteobacteria dominated a collection of 78 bacterial endophytes isolated from poplar and willow trees. As representatives for the dominant genera of endophytic gammaproteobacteria, we selected Enterobacter sp. strain 638, Stenotrophomonas maltophilia R551-3, Pseudomonas putida W619, and Serratia proteamaculans 568 for genome sequencing and analysis of their plant growth-promoting effects, including root development. Derivatives of these endophytes, labeled with gfp, were also used to study the colonization of their poplar hosts. In greenhouse studies, poplar cuttings (Populus deltoides x Populus nigra DN-34) inoculated with Enterobacter sp. strain 638 repeatedly showed the highest increase in biomass production compared to cuttings of noninoculated control plants. Sequence data combined with the analysis of their metabolic properties resulted in the identification of many putative mechanisms, including carbon source utilization, that help these endophytes to thrive within a plant environment and to potentially affect the growth and development of their plant hosts. Understanding the interactions between endophytic bacteria and their host plants should ultimately result in the design of strategies for improved poplar biomass production on marginal soils as a feedstock for biofuels.

  4. Genome Survey and Characterization of Endophytic Bacteria Exhibiting a Beneficial Effect on Growth and Development of Poplar Trees ▿ †

    PubMed Central

    Taghavi, Safiyh; Garafola, Craig; Monchy, Sébastien; Newman, Lee; Hoffman, Adam; Weyens, Nele; Barac, Tanja; Vangronsveld, Jaco; van der Lelie, Daniel

    2009-01-01

    The association of endophytic bacteria with their plant hosts has a beneficial effect for many different plant species. Our goal is to identify endophytic bacteria that improve the biomass production and the carbon sequestration potential of poplar trees (Populus spp.) when grown in marginal soil and to gain an insight in the mechanisms underlying plant growth promotion. Members of the Gammaproteobacteria dominated a collection of 78 bacterial endophytes isolated from poplar and willow trees. As representatives for the dominant genera of endophytic gammaproteobacteria, we selected Enterobacter sp. strain 638, Stenotrophomonas maltophilia R551-3, Pseudomonas putida W619, and Serratia proteamaculans 568 for genome sequencing and analysis of their plant growth-promoting effects, including root development. Derivatives of these endophytes, labeled with gfp, were also used to study the colonization of their poplar hosts. In greenhouse studies, poplar cuttings (Populus deltoides × Populus nigra DN-34) inoculated with Enterobacter sp. strain 638 repeatedly showed the highest increase in biomass production compared to cuttings of noninoculated control plants. Sequence data combined with the analysis of their metabolic properties resulted in the identification of many putative mechanisms, including carbon source utilization, that help these endophytes to thrive within a plant environment and to potentially affect the growth and development of their plant hosts. Understanding the interactions between endophytic bacteria and their host plants should ultimately result in the design of strategies for improved poplar biomass production on marginal soils as a feedstock for biofuels. PMID:19060168

  5. Coffee components and cardiovascular risk: beneficial and detrimental effects.

    PubMed

    Godos, Justyna; Pluchinotta, Francesca Romana; Marventano, Stefano; Buscemi, Silvio; Li Volti, Giovanni; Galvano, Fabio; Grosso, Giuseppe

    2014-12-01

    Coffee consists of several biological active compounds, such as caffeine, diterpenes, chlorogenic acids, and melanoidins, which may affect human health. The intake of each compound depends on the variety of coffee species, roasting degree, type of brewing method and serving size. The bioavailability and the distribution of each compound and its metabolites also contribute to coffee mechanisms of action. The health benefits of coffee consumption regarding cardiovascular system and metabolism mostly depend on its antioxidant compounds. In contrast, diterpenes and caffeine may produce harmful effects by raising lipid fraction and affecting endothelial function, respectively. Studying the mechanism of action of coffee components may help understanding weather coffee's impact on health is beneficial or hazardous. In this article, we reviewed the available information about coffee compounds and their mechanism of action. Furthermore, benefits and risks for cardiovascular system associated with coffee consumption will be discussed.

  6. Beneficiation and extraction of nonterrestrial materials, part 2

    NASA Technical Reports Server (NTRS)

    Agosto, William N.

    1992-01-01

    A review of options for processing extraterrestrial materials was dominated by industrial materials scientist who tried to identify which processes utilizing space materials could be implemented in the near term. The most practical process seem to us to be the extraction of lunar oxygen and the extraction of metals and ceramics from the residues of the reduction process. The growth of space activity will be accompanied by increased demand for liquid oxygen for each round trip to the Moon. The oxygen and the intermediary product water will be needed for the life support at the base. The reduced metals and ceramics may be considered byproducts or may develop into primary products. Some of the same processes would be directly applicable to recovery of products from asteroids. We also discussed other processes for directly utilizing asteroid metals. Some of the topics covered include beneficiation and oxygen extraction methods, metallurgy, and extraterrestrial cement.

  7. Plant-beneficial effects of Trichoderma and of its genes.

    PubMed

    Hermosa, Rosa; Viterbo, Ada; Chet, Ilan; Monte, Enrique

    2012-01-01

    Trichoderma (teleomorph Hypocrea) is a fungal genus found in many ecosystems. Trichoderma spp. can reduce the severity of plant diseases by inhibiting plant pathogens in the soil through their highly potent antagonistic and mycoparasitic activity. Moreover, as revealed by research in recent decades, some Trichoderma strains can interact directly with roots, increasing plant growth potential, resistance to disease and tolerance to abiotic stresses. This mini-review summarizes the main findings concerning the Trichoderma-plant interaction, the molecular dialogue between the two organisms, and the dramatic changes induced by the beneficial fungus in the plant. Efforts to enhance plant resistance and tolerance to a broad range of stresses by expressing Trichoderma genes in the plant genome are also addressed.

  8. A beneficial role for IL-1 beta in Alzheimer disease?

    PubMed

    Lemere, Cynthia A

    2007-06-01

    While the term neuroinflammation often conjures up images of cellular damage, mounting evidence suggests that certain proinflammatory molecules, such as the cytokine IL-1 beta, may have beneficial and protective effects. In a report in this issue of the JCI, Shaftel and coworkers have generated an elegant mouse model in which local hippocampal overexpression of IL-1 beta in an Alzheimer disease (AD) transgenic mouse model resulted not in the expected exacerbation of the amyloid beta plaque deposition common to AD, but instead in plaque amelioration (see the related article beginning on page 1595). Thus, manipulation of the immune system may be a potential therapeutic approach to protect against AD, although further studies are needed to understand all of the downstream effects of this manipulation.

  9. Meditation can produce beneficial effects to prevent cardiovascular disease.

    PubMed

    Koike, Marcia Kiyomi; Cardoso, Roberto

    2014-06-01

    Coronary heart disease is the major cause of global cardiovascular mortality and morbidity. Lifestyle behaviour contributes as a risk factor: unhealthy diet, sedentary lifestyle, tobacco, alcohol, hypertension, diabetes, dyslipidemia and psychosocial stress. Atherosclerosis pathologic mechanisms involving oxidative stress, dyslipidemia, inflammation and senescence are associated with arterial wall damage and plaque formation. Stress reduction was observed in several types of meditation. After meditation, hormonal orchestration modulates effects in the central nervous system and in the body. All types of meditation are associated with blood pressure control, enhancement in insulin resistance, reduction of lipid peroxidation and cellular senescence, independent of type of meditation. This review presents scientific evidence to explain how meditation can produce beneficial effects on the cardiovascular system, and particularly regarding vascular aspects.

  10. Acceptance for Beneficial Use Pumping Instrumentation and Control Skid L

    SciTech Connect

    KOCH, M.R.

    1999-11-17

    This is a final Acceptance for Beneficial Use (ABU) for Pumping and Instrumentation Control (PIC) skid ''L''. PIC skid ''L'' is ready for pumping tank U-105. All the testing and documentation has been completed as required on the ABU checklist. This ABU covers only the readiness of the PIC skid ''L''. Other U-farm preparations including dilution tank fabrication, portable exhauster readiness, leak detection, valve pit preparation, and the Operation Control Station readiness are not part of this ABU. PIC skid ''L'' is a new skid fabricated and tested at Site Fabrication Services. The skid controls the jet pump and monitors various instruments associated with the pumping operation. This monitoring includes leak detection along the waste transfer route and flammable gases in the pump pit.

  11. Postoperative infant septicemia caused by Pseudomonas luteola (CDC group Ve-1) and Pseudomonas oryzihabitans (CDC group Ve-2).

    PubMed

    Freney, J; Hansen, W; Etienne, J; Vandenesch, F; Fleurette, J

    1988-06-01

    Pseudomonas luteola (CDC group Ve-1) and Pseudomonas oryzihabitans (CDC group Ve-2) were both isolated from the same blood culture of a 5-month-old infant, 8 days after open-heart surgery. He quickly responded to appropriate antibiotics. Carbon substrate assimilation tests and fatty acid analysis clearly differentiated these two rarely pathogenic organisms.

  12. Postoperative infant septicemia caused by Pseudomonas luteola (CDC group Ve-1) and Pseudomonas oryzihabitans (CDC group Ve-2).

    PubMed

    Freney, J; Hansen, W; Etienne, J; Vandenesch, F; Fleurette, J

    1988-06-01

    Pseudomonas luteola (CDC group Ve-1) and Pseudomonas oryzihabitans (CDC group Ve-2) were both isolated from the same blood culture of a 5-month-old infant, 8 days after open-heart surgery. He quickly responded to appropriate antibiotics. Carbon substrate assimilation tests and fatty acid analysis clearly differentiated these two rarely pathogenic organisms. PMID:3384937

  13. Postoperative infant septicemia caused by Pseudomonas luteola (CDC group Ve-1) and Pseudomonas oryzihabitans (CDC group Ve-2).

    PubMed Central

    Freney, J; Hansen, W; Etienne, J; Vandenesch, F; Fleurette, J

    1988-01-01

    Pseudomonas luteola (CDC group Ve-1) and Pseudomonas oryzihabitans (CDC group Ve-2) were both isolated from the same blood culture of a 5-month-old infant, 8 days after open-heart surgery. He quickly responded to appropriate antibiotics. Carbon substrate assimilation tests and fatty acid analysis clearly differentiated these two rarely pathogenic organisms. PMID:3384937

  14. Combustion characterization of beneficiated coal-based fuels

    SciTech Connect

    Chow, O.K.; Nsakala, N.Y.

    1990-11-01

    The Pittsburgh Energy Technology Center of the US Department of Energy has contracted with Combustion Engineering, Inc. (CE) to perform a three-year project on Combustion Characterization of Beneficiated Coal-Based Fuels.'' The beneficiated coals are produced by other contractors under the DOE Coal Preparation Program. Several contractor-developed advanced coal cleaning processes are being run at the cleaning facility in Homer City, Pennsylvania, to produce 20-ton batches of fuels for shipment to CE's laboratory in Windsor, Connecticut. CE then processes the products into either a coal-water fuel (CVVT) or a dry microfine pulverized coal (DMPC) form for combustion testing. The objectives of this project include: (1) the development of an engineering data base which will provide detailed information on the properties of BCFs influencing combustion, ash deposition, ash erosion, particulate collection, and emissions; and (2) the application of this technical data base to predict the performance and economic impacts of firing the BCFs in various commercial boiler designs. The technical approach used to develop the technical data includes: bench-scale fuel property, combustion, and ash deposition tests; pilot-scale combustion and ash effects tests; and full-scale combustion tests. Subcontractors to CE to perform parts of the test work are the Massachusetts Institute of Technology (MIT), Physical Science, Inc. Technology Company (PSIT) and the University of North Dakota Energy and Environmental Research Center (UNDEERC). Twenty fuels will be characterized during the three-year base program: three feed coals, fifteen BCFS, and two conventionally cleaned coals for full-scale tests. Approximately, nine BCFs will be in dry microfine coal (DMPC) form, and six BCFs will be in coal-water fuel (CWF) form. Additional BCFs would be characterized during optional project supplements.

  15. ASSESSING OF HERBIVOROUS AND BENEFICIAL INSECTS ON SWITCHGRASS IN UKRAINE.

    PubMed

    Stefanovska, T; Kucherovska, S; Pisdlisnyuk, V

    2014-01-01

    A perennial switchgrass, (Panicum virgatum L.), (C4) that is native to North America has good potential for biomass production because of its wide geographic distribution and adaptability to diverse environmental conditions. Insects can significantly impact the yield and quality of biofuel crops. If switchgrass are to be grown on marginally arable land or in monoculture, it are likely to be plagued with herbivore pests and plant diseases at a rate that exceeds what would be expected if the plants were not stressed in this manner. This biofuel crop has been under evaluation for commercial growing in Ukraine for eight years. However, insect diversity and the potential impact of pests on biomass production of this feedstock have not been accessed yet. The objective of our study, started in 2011, is a survey of switch grass insects by trophic groups and determine species that have pest status at two sites in the Central part of Ukraine (Kiev and Poltava regions). In Poltava site we investigated the effect of nine varieties of switchgrass (lowland and upland) to insects' diversity. We assessed changes over time in the densities of major insects' trophic groups, identifying potential pests and natural enemies. Obtained results indicates that different life stages of herbivorous insects from Hymenoptera, Homoptera, Diptera and Coleoptera orders were present on switchgrass during the growing season. Our study results suggests that choice of variety has an impact on trophic groups' structure and number of insects from different orders on swicthgrass. Herbivores and beneficial insects were the only groups that showed significant differences across sampling dates. The highest population of herbivores insects we recorded on 'Alamo' variety for studied years, although herbivore diversity tended to increase on 'Shelter', 'Alamo' and 'Cave-in-Rock' during 2012 and 2013. 'Dacotah', 'Nebraska', 'Sunburst', 'Forestburg' and 'Carthage' showed the highest level of beneficial insects

  16. Sweetgum: An ancient source of beneficial compounds with modern benefits

    PubMed Central

    Lingbeck, Jody M.; O’Bryan, Corliss A.; Martin, Elizabeth M.; Adams, Joshua P.; Crandall, Philip G.

    2015-01-01

    Sweetgum trees are large, deciduous trees found in Asia and North America. Sweetgum trees are important resources for medicinal and other beneficial compounds. Many of the medicinal properties of sweetgum are derived from the resinous sap that exudes when the outer bark of the tree has been damaged. The sap, known as storax, has been used for centuries to treat common ailments such as skin problems, coughs, and ulcers. More recently, storax has proven to be a strong antimicrobial agent even against multidrug resistant bacteria such as methicillin-resistant Staphylococcus aureus. In addition to the sap, the leaves, bark, and seeds of sweetgum also possess beneficial compounds such as shikimic acid, a precursor to the production of oseltamivir phosphate, the active ingredient in Tamiflu®–an antiviral drug effective against several influenza viruses. Other extracts derived from sweetgum trees have shown potential as antioxidants, anti-inflammatory agents, and chemopreventive agents. The compounds found in the extracts derived from sweetgum sap suppress hypertension in mice. Extracts from sweetgum seeds have anticonvulsant effects, which may make them suitable in the treatment of epilepsy. In addition to the potential medicinal uses of sweetgum extracts, the extracts of the sap possess antifungal activity against various phytopathogenic fungi and have been effective treatments for reducing nematodes and the yellow mosquito, Aedes aegypti, populations thus highlighting the potential of these extracts as environment-friendly pesticides and antifungal agents. The list of value-added products derived from sweetgum trees can be increased by continued research of this abundantly occurring tree. PMID:26009686

  17. Sweetgum: An ancient source of beneficial compounds with modern benefits.

    PubMed

    Lingbeck, Jody M; O'Bryan, Corliss A; Martin, Elizabeth M; Adams, Joshua P; Crandall, Philip G

    2015-01-01

    Sweetgum trees are large, deciduous trees found in Asia and North America. Sweetgum trees are important resources for medicinal and other beneficial compounds. Many of the medicinal properties of sweetgum are derived from the resinous sap that exudes when the outer bark of the tree has been damaged. The sap, known as storax, has been used for centuries to treat common ailments such as skin problems, coughs, and ulcers. More recently, storax has proven to be a strong antimicrobial agent even against multidrug resistant bacteria such as methicillin-resistant Staphylococcus aureus. In addition to the sap, the leaves, bark, and seeds of sweetgum also possess beneficial compounds such as shikimic acid, a precursor to the production of oseltamivir phosphate, the active ingredient in Tamiflu®-an antiviral drug effective against several influenza viruses. Other extracts derived from sweetgum trees have shown potential as antioxidants, anti-inflammatory agents, and chemopreventive agents. The compounds found in the extracts derived from sweetgum sap suppress hypertension in mice. Extracts from sweetgum seeds have anticonvulsant effects, which may make them suitable in the treatment of epilepsy. In addition to the potential medicinal uses of sweetgum extracts, the extracts of the sap possess antifungal activity against various phytopathogenic fungi and have been effective treatments for reducing nematodes and the yellow mosquito, Aedes aegypti, populations thus highlighting the potential of these extracts as environment-friendly pesticides and antifungal agents. The list of value-added products derived from sweetgum trees can be increased by continued research of this abundantly occurring tree.

  18. Heavy metal tolerance genes alter cellular thermodynamics in Pseudomonas putida and river Pseudomonas spp. and influence amebal predation.

    PubMed

    McTee, Michael R; Gibbons, Sean M; Feris, Kevin; Gordon, Nathan S; Gannon, James E; Ramsey, Philip W

    2013-10-01

    Predation rates were measured for two Acanthamoeba castellanii strains feeding on metal-tolerant and metal-sensitive strains of Pseudomonas putida and compared with cellular thermodynamic data. Predation rates by A. castellanii strain ATCC 30010 correlated with cell volume of the prey. To explore whether this observation could be environmentally relevant, pseudomonad species were isolated from a pristine and a metal-contaminated river and were paired based on phylogenetic and physiological relatedness. Then, cellular thermodynamics and predation rates were measured on the most similar pseudomonad pair. Under cadmium stress, the strain from contaminated river sediments, Pseudomonas sp. CF150, exited metabolic dormancy faster than its pair from pristine sediments, Pseudomonas sp. N9, but consumed available resources less efficiently (more energy was lost as heat). Predation rates by both strains of ameba were greater on Pseudomonas sp. CF150 than on Pseudomonas sp. N9 at the highest cadmium concentration. PMID:23895438

  19. Ethylene Glycol Metabolism by Pseudomonas putida

    PubMed Central

    Mückschel, Björn; Simon, Oliver; Klebensberger, Janosch; Graf, Nadja; Rosche, Bettina; Altenbuchner, Josef; Pfannstiel, Jens; Huber, Armin

    2012-01-01

    In this study, we investigated the metabolism of ethylene glycol in the Pseudomonas putida strains KT2440 and JM37 by employing growth and bioconversion experiments, directed mutagenesis, and proteome analysis. We found that strain JM37 grew rapidly with ethylene glycol as a sole source of carbon and energy, while strain KT2440 did not grow within 2 days of incubation under the same conditions. However, bioconversion experiments revealed metabolism of ethylene glycol by both strains, with the temporal accumulation of glycolic acid and glyoxylic acid for strain KT2440. This accumulation was further increased by targeted mutagenesis. The key enzymes and specific differences between the two strains were identified by comparative proteomics. In P. putida JM37, tartronate semialdehyde synthase (Gcl), malate synthase (GlcB), and isocitrate lyase (AceA) were found to be induced in the presence of ethylene glycol or glyoxylic acid. Under the same conditions, strain KT2440 showed induction of AceA only. Despite this difference, the two strains were found to use similar periplasmic dehydrogenases for the initial oxidation step of ethylene glycol, namely, the two redundant pyrroloquinoline quinone (PQQ)-dependent enzymes PedE and PedH. From these results we constructed a new pathway for the metabolism of ethylene glycol in P. putida. Furthermore, we conclude that Pseudomonas putida might serve as a useful platform from which to establish a whole-cell biocatalyst for the production of glyoxylic acid from ethylene glycol. PMID:23023748

  20. Methylmercury degradation by Pseudomonas putida V1.

    PubMed

    Cabral, Lucélia; Yu, Ri-Qing; Crane, Sharron; Giovanella, Patricia; Barkay, Tamar; Camargo, Flávio A O

    2016-08-01

    Environmental contamination of mercury (Hg) has caused public health concerns with focuses on the neurotoxic substance methylmercury, due to its bioaccumulation and biomagnification in food chains. The goals of the present study were to examine: (i) the transformation of methylmercury, thimerosal, phenylmercuric acetate and mercuric chloride by cultures of Pseudomonas putida V1, (ii) the presence of the genes merA and merB in P. putida V1, and (iii) the degradation pathways of methylmercury by P. putida V1. Strain V1 cultures readily degraded methylmercury, thimerosal, phenylmercury acetate, and reduced mercuric chloride into gaseous Hg(0). However, the Hg transformation in LB broth by P. putida V1 was influenced by the type of Hg compounds. The merA gene was detected in P. putida V1, on the other hand, the merB gene was not detected. The sequencing of this gene, showed high similarity (100%) to the mercuric reductase gene of other Pseudomonas spp. Furthermore, tests using radioactive (14)C-methylmercury indicated an uncommon release of (14)CO2 concomitant with the production of Hg(0). The results of the present work suggest that P. putida V1 has the potential to remove methylmercury from contaminated sites. More studies are warranted to determine the mechanism of removal of methylmercury by P. putida V1. PMID:27062344

  1. Ethylene glycol metabolism by Pseudomonas putida.

    PubMed

    Mückschel, Björn; Simon, Oliver; Klebensberger, Janosch; Graf, Nadja; Rosche, Bettina; Altenbuchner, Josef; Pfannstiel, Jens; Huber, Armin; Hauer, Bernhard

    2012-12-01

    In this study, we investigated the metabolism of ethylene glycol in the Pseudomonas putida strains KT2440 and JM37 by employing growth and bioconversion experiments, directed mutagenesis, and proteome analysis. We found that strain JM37 grew rapidly with ethylene glycol as a sole source of carbon and energy, while strain KT2440 did not grow within 2 days of incubation under the same conditions. However, bioconversion experiments revealed metabolism of ethylene glycol by both strains, with the temporal accumulation of glycolic acid and glyoxylic acid for strain KT2440. This accumulation was further increased by targeted mutagenesis. The key enzymes and specific differences between the two strains were identified by comparative proteomics. In P. putida JM37, tartronate semialdehyde synthase (Gcl), malate synthase (GlcB), and isocitrate lyase (AceA) were found to be induced in the presence of ethylene glycol or glyoxylic acid. Under the same conditions, strain KT2440 showed induction of AceA only. Despite this difference, the two strains were found to use similar periplasmic dehydrogenases for the initial oxidation step of ethylene glycol, namely, the two redundant pyrroloquinoline quinone (PQQ)-dependent enzymes PedE and PedH. From these results we constructed a new pathway for the metabolism of ethylene glycol in P. putida. Furthermore, we conclude that Pseudomonas putida might serve as a useful platform from which to establish a whole-cell biocatalyst for the production of glyoxylic acid from ethylene glycol.

  2. 17 CFR 229.403 - (Item 403) Security ownership of certain beneficial owners and management.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... of certain beneficial owners and management. 229.403 Section 229.403 Commodity and Securities... Management and Certain Security Holders § 229.403 (Item 403) Security ownership of certain beneficial owners and management. (a) Security ownership of certain beneficial owners. Furnish the following...

  3. Heterogeneity of heat-resistant proteases from milk Pseudomonas species.

    PubMed

    Marchand, Sophie; Vandriesche, Gonzalez; Coorevits, An; Coudijzer, Katleen; De Jonghe, Valerie; Dewettinck, Koen; De Vos, Paul; Devreese, Bart; Heyndrickx, Marc; De Block, Jan

    2009-07-31

    Pseudomonas fragi, Pseudomonas lundensis and members of the Pseudomonas fluorescens group may spoil Ultra High Temperature (UHT) treated milk and dairy products, due to the production of heat-stable proteases in the cold chain of raw milk. Since the aprX gene codes for a heat-resistant protease in P. fluorescens, the presence of this gene has also been investigated in other members of the genus. For this purpose an aprX-screening PCR test has been developed. Twenty-nine representatives of important milk Pseudomonas species and thirty-five reference strains were screened. In 42 out of 55 investigated Pseudomonas strains, the aprX gene was detected, which proves the potential of the aprX-PCR test as a screening tool for potentially proteolytic Pseudomonas strains in milk samples. An extensive study of the obtained aprX-sequences on the DNA and the amino acid level, however, revealed a large heterogeneity within the investigated milk isolates. Although this heterogeneity sets limitations to a general detection method for all proteolytic Pseudomonas strains in milk, it offers a great potential for the development of a multiplex PCR screening test targeting individual aprX-genes. Furthermore, our data illustrated the potential use of the aprX gene as a taxonomic marker, which may help in resolving the current taxonomic deadlock in the P. fluorescens group.

  4. Plant perceptions of plant growth-promoting Pseudomonas.

    PubMed Central

    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 pathogenic and plant growth-promoting Pseudomonas. They colonize the same ecological niches and possess similar mechanisms for plant colonization. Pathogenic, saprophytic and plant growth-promoting strains are often found within the same species, and the incidence and severity of Pseudomonas diseases are affected by environmental factors and host-specific interactions. Plants are faced with the challenge of how to recognize and exclude pathogens that pose a genuine threat, while tolerating more benign organisms. This review examines Pseudomonas from a plant perspective, focusing in particular on the question of how plants perceive and are affected by saprophytic and plant growth-promoting Pseudomonas (PGPP), in contrast to their interactions with plant pathogenic Pseudomonas. A better understanding of the molecular basis of plant-PGPP interactions and of the key differences between pathogens and PGPP will enable researchers to make more informed decisions in designing integrated disease-control strategies and in selecting, modifying and using PGPP for plant growth promotion, bioremediation and biocontrol. PMID:15306406

  5. Mild oxidative stress is beneficial for sperm telomere length maintenance

    PubMed Central

    Mishra, Swetasmita; Kumar, Rajeev; Malhotra, Neena; Singh, Neeta; Dada, Rima

    2016-01-01

    AIM: To evaluate telomere length in sperm DNA and its correlation with oxidative stress (normal, mild, severe). METHODS: The study included infertile men (n = 112) and age matched fertile controls (n = 102). The average telomere length from the sperm DNA was measured using a quantitative real time PCR based assay. Seminal reactive oxygen species (ROS) and 8-Isoprostane (8-IP) levels were measured by chemiluminescence assay and ELISA respectively. RESULTS: Average sperm telomere length in infertile men and controls was 0.609 ± 0.15 and 0.789 ± 0.060, respectively (P < 0.0001). Seminal ROS levels in infertile was higher [66.61 ± 28.32 relative light units (RLU)/s/million sperm] than in controls (14.04 ± 10.67 RLU/s/million sperm) (P < 0.0001). The 8-IP level in infertile men was significantly higher (421.55 ± 131.29 pg/mL) than in controls (275.94 ± 48.13 pg/mL) (P < 0.001). When correlated to oxidative stress, in normal range of oxidative stress (ROS, 0-21.3 RLU/s/million sperm) the average telomere length in cases was 0.663 ± 0.14, in mild oxidative stress (ROS, 21.3-35 RLU/s/million sperm) it was elevated (0.684 ± 0.12) and in severe oxidative stress (ROS > 35 RLU/s/million sperm) average telomere length was decreased to 0.595 ± 0.15. CONCLUSION: Mild oxidative stress results in lengthening of telomere length, but severe oxidative stress results in shorter telomeres. Although telomere maintenance is a complex trait, the study shows that mild oxidative stress is beneficial in telomere length maintenance and thus a delicate balance needs to be established to maximize the beneficial effects of free radicals and prevent harmful effects of supra physiological levels. Detailed molecular evaluation of telomere structure, its correlation with oxidative stress would aid in elucidating the cause of accelerated telomere length attrition. PMID:27376021

  6. Oxidation of substituted phenols by Pseudomonas putida F1 and Pseudomonas sp. strain JS6

    SciTech Connect

    Spain, J.C.; Gibson, D.T.

    1988-06-01

    The biodegradation of benzene, toluene, and chlorobenzenes by Pseudomonas putida involves the initial conversion of the parent molecules to cis-dihydrodiols by dioxygenase enzyme systems. The cis-dihydrodiols are then converted to the corresponding catechols by dihydrodiol dehydrogenase enzymes. Pseudomonas sp. strain JS6 uses a similar system for growth on toluene or dichlorobenzenes. We tested the wild-type organisms and a series of mutants for their ability to transform substituted phenols after induction with toluene. When grown on toluene, both wild-type organisms converted methyl-, chloro-, and nitro-substituted phenols to the corresponding catechols. Mutant strains deficient in dihydrodiol dehydrogenase or catechol oxygenase activities also transformed the phenols. Oxidation of phenols was closely correlated with the induction and activity of the toluene dioxygenase enzyme system.

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

    PubMed

    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.

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

    PubMed

    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. PMID:409295

  9. Beneficiation of flotation tailing from Polish copper sulfide ores

    SciTech Connect

    Luszczkiewicz, A.; Sztaba, K.S.

    1995-12-31

    Flotation tailing of Polish copper sulfide ores represents more than 90% of the mass of run-of-mine ore. The tailing contains mainly quartz, dolomite, clay minerals, traces of sulfides, and some accessory minerals. Almost all minerals of the tailing are well liberated and, therefore, any further beneficiation process applied to the tailing is expected to be inexpensive. In this work, results of investigations on utilization of flotation tailing using classification and gravity concentration are presented. It is shown that due to classification of flotation tailing in hydrocyclones, the coarse fraction becomes suitable material for gravity separation providing backfill material for underground mines as well as heavy minerals, a source of valuable rare elements. It was also found that heavy minerals separated by gravity methods contain a significant amount of rare elements such as zirconium, titanium, silver, rare earth metals, and uranium. The light fraction of the gravity separation contains well deslimed quartz particles and meets strict requirements for hydraulic filling material used for structural support in underground mines. Evaluation of the cost of the proposed technology indicated that investment to implement the method would provide a return within 2--4 years.

  10. Quantification of Efficiency of Beneficiation of Lunar Regolith

    NASA Technical Reports Server (NTRS)

    Trigwell, Steve; Lane, John; Captain, James; Weis, Kyle; Quinn, Jacqueline; Watanabe, Fumiya

    2011-01-01

    Electrostatic beneficiation of lunar regolith is being researched at Kennedy Space Center to enhance the ilmenite concentration of the regolith for the production of oxygen in in-situ resource utilization on the lunar surface. Ilmenite enrichment of up to 200% was achieved using lunar simulants. For the most accurate quantification of the regolith particles, standard petrographic methods are typically followed, but in order to optimize the process, many hundreds of samples were generated in this study that made the standard analysis methods time prohibitive. In the current studies, X-ray photoelectron spectroscopy (XPS) and Secondary Electron microscopy/Energy Dispersive Spectroscopy (SEM/EDS) were used that could automatically, and quickly, analyze many separated fractions of lunar simulant. In order to test the accuracy of the quantification, test mixture samples of known quantities of ilmenite (2, 5, 10, and 20 wt%) in silica (pure quartz powder), were analyzed by XPS and EDS. The results showed that quantification for low concentrations of ilmenite in silica could be accurately achieved by both XPS and EDS, knowing the limitations of the techniques. 1

  11. Nitride Nanoparticle Addition to Beneficially Reinforce Hybrid Magnesium Alloys

    NASA Astrophysics Data System (ADS)

    Paramsothy, Muralidharan; Chan, Jimmy; Kwok, Richard; Gupta, Manoj

    2013-02-01

    This study is aimed at understanding the function of two nitride nanoparticles regarding altering the mechanical properties of hybrid magnesium alloys in relation to nanoparticle-matrix reactivity. Nitride nanoparticles were selected for reinforcement purposes due to the affinity between magnesium and nitrogen (in parallel with the well-known magnesium-oxygen affinity). AZ91/ZK60A and AZ31/AZ91 hybrid magnesium alloys were reinforced with AlN and Si3N4 nanoparticles (respectively) using solidification processing followed by hot extrusion. Each nitride nanocomposite exhibited higher tensile strength than the corresponding monolithic hybrid alloy. However, AZ91/ZK60A/AlN exhibited slightly lower tensile ductility than AZ91/ZK60A, while AZ31/AZ91/Si3N4 exhibited higher tensile ductility than AZ31/AZ91. The formation of high strain zones (HSZs) (from particle surfaces inclusive) during tensile deformation as a significant mechanism supporting ductility enhancement was addressed. AZ91/ZK60A/AlN exhibited lower and higher compressive strength and ductility (respectively) compared to AZ91/ZK60A, while AZ31/AZ91/Si3N4 exhibited higher and unchanged compressive strength and ductility (respectively) compared to AZ31/AZ91. Nanograin formation (recrystallization) during room temperature compressive deformation (as a toughening mechanism) in relation to nanoparticle-stimulated nucleation (NSN) ability was also discussed. The beneficial (as well as comparative) effects of the respective nitride nanoparticle on each hybrid alloy are studied in this article.

  12. Pressurized fluidized-bed hydroretorting of Eastern oil shales -- Beneficiation

    SciTech Connect

    Roberts, M.J.; Lau, F.S.; Mensinger, M.C. ); Schultz, C.W.; Mehta, R.K.; Lamont, W.E. ); Chiang, S.H.; Venkatadri, R. ); Misra, M. )

    1992-05-01

    The Mineral Resources Institute at the University of Alabama, along with investigators from the University of Pittsburgh and the University of Nevada-Reno, have conducted a research program on the beneficiation, of Eastern oil shales. The objective of the research program was to evaluate and adapt those new and emerging technologies that have the potential to improve the economics of recovering oil from Eastern oil shales. The technologies evaluated in this program can be grouped into three areas: fine grinding kerogen/mineral matter separation, and waste treatment and disposal. Four subtasks were defined in the area of fine grinding. They were as follows: Ultrasonic Grinding, Pressure Cycle Comminution, Stirred Ball Mill Grinding, and Grinding Circuit Optimization. The planned Ultrasonic grinding research was terminated when the company that had contracted to do the research failed. Three technologies for effecting a separation of kerogen from its associated mineral matter were evaluated: column flotation, the air-sparged hydrocyclone, and the LICADO process. Column flotation proved to be the most effective means of making the kerogen/mineral matter separation. No problems are expected in the disposal of oil shale tailings. It is assumed that the tailings will be placed in a sealed pond and the water recycled to the plant as is the normal practice. It may be advantageous, however, to conduct further research on the recovery of metals as by-products and to assess the market for tailings as an ingredient in cement making.

  13. Rapamycin impairs HPD-induced beneficial effects on glucose homeostasis

    PubMed Central

    Chang, Geng-Ruei; Chiu, Yi-Shin; Wu, Ying-Ying; Lin, Yu-Chi; Hou, Po-Hsun; Mao, Frank Chiahung

    2015-01-01

    Background and Purpose Rapamycin, which is used clinically to treat graft rejection, has also been proposed to have an effect on metabolic syndrome; however, very little information is available on its effects in lean animals/humans. The purpose of this study was to characterize further the effects of the continuous use of rapamycin on glucose homeostasis in lean C57BL6/J mice. Experimental Approach Mice were fed a high-protein diet (HPD) for 12 weeks to develop a lean model and then were treated daily with rapamycin for 5 weeks while remaining on a HPD. Metabolic parameters, endocrine profiles, glucose tolerance tests, insulin sensitivity index, the expression of the glucose transporter GLUT4 and chromium distribution were measured in vivo. Key Results Lower body weight gain as well as a decreased caloric intake, fat pads, fatty liver scores, adipocyte size and glucose tolerance test values were observed in HPD-fed mice compared with mice fed a high-fat or standard diet. Despite these beneficial effects, rapamycin-treated lean mice showed greater glucose intolerance, reduced insulin sensitivity, lower muscle GLUT4 expression and changes in chromium levels in tissues even with high insulin levels. Conclusion and Implications Our findings demonstrate that continuous rapamycin administration may lead to the development of diabetes syndrome, as it was found to induce hyperglycaemia and glucose intolerance in a lean animal model. PMID:25884889

  14. Beneficial cilostazol therapeutic effects in mdx dystrophic skeletal muscle.

    PubMed

    Hermes, Túlio de Almeida; Macedo, Aline Barbosa; Fogaça, Aline Reis; Moraes, Luis Henrique Rapucci; de Faria, Felipe Meira; Kido, Larissa Akemi; Cagnon, Valéria Helena Alves; Minatel, Elaine

    2016-02-01

    This study evaluated the possible protective effects of cilostazol against myonecrosis in dystrophic diaphragm muscle in vivo, focusing on oxidative stress, the inflammatory response and angiogenesis. Young mdx mice, the experimental animal for Duchenne muscular dystrophy, received cilostazol for 14 days. A second group of mdx mice and a control group of C57BL/10 mice received a saline solution. In the mdx mice, cilostazol treatment was associated with reduced loss of muscle strength (-34.4%), decreased myonecrosis, reduced creatine kinase levels (-63.3%) and muscle fibres stained for immunoglobulin G in dystrophic diaphragm muscle (-81.1%), and a reduced inflammatory response, with a decreased inflammatory area (-22%), macrophage infiltration (-44.9%) and nuclear factor-κB (-24%) and tumour necrosis factor-α (-48%) content in dystrophic diaphragm muscle. Furthermore, cilostazol decreased oxidative stress and attenuated reactive oxygen species production (-74%) and lipid peroxidation (-17%) in dystrophic diaphragm muscle, and promoted the up-regulation of angiogenesis, increasing the number of microvessels (15%). In conclusion, the present results show that cilostazol has beneficial effects in dystrophic muscle. More research into the potential of cilostazol as a novel therapeutic agent for the treatment of dystrophinopathies is required.

  15. Beneficial role of bacterial endophytes in heavy metal phytoremediation.

    PubMed

    Ma, Ying; Rajkumar, Mani; Zhang, Chang; Freitas, Helena

    2016-06-01

    Phytoremediation is an emerging technology that uses plants and their associated microbes to clean up pollutants from the soil, water and air. In recent years, phytoremediation assisted by bacterial endophytes has been highly recommended for cleaning up of metal polluted soils since endophytic bacteria can alleviate metal toxicity in plant through their own metal resistance system and facilitate plant growth under metal stress. Endophytic bacteria improve plant growth in metal polluted soils in two different ways: 1) directly by producing plant growth beneficial substances including solubilization/transformation of mineral nutrients (phosphate, nitrogen and potassium), production of phytohormones, siderophores and specific enzymes; and 2) indirectly through controlling plant pathogens or by inducing a systemic resistance of plants against pathogens. Besides, they also alter metal accumulation capacity in plants by excreting metal immobilizing extracellular polymeric substances, as well as metal mobilizing organic acids and biosurfactants. The present work aims to review the progress of recent research on the isolation, identification and diversity of metal resistant endophytic bacteria and illustrate various mechanisms responsible for plant growth promotion and heavy metal detoxification/phytoaccumulation/translocation in plants.

  16. Beneficial effects of blueberries in experimental autoimmune encephalomyelitis.

    PubMed

    Xin, Junping; Feinstein, Douglas L; Hejna, Matthew J; Lorens, Stanley A; McGuire, Susan O

    2012-06-13

    Experimental autoimmune encephalomyelitis (EAE) is an animal model of autoimmune disease that presents with pathological and clinical features similar to those of multiple sclerosis (MS) including inflammation and neurodegeneration. This study investigated whether blueberries, which possess immunomodulatory, anti-inflammatory, and neuroprotective properties, could provide protection in EAE. Dietary supplementation with 1% whole, freeze-dried blueberries reduced disease incidence by >50% in a chronic EAE model (p < 0.01). When blueberry-fed mice with EAE were compared with control-fed mice with EAE, blueberry-fed mice had significantly lower motor disability scores (p = 0.03) as well as significantly greater myelin preservation in the lumbar spinal cord (p = 0.04). In a relapsing-remitting EAE model, blueberry-supplemented mice showed improved cumulative and final motor scores compared to control diet-fed mice (p = 0.01 and 0.03, respectively). These data demonstrate that blueberry supplementation is beneficial in multiple EAE models, suggesting that blueberries, which are easily administered orally and well-tolerated, may provide benefit to MS patients. PMID:22243431

  17. Beneficiation of U. S. oil shales by froth flotation

    SciTech Connect

    Krishnan, G.N.; Farley, E.P.; Murray, R.G.

    1983-04-01

    A bench-scale study of the beneficiation of western and eastern oil shales was conducted using ball mill grinding and froth flotation techniques. The liberation of organic and inorganic particles required reducing the particles to about 10-20 ..mu..m. Ball mill grinding energies were estimated to be about 50 kwh/ton for the western ''Anvil Points'' shale (13.5 wt% organics, 24 GPT) and 30 kwh/ton for the eastern ''Antrim'' shale (8 wt% organics, 7 GPT) for reduction to 20 ..mu..m. Froth flotation can increase the organic content of Anvil Points shale to about 27 wt% (50 GPT) at about 80% recovery. Froth flotation of finely ground Antrim shale produced concentrates containing 21 wt% organics (23 GPT) with 90% recovery. Higher grades of concentrates at lower recoveries can be obtained with additional stages of grinding and froth flotation. The separation efficiencies for the Anvil Points and Antrim shales were found to be 52% and 60% at the optimum conditions.

  18. Beneficial knockouts in Escherichia coli for producing hydrogen from glycerol.

    PubMed

    Tran, Kien Trung; Maeda, Toshinari; Sanchez-Torres, Viviana; Wood, Thomas K

    2015-03-01

    Glycerol is an inexpensive and abundant source for biofuel production on a large scale. Escherichia coli is a robust bacterium for producing hydrogen; however, its hydrogen productivity from glycerol is low. In this study, we conducted random transposon mutagenesis to identify uncharacterized genes whose inactivation is beneficial for hydrogen production from glycerol. Through screening, four mutant strains were found that are able to have from 1.3- to 1.6-fold higher hydrogen productivity (μmol H2/mg protein) than that of their parent strain (p < 0.05). These mutations were identified as aroM, gatZ, ycgR, and yfgI. The hydrogen yield (mol H2/mol glycerol consumed) of the aroM, gatZ, ycgR, and yfgI strains was 1.7-, 1.4-, 2.4-, and 2.1-fold higher than that of their parent strain, respectively. Moreover, a single disruption in these genes resulted in a faster cell growth and glycerol consumption under anaerobic conditions. In E. coli, AroM is predicted to be involved in the shikimate pathway, GatZ is tagatose-1,6-bisphosphate aldolase 2 which converts dihydroxyacetone phosphate to 1,6-biphosphate, and YcgR acts as a molecular brake limiting the swimming speed and ATP consumption. So far, the function of YfgI in general and in hydrogen production in particular remains unknown.

  19. Beneficial roles of dietary oleum cinnamomi in alleviating intestinal injury.

    PubMed

    Wang, Lei; Hou, Yongqing; Yi, Dan; Ding, Binying; Zhao, Di; Wang, Zhongxing; Zhu, Huiling; Liu, Yulan; Gong, Joshua; Assaad, Houssein; Wu, Guoyao

    2015-01-01

    Cinnamon is a traditional herb used for treatment of many human diseases. The most important chemical compounds of the essential oil are cinnamaldehyde and eugenol. Oleum cinnamomi (OCM, cinnamon oil) is increasingly used as a feed additive to animal diets. Beneficial effects of OCM in protecting tissues from inflammation and injury by endogenous and exogenous agents (such as hydrogen peroxide and lipopolysaccharide (LPS)) may result, in part, from its action on regulating amino acid metabolism in cells to favor the synthesis of glutathione (a major low-molecular-weight antioxidant) from cysteine, glycine and glutamate. In support of this notion, results of recent studies indicate that supplementing OCM (50 mg/kg diet) to a corn- and soybean meal-based diet for piglets weaned at 21 days of age enhances intestinal anti-oxidative capacity and reduces the incidence of diarrhea. Additionally, dietary supplementation with OCM ameliorates LPS-induced mucosal barrier dysfunction and mucosal damage in the small intestine. OCM holds great promise for protecting the gut from injury under conditions of inflammation, infections, and oxidative stress.

  20. Modified TMV Particles as Beneficial Scaffolds to Present Sensor Enzymes

    PubMed Central

    Koch, Claudia; Wabbel, Katrin; Eber, Fabian J.; Krolla-Sidenstein, Peter; Azucena, Carlos; Gliemann, Hartmut; Eiben, Sabine; Geiger, Fania; Wege, Christina

    2015-01-01

    Tobacco mosaic virus (TMV) is a robust nanotubular nucleoprotein scaffold increasingly employed for the high density presentation of functional molecules such as peptides, fluorescent dyes, and antibodies. We report on its use as advantageous carrier for sensor enzymes. A TMV mutant with a cysteine residue exposed on every coat protein (CP) subunit (TMVCys) enabled the coupling of bifunctional maleimide-polyethylene glycol (PEG)-biotin linkers (TMVCys/Bio). Its surface was equipped with two streptavidin [SA]-conjugated enzymes: glucose oxidase ([SA]-GOx) and horseradish peroxidase ([SA]-HRP). At least 50% of the CPs were decorated with a linker molecule, and all thereof with active enzymes. Upon use as adapter scaffolds in conventional “high-binding” microtiter plates, TMV sticks allowed the immobilization of up to 45-fold higher catalytic activities than control samples with the same input of enzymes. Moreover, they increased storage stability and reusability in relation to enzymes applied directly to microtiter plate wells. The functionalized TMV adsorbed to solid supports showed a homogeneous distribution of the conjugated enzymes and structural integrity of the nanorods upon transmission electron and atomic force microscopy. The high surface-increase and steric accessibility of the viral scaffolds in combination with the biochemical environment provided by the plant viral coat may explain the beneficial effects. TMV can, thus, serve as a favorable multivalent nanoscale platform for the ordered presentation of bioactive proteins. PMID:26734040

  1. Hydrophobic flocculation flotation for beneficiating fine coal and minerals

    SciTech Connect

    Song, S.; Valdivieso, A.L.

    1998-06-01

    It is shown that hydrophobic flocculation flotation (HFF) is an effective process to treat finely ground ores and slimes so as to concentrate coal and mineral values at a fine size range. The process is based on first dispersing the fine particles suspension, followed by flocculation of fine mineral values or coal in the form of hydrophobic surfaces either induced by specifically adsorbed surfactants or from nature at the conditioning of the slurry with the shear field of sufficient magnitude. The flocculation is intensified by the addition of a small amount of nonpolar oil. finely ground coals, ilmenite slimes, and gold finely disseminated in a slag have been treated by this process. Results are presented indicating that cleaned coal with low ash and sulfur remaining and high Btu recovery can be obtained, and the refractory ores of ilmenite slimes and fine gold-bearing slag can be reasonably concentrated, leading to better beneficiation results than other separation techniques. In addition, the main operating parameters affecting the HFF process are discussed.

  2. Primary beneficiation of tantalite using magnetic separation and acid leaching

    NASA Astrophysics Data System (ADS)

    Nete, M.; Koko, F.; Theron, T.; Purcell, W.; Nel, J. T.

    2014-12-01

    Primary beneficiation was successfully performed prior to dissolution of manganotantalite (sample A) and ferrotantalite (sample C) samples obtained from two different mines in the Naquissupa area, Mozambique. Magnetic separation removed the majority of iron and titanium, whereas H2SO4 leaching removed a large portion of thorium and uranium in these samples. Analytical results indicated that 64.14wt% and 72.04wt% of the total Fe and Ti, respectively, and ˜2wt% each of Nb2O5 and Ta2O5 were removed from sample C (ferrotantalite) using the magnetic separation method, whereas only 9.64wt% and 8.66wt% of total Fe2O3 and TiO2, respectively, and ˜2wt% each of Nb2O5 and Ta2O5 were removed from sample A (manganotantalite). A temperature of 50°C and a leaching time of 3 h in the presence of concentrated H2SO4 were observed to be the most appropriate leaching conditions for removal of radioactive elements from the tantalite ores. The results obtained for sample A under these conditions indicated that 64.14wt% U3O8 and 60.77wt% ThO2 were leached into the acidic solution, along with 4.45wt% and 0.99wt% of Nb2O5 and Ta2O5, respectively.

  3. Beneficial effects of footbaths in controlling spasticity after stroke

    NASA Astrophysics Data System (ADS)

    Matsumoto, Shuji; Shimodozono, Megumi; Etoh, Seiji; Shimozono, Yurika; Tanaka, Nobuyuki; Kawahira, Kazumi

    2010-07-01

    Footbaths are considered to provide beneficial thermal therapy for post-stroke patients with spasticity, but their anti-spastic effects have not been investigated comprehensively. The present study aimed to evaluate alterations in motor-neuron excitability using F-wave parameters in post-stroke patients with spastic hemiplegia. Subjects’ legs below the knee joint were immersed in water at 41°C and F-wave recordings were made over the abductor hallucis muscle before, immediately after, and 30 min after thermal treatment. Antidromic stimulation was performed on the tibial nerve at the ankle. Measurements included F-wave amplitude, F-wave/M-response ratio, changes in modified Ashworth scale (MAS), body temperature and surface-skin temperature. The mean values of both F-wave parameters were higher on the affected side before footbath treatment. In post-stroke patients, the mean values of F-wave parameters were significantly reduced after footbath treatment ( P < 0.01). The anti-spastic effects of footbath treatment were indicated by decreased F-wave parameters, in parallel with decreases in MAS. Body temperature was significantly increased both immediately after, and 30 min following footbath treatment in both groups, which appeared to play an important role in decreased spasticity. Surface-skin temperature increased immediately after footbath treatment in both groups and returned to baseline 30 min later. These findings demonstrate that the use of footbaths is an effective nonpharmacological anti-spastic treatment that might facilitate stroke rehabilitation.

  4. Graphic values for some organic constitutents of beneficiated coal samples

    SciTech Connect

    Kohlenberger, L.B. )

    1992-01-01

    Graphic techniques exist which can accurately predict values for calorific value, organic sulfur, and possibly other constituents of the organic portion of beneficiated coal sample fractions. These techniques also permit a determination of coal rank to be made without the use of the approximations required in the standard procedure. Fractions of IBC-101 with varying ash contents were produced by froth flotation. The various fractions were analyzed by the coal analysis laboratory and the particular data type was plotted in each case vs. the individual ash content of each fraction, using Lotus 123 and Freelace software packages. Such plots for calorific value and organic sulfur have, so far, been made. These curves and the information they contain are discussed in this report. A comparison of the graphic mineral matter value with the usual one calculated from the Parr approximation has been made. Eventually, the data may lead to an effective way to estimate inorganic carbon, hydrogen, nitrogen, and other organic constitents of coal. All data will be made available to researchers.

  5. Calcineurin determines toxic versus beneficial responses to α-synuclein

    PubMed Central

    Caraveo, Gabriela; Auluck, Pavan K.; Whitesell, Luke; Chung, Chee Yeun; Baru, Valeriya; Mosharov, Eugene V.; Yan, Xiaohui; Ben-Johny, Manu; Soste, Martin; Picotti, Paola; Kim, Hanna; Caldwell, Kim A.; Caldwell, Guy A.; Sulzer, David; Yue, David T.; Lindquist, Susan

    2014-01-01

    Calcineurin (CN) is a highly conserved Ca2+–calmodulin (CaM)-dependent phosphatase that senses Ca2+ concentrations and transduces that information into cellular responses. Ca2+ homeostasis is disrupted by α-synuclein (α-syn), a small lipid binding protein whose misfolding and accumulation is a pathological hallmark of several neurodegenerative diseases. We report that α-syn, from yeast to neurons, leads to sustained highly elevated levels of cytoplasmic Ca2+, thereby activating a CaM-CN cascade that engages substrates that result in toxicity. Surprisingly, complete inhibition of CN also results in toxicity. Limiting the availability of CaM shifts CN's spectrum of substrates toward protective pathways. Modulating CN or CN's substrates with highly selective genetic and pharmacological tools (FK506) does the same. FK506 crosses the blood brain barrier, is well tolerated in humans, and is active in neurons and glia. Thus, a tunable response to CN, which has been conserved for a billion years, can be targeted to rebalance the phosphatase’s activities from toxic toward beneficial substrates. These findings have immediate therapeutic implications for synucleinopathies. PMID:25122673

  6. Beneficiation of borax by reverse flotation in boron saturated brine.

    PubMed

    Cafer Cilek, Emin; Uresin, Hasan

    2005-10-15

    Flotation is one of the plausible methods for recovering borax fines discharged as fine waste to the tailings dam in the Kirka borax processing plant. A literature review dealing with the flotation behavior of boron minerals reveals that clay minerals in the boron ores coat boron minerals and thus deteriorate the quality of boron concentrates produced by direct flotation. The main objective of this study is therefore to recover borax fines from the tailings of the concentrator by reverse flotation. A three-level-factor experimental design was used to determine the main and interaction effects of variables selected on the metallurgical performance of reverse flotation. An analysis of variance for experimental results indicates that interaction effects of the variables for concentrate quality and recovery of B2O3 is nonsignificant and the most important variable for grade of concentrate and recovery is the collector dosage. It is shown that a concentrate assaying 11.25% B2O3 with 89.90% B2O3 recovery could be produced by means of single-stage (rougher) reverse flotation. Additionally, in order to produce a sufficient-quality concentrate, a multistage reverse flotation scheme involving rougher, scavenger, and two cleaners was devised. A final concentrate containing 23.47% B2O3 with 81.78% B2O3 recovery was obtained from these tests. The reverse flotation method can be thus considered as an important option for the beneficiation of borax fines.

  7. Beneficiation and hydroretorting of low grade oil shale

    SciTech Connect

    Tippin, R.B.; Hanna, J.; Janka, J.C.; Rex, R.C. Jr.

    1985-02-01

    A new approach to oil recovery from low grade oil shales has been developed jointly by the Mineral Resources Institute (MRI) of The University of Alabama and the HYCRUDE Corporation. The approach is based on the HYTORT process, which utilized hydrogen gas during the retorting process to enhance oil yields from many types of oil shales. The performance of the HYTORT process is further improved by combining it with MRI's froth flotation process. Taking advantage of differences in the surface properties of the kerogen and the inorganic mineral constituents of the oil shales, the MRI process can reject up to three quarters by weight of relatively kerogen-free inorganic fractions of the oil shale before HYTORT processing. The HYTORT and MRI processes are discussed. Results of tests by each process on oil shales of low to moderate inherent kerogen content are presented. Also discussed are the results of the combined processes on an Indiana New Albany oil shale. By combining the two processes, the raw shale which yielded 12 gallons of oil per ton by Fischer Assay was upgraded by flotation to a product yielding 27 gallons of Fischer Assay oil per ton. HYTORT processing of the beneficiated product recovered 54 gallons of oil per ton, an improvement in oil yield by a factor of 4.5 over the raw shale Fischer Assay.

  8. Clostridium butyricum: from beneficial to a new emerging pathogen.

    PubMed

    Cassir, N; Benamar, S; La Scola, B

    2016-01-01

    Clostridium butyricum, a strictly anaerobic spore-forming bacillus, is a common human and animal gut commensal bacterium, and is also frequently found in the environment. Whereas non-toxigenic strains are currently used as probiotics in Asia, other strains have been implicated in pathological conditions, such as botulism in infants or necrotizing enterocolitis in preterm neonates. In terms of the latter, within the same species, different strains have antagonist effects on the intestinal mucosa. In particular, short-chain fatty acids, which are products of carbohydrate fermentation, have a dose-dependent paradoxical effect. Moreover, toxin genes have been identified by genome sequencing in pathological strains. Asymptomatic carriage of these strains has also been reported. Herein, we provide an overview of the implications of C. butyricum for human health, from the beneficial to the pathogenic. We focus on pathogenic strains associated with the occurrence of necrotizing enterocolitis. We also discuss the need to use complementary microbiological methods, including culture, in order to better assess gut bacterial diversity and identify new emergent enteropathogens at the strain level. PMID:26493849

  9. Vesiculation from Pseudomonas aeruginosa under SOS

    PubMed Central

    Maredia, Reshma; Devineni, Navya; Lentz, Peter; Dallo, Shatha F.; Yu, JiehJuen; Guentzel, Neal; Chambers, James; Arulanandam, Bernard; Haskins, William E.; Weitao, Tao

    2012-01-01

    Bacterial infections can be aggravated by antibiotic treatment that induces SOS response and vesiculation. This leads to a hypothesis concerning association of SOS with vesiculation. To test it, we conducted multiple analyses of outer membrane vesicles (OMVs) produced from the Pseudomonas aeruginosa wild type in which SOS is induced by ciprofloxacin and from the LexA noncleavable (lexAN) strain in which SOS is repressed. The levels of OMV proteins, lipids, and cytotoxicity increased for both the treated strains, demonstrating vesiculation stimulation by the antibiotic treatment. However, the further increase was suppressed in the lexAN strains, suggesting the SOS involvement. Obviously, the stimulated vesiculation is attributed by both SOS-related and unrelated factors. OMV subproteomic analysis was performed to examine these factors, which reflected the OMV-mediated cytotoxicity and the physiology of the vesiculating cells under treatment and SOS. Thus, SOS plays a role in the vesiculation stimulation that contributes to cytotoxicity. PMID:22448133

  10. Pseudomonas aeruginosa endophthalmitis masquerading as chronic uveitis

    PubMed Central

    Nagaraj, Kalpana Badami; Jayadev, Chaitra

    2013-01-01

    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. PMID:23803484

  11. Regulation of pyrimidine formation in Pseudomonas oryzihabitans.

    PubMed

    West, Thomas P

    2007-10-01

    The regulation of pyrimidine formation in the opportunistic human pathogen Pseudomonas oryzihabitans was investigated at the level of enzyme synthesis and at the level of activity for the pyrimidine biosynthetic pathway enzyme aspartate transcarbamoylase. Although pyrimidine supplementation of succinate-grown P. oryzihabitans cells produced little effect on the de novo pyrimidine biosynthetic pathway enzyme activities, pyrimidine limitation experiments undertaken using an orotidine 5'-monophosphate decarboxylase mutant strain isolated from P. oryzihabitans ATCC 43272 indicated that repression of enzyme synthesis by pyrimidines was occurring. Following pyrimidine limitation of the succinate-grown decarboxylase mutant strain cells, aspartate transcarbamoylase and dihydroorotase activities were found to increase by about 3-fold while dihydroorotate dehydrogenase and orotate phosphoribosyltransferase activities were also observed to increase relative to their activities in the mutant strain cells grown on excess uracil. At the level of enzyme activity, aspartate transcarbamoylase in P. oryzihabitans was strongly inhibited by pyrophosphate, ADP, ATP and GTP in the presence of saturating substrate concentrations.

  12. The Accessory Genome of Pseudomonas aeruginosa

    PubMed Central

    Kung, Vanderlene L.; Ozer, Egon A.; Hauser, Alan R.

    2010-01-01

    Summary: Pseudomonas aeruginosa strains exhibit significant variability in pathogenicity and ecological flexibility. Such interstrain differences reflect the dynamic nature of the P. aeruginosa genome, which is composed of a relatively invariable “core genome” and a highly variable “accessory genome.” Here we review the major classes of genetic elements comprising the P. aeruginosa accessory genome and highlight emerging themes in the acquisition and functional importance of these elements. Although the precise phenotypes endowed by the majority of the P. aeruginosa accessory genome have yet to be determined, rapid progress is being made, and a clearer understanding of the role of the P. aeruginosa accessory genome in ecology and infection is emerging. PMID:21119020

  13. Glycopeptide dendrimers as Pseudomonas aeruginosa biofilm inhibitors.

    PubMed

    Reymond, Jean-Louis; Bergmann, Myriam; Darbre, Tamis

    2013-06-01

    Synthetic glycopeptide dendrimers composed of a branched oligopeptide tree structure appended with glycosidic groups at its multiple N-termini were investigated for binding to the Pseudomonas aeruginosa lectins LecB and LecA. These lectins are partly responsible for the formation of antibiotic resistant biofilms in the human pathogenic bacterium P. aeruginosa, which causes lethal airway infections in immune-compromised and cystic fibrosis patients. Glycopeptide dendrimers with high affinity to the lectins were identified by screening of combinatorial libraries. Several of these dendrimers, in particular the LecB specific glycopeptide dendrimers FD2 and D-FD2 and the LecA specific glycopeptide dendrimers GalAG2 and GalBG2, also efficiently block P. aeruginosa biofilm formation and induce biofilm dispersal in vitro. Structure-activity relationship and structural studies are reviewed, in particular the observation that multivalency is essential to the anti-biofilm effect in these dendrimers.

  14. Regulation of pyrimidine formation in Pseudomonas oryzihabitans.

    PubMed

    West, Thomas P

    2007-10-01

    The regulation of pyrimidine formation in the opportunistic human pathogen Pseudomonas oryzihabitans was investigated at the level of enzyme synthesis and at the level of activity for the pyrimidine biosynthetic pathway enzyme aspartate transcarbamoylase. Although pyrimidine supplementation of succinate-grown P. oryzihabitans cells produced little effect on the de novo pyrimidine biosynthetic pathway enzyme activities, pyrimidine limitation experiments undertaken using an orotidine 5'-monophosphate decarboxylase mutant strain isolated from P. oryzihabitans ATCC 43272 indicated that repression of enzyme synthesis by pyrimidines was occurring. Following pyrimidine limitation of the succinate-grown decarboxylase mutant strain cells, aspartate transcarbamoylase and dihydroorotase activities were found to increase by about 3-fold while dihydroorotate dehydrogenase and orotate phosphoribosyltransferase activities were also observed to increase relative to their activities in the mutant strain cells grown on excess uracil. At the level of enzyme activity, aspartate transcarbamoylase in P. oryzihabitans was strongly inhibited by pyrophosphate, ADP, ATP and GTP in the presence of saturating substrate concentrations. PMID:17910097

  15. Pseudomonas aeruginosa ventilator-associated pneumonia management

    PubMed Central

    Ramírez-Estrada, Sergio; Borgatta, Bárbara; Rello, Jordi

    2016-01-01

    Ventilator-associated pneumonia is the most common infection in intensive care unit patients associated with high morbidity rates and elevated economic costs; Pseudomonas aeruginosa is one of the most frequent bacteria linked with this entity, with a high attributable mortality despite adequate treatment that is increased in the presence of multiresistant strains, a situation that is becoming more common in intensive care units. In this manuscript, we review the current management of ventilator-associated pneumonia due to P. aeruginosa, the most recent antipseudomonal agents, and new adjunctive therapies that are shifting the way we treat these infections. We support early initiation of broad-spectrum antipseudomonal antibiotics in present, followed by culture-guided monotherapy de-escalation when susceptibilities are available. Future management should be directed at blocking virulence; the role of alternative strategies such as new antibiotics, nebulized treatments, and vaccines is promising. PMID:26855594

  16. Metabolism of 5-hydroxylysine in Pseudomonas fluorescens.

    PubMed Central

    Friede, J D; Henderson, L M

    1976-01-01

    Hydroxylysine is metabolized via two routes by a Pseudomonas fluorescens strain as shown by the oxidation of selected intermediates. Hydroxy-L-lysine is oxidized via a pathway analogous to the monooxygenase pathway for L-lysine, and data suggest that at least some of tthe enzymes are those involved in the metabolism of L-lysine. Hydroxy-L-lysine is also converted by a racemase to allohydroxy-D-lysine, which is then degraded via a pathway analogous to, but different from, that described for D-lysine, involving hydroxy-L-pipecolate, 2-amino-5-hydroxyadipate, and 2-hydroxyglutarate. Data obtained with mutants unable to oxidize L-pipecolate suggest that the enzymes for the metabolism of hydroxy-L-pipecolate are distinct from those for L-pipecolate. Studies on D- and L-lysine degradation have shown that the previously described pathways for these compounds are present in this soil pseudomonad. PMID:821924

  17. Maintenance of chromosome structure in Pseudomonas aeruginosa

    PubMed Central

    Rybenkov, Valentin V.

    2014-01-01

    Replication and segregation of genetic information is an activity central to the well-being of all living cells. Concerted mechanisms have evolved that ensure that each cellular chromosome is replicated once and only once per cell cycle and then faithfully segregated into daughter cells. Despite remarkable taxonomic diversity, these mechanisms are largely conserved across eubacteria, although species specific distinctions can often be noted. Here, we provide an overview of the current state of knowledge about maintenance of the chromosome structure in Pseudomonas aeruginosa. We focus on global chromosome organization and its dynamics during DNA replication and cell division. Special emphasis is made on contrasting these activities in P. aeruginosa and other bacteria. Among unique P. aeruginosa features are the presence of two distinct autonomously replicating sequences and multiple condensins, which suggests existence of novel regulatory mechanisms. PMID:24863732

  18. Pressurized fluidized-bed hydroretorting of Eastern oil shales -- Beneficiation. Topical report for Task 4, Beneficiation research

    SciTech Connect

    Roberts, M.J.; Lau, F.S.; Mensinger, M.C.; Schultz, C.W.; Mehta, R.K.; Lamont, W.E.; Chiang, S.H.; Venkatadri, R.; Misra, M.

    1992-05-01

    The Mineral Resources Institute at the University of Alabama, along with investigators from the University of Pittsburgh and the University of Nevada-Reno, have conducted a research program on the beneficiation, of Eastern oil shales. The objective of the research program was to evaluate and adapt those new and emerging technologies that have the potential to improve the economics of recovering oil from Eastern oil shales. The technologies evaluated in this program can be grouped into three areas: fine grinding kerogen/mineral matter separation, and waste treatment and disposal. Four subtasks were defined in the area of fine grinding. They were as follows: Ultrasonic Grinding, Pressure Cycle Comminution, Stirred Ball Mill Grinding, and Grinding Circuit Optimization. The planned Ultrasonic grinding research was terminated when the company that had contracted to do the research failed. Three technologies for effecting a separation of kerogen from its associated mineral matter were evaluated: column flotation, the air-sparged hydrocyclone, and the LICADO process. Column flotation proved to be the most effective means of making the kerogen/mineral matter separation. No problems are expected in the disposal of oil shale tailings. It is assumed that the tailings will be placed in a sealed pond and the water recycled to the plant as is the normal practice. It may be advantageous, however, to conduct further research on the recovery of metals as by-products and to assess the market for tailings as an ingredient in cement making.

  19. The beneficial effects of Brassica vegetables on human health.

    PubMed

    Kapusta-Duch, Joanna; Kopeć, Aneta; Piatkowska, Ewa; Borczak, Barbara; Leszczyńska, Teresa

    2012-01-01

    The products of plant origin are a rich source of biologically active substances, both nutritive and referred as anti-nutritive. A large group of these compounds are substances with antioxidant activity that fights against free radicals. In the family of Brassicaceae vegetables, Brassica, is the largest and most widely consumed a group of plants in Europe and all over the world. They are characterized by different levels of nutrients. However because of their large and frequent consumption, they may become a significant source of nutrients and bioactive compounds in the daily diet. The beneficial effects of Brassica vegetables on human health have been somewhat linked to phytochemicals. They prevent oxidative stress, induce detoxification enzymes, stimulate immune system, decrease the risk of cancers, inhibit malignant transformation and carcinogenic mutations, as well as, reduce proliferation of cancer cells. Brassica vegetables contain a lot of valuable metabolites, which are effective in chemoprevention of cancer, what has been already documented by numerous studies. Due to the presence of vitamins C and E, carotenoids and antioxidant enzymes such as catalase, superoxide dismutase (SOD) and peroxidase, these vegetables are considerable source ofantioxidants, and due to the presence of polyphenols and the sulfur-organic compounds exert also antimutagenic action. Moreover, these vegetables are also rich in glucosinolates, which are unstable compounds and undergo degradation into biologically active indoles and isothiocyanates under the influence of enzyme presented in plant tissues- myrosynase. These substances through the induction of enzymatic systems I and II phase of xenobiotics metabolism may affect the elimination or neutralization of carcinogenic and mutagenic factors, and consequently inhibit DNA methylation and cancer development. Despite many healthy benefits upon eating of cruciferous vegetables, it has been also seen a negative impact of their certain

  20. Small Beneficial Effect of Caffeinated Energy Drink Ingestion on Strength.

    PubMed

    Collier, Nora B; Hardy, Michelle A; Millard-Stafford, Mindy L; Warren, Gordon L

    2016-07-01

    Collier, NB, Hardy, MA, Millard-Stafford, ML, and Warren, GL. Small beneficial effect of caffeinated energy drink ingestion on strength. J Strength Cond Res 30(7): 1862-1870, 2016-Because caffeine ingestion has been found to increase muscle strength, our aim was to determine whether caffeine when combined with other potential ergogenic ingredients, such as those in commercial energy drinks, would have a similar effect. Fifteen young healthy subjects were used in a double-blind, repeated-measures experimental design. Each subject performed 3 trials, ingesting either a caffeinated energy drink, an uncaffeinated version of the drink, or a placebo drink. The interpolated twitch procedure was used to assess maximum voluntary isometric contraction (MVIC) strength, electrically evoked strength, and percent muscle activation during MVIC of the knee extensors both before and after drink ingestion, and after a fatiguing bout of contractions; electromyographic (EMG) amplitude of the knee extensors during MVIC was also assessed. The mean (±SE) change in MVIC strength from before to after drink ingestion was significantly greater for the caffeinated energy drink compared with placebo [+5.0 (±1.7) vs. -0.5 (±1.5)%] and the difference between the drinks remained after fatigue (p = 0.015); the strength changes for the uncaffeinated energy drink were not significantly different from those of the other 2 drinks at any time. There was no significant effect of drink type on the changes in electrically evoked strength, percent muscle activation, and EMG from before to after drink ingestion. This study indicates that a caffeinated energy drink can increase MVIC strength but the effect is modest and the strength increase cannot be attributed to increased muscle activation. Whether the efficacy of energy drinks can be attributed solely to caffeine remains unclear.

  1. Toxicity of fruit fly baits to beneficial insects in citrus.

    PubMed Central

    Michaud, J.P.

    2003-01-01

    Two fruit fly baits, Nu-Lure®/malathion and GF-120 (Spinosad®) were evaluated in the laboratory for non-target impacts on beneficial insects. Nu-Lure/malathion proved attractive and toxic to adults and larvae of the coccinellid species, Curinus coeruleus Mulsant, Cycloneda sanguinea L. and Harmonia axyridis Pallas, a lacewing species, Chrysoperla rufilabris Burmeister. The coccinellids Olla v-nigrum Mulsant, Scymnus sp. and nymphs of the insidious flower bug, Orius insidiosus (Say) did not succumb to Nu-Lure baits, even in no-choice situations. Nu-Lure was also attractive and lethal to adults of two aphidophagous flies; Leucopis sp. and the syrphid fly Pseudodorus clavatus (F.). Both Nu-Lure and GF-120 caused significant mortality to the parasitoid wasps, Aphytis melinus De Bach and Lysiphlebus testaceipes Cresson, within 24 h of exposure. However, GF-120 caused no significant mortality to any coccinellid in either choice or no-choice situations, despite considerable consumption of baits. Adults of P. clavatus tended to avoid GF-120, although mortality was significant in no-choice tests. Although larvae and adults of the lacewing C. rufilabris consumed GF-120, mortality was delayed; adults died 48 -96 h post-exposure and those exposed as larvae died two weeks later in the pupal stage. The Nu-Lure bait did not appear palatable to any of the insects, but the high concentration of malathion (195,000 ppm) caused rapid mortality to susceptible insects. Nu-Lure bait without malathion also caused significant mortality to flies and lacewings in cage trials. Although GF-120 bait appeared more benign overall, further research efforts are warranted to increase its selectivity for target fly species and reduce its attractiveness to parasitoids and lacewings. I conclude that the Florida “fly free zone” protocol in its current form is not compatible with an IPM approach to commercial citrus production. PMID:15841224

  2. Beneficial effects of Bacopa monnieri extract on opioid induced toxicity.

    PubMed

    Shahid, Muhammad; Subhan, Fazal; Ullah, Ihsan; Ali, Gowhar; Alam, Javaid; Shah, Rehmat

    2016-02-01

    The present study examined the hepatotoxicity and nephrotoxicity of morphine and illicit street heroin and their amelioration by a standardized methanolic extract of Bacopa monnieri (L.) (mBME) in rats. Morphine or street heroin was administered at a dose of 20 mg/kg for 14 and 21 days. mBME (40 mg/kg) or ascorbic acid (50 mg/kg) was administered two hours before morphine or street heroin. High performance liquid chromatography (HPLC) was used for the standardization of bacoside-A major components in mBME. The antioxidant potential of mBME was evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging assay. Administration of morphine and street heroin resulted in marked elevation of serum alanine aminotransferase (ALT), aspartate aminotransferase (AST) and creatinine. Histopathological changes induced by morphine and street heroin after 14 days were of reversible nature while treatment for 21 days was associated with irreversible changes. Pretreatment with mBME or ascorbic acid restored the elevation of serum ALT, AST and creatinine and protected liver and kidneys from the toxicological influence of morphine and street heroin. HPLC analysis showed that mBME contained bacoside-A major components i.e. bacoside-A3 (37.5 μg/mg), bacopaside-II (4.62 μg/mg) and bacopasaponin-C (1.91 μg/mg). The EC50 for the DPPH free radical scavenging assay revealed that mBME possessed strong antioxidant potential. These results concluded that as compared to morphine, street heroin was associated with severe biochemical and histopathological changes in the liver and kidneys. Bacopa monnieri having strong antioxidant potential may provide a beneficial herbal remedy for the efficient management of opioid related hepatotoxicity and nephrotoxicity. PMID:27441247

  3. Beneficial effects of Bacopa monnieri extract on opioid induced toxicity.

    PubMed

    Shahid, Muhammad; Subhan, Fazal; Ullah, Ihsan; Ali, Gowhar; Alam, Javaid; Shah, Rehmat

    2016-02-01

    The present study examined the hepatotoxicity and nephrotoxicity of morphine and illicit street heroin and their amelioration by a standardized methanolic extract of Bacopa monnieri (L.) (mBME) in rats. Morphine or street heroin was administered at a dose of 20 mg/kg for 14 and 21 days. mBME (40 mg/kg) or ascorbic acid (50 mg/kg) was administered two hours before morphine or street heroin. High performance liquid chromatography (HPLC) was used for the standardization of bacoside-A major components in mBME. The antioxidant potential of mBME was evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging assay. Administration of morphine and street heroin resulted in marked elevation of serum alanine aminotransferase (ALT), aspartate aminotransferase (AST) and creatinine. Histopathological changes induced by morphine and street heroin after 14 days were of reversible nature while treatment for 21 days was associated with irreversible changes. Pretreatment with mBME or ascorbic acid restored the elevation of serum ALT, AST and creatinine and protected liver and kidneys from the toxicological influence of morphine and street heroin. HPLC analysis showed that mBME contained bacoside-A major components i.e. bacoside-A3 (37.5 μg/mg), bacopaside-II (4.62 μg/mg) and bacopasaponin-C (1.91 μg/mg). The EC50 for the DPPH free radical scavenging assay revealed that mBME possessed strong antioxidant potential. These results concluded that as compared to morphine, street heroin was associated with severe biochemical and histopathological changes in the liver and kidneys. Bacopa monnieri having strong antioxidant potential may provide a beneficial herbal remedy for the efficient management of opioid related hepatotoxicity and nephrotoxicity.

  4. The Beneficial Role of Retinoids in Glomerular Disease

    PubMed Central

    Mallipattu, Sandeep K.; He, John Cijiang

    2015-01-01

    The primary etiology of CKD is a direct consequence of initial dysfunction and injury of the glomerulus, the main filtration system. Podocytes are terminally differentiated epithelial cells in the glomerulus, whose major function is the maintenance of this renal filtration barrier. Podocyte injury is implicated in many glomerular diseases including focal segmental glomerular sclerosis and HIV-associated nephropathy. In many of these diseased conditions, the podocyte can either undergo dedifferentiation and proliferation, apoptosis, or cell detachment. Regardless of the initial type of injury, the podocyte ultimately loses its functional capacity to maintain the glomerular filtration barrier. Significant injury resulting in a loss of the podocytes and failure to maintain the renal filtration barrier contributes to progressive kidney disease. Consequently, therapies that prevent podocyte injury and promote their regeneration will have a major clinical impact on glomerular disease. Retinoic acid (RA), which is a derivative of vitamin A, has many cellular functions including induction of cell differentiation, regulation of apoptosis, and inhibition of inflammation and proliferation. RA is required for kidney development and is essential for cellular differentiation in the setting of podocyte injury. The mechanism by which RA directs its beneficial effects is multifactorial, ranging from its anti-inflammatory and anti-fibrotic effects to a direct effect of upregulating podocyte differentiation markers in the podocyte. The focus of this review is to provide an overview of RA in kidney development and glomerular disease. We also highlight the key mechanism(s) by which RA restores podocyte differentiation markers and ameliorates glomerular disease. PMID:25853135

  5. Small Beneficial Effect of Caffeinated Energy Drink Ingestion on Strength.

    PubMed

    Collier, Nora B; Hardy, Michelle A; Millard-Stafford, Mindy L; Warren, Gordon L

    2016-07-01

    Collier, NB, Hardy, MA, Millard-Stafford, ML, and Warren, GL. Small beneficial effect of caffeinated energy drink ingestion on strength. J Strength Cond Res 30(7): 1862-1870, 2016-Because caffeine ingestion has been found to increase muscle strength, our aim was to determine whether caffeine when combined with other potential ergogenic ingredients, such as those in commercial energy drinks, would have a similar effect. Fifteen young healthy subjects were used in a double-blind, repeated-measures experimental design. Each subject performed 3 trials, ingesting either a caffeinated energy drink, an uncaffeinated version of the drink, or a placebo drink. The interpolated twitch procedure was used to assess maximum voluntary isometric contraction (MVIC) strength, electrically evoked strength, and percent muscle activation during MVIC of the knee extensors both before and after drink ingestion, and after a fatiguing bout of contractions; electromyographic (EMG) amplitude of the knee extensors during MVIC was also assessed. The mean (±SE) change in MVIC strength from before to after drink ingestion was significantly greater for the caffeinated energy drink compared with placebo [+5.0 (±1.7) vs. -0.5 (±1.5)%] and the difference between the drinks remained after fatigue (p = 0.015); the strength changes for the uncaffeinated energy drink were not significantly different from those of the other 2 drinks at any time. There was no significant effect of drink type on the changes in electrically evoked strength, percent muscle activation, and EMG from before to after drink ingestion. This study indicates that a caffeinated energy drink can increase MVIC strength but the effect is modest and the strength increase cannot be attributed to increased muscle activation. Whether the efficacy of energy drinks can be attributed solely to caffeine remains unclear. PMID:26670991

  6. A Fatal Case of "Bullous Erysipelas-like" Pseudomonas Vasculitis.

    PubMed

    Yang, Sam Shiyao; Chandran, Nisha Suyien; Huang, Jing Xiang; Tan, Kong-Bing; Aw, Derrick Chen-Wee

    2016-01-01

    Erysipelas is a generally benign superficial bacterial skin infection, and its bullous form constitutes a rare and more severe variant. We describe the first and fatal case of "bullous erysipelas-like" septic vasculitis due to Pseudomonas bacteremi. A 69-year-old Chinese man presenting with diarrhea and septic shock initially began to rapidly develop sharply defined erythematous plaques with non-hemorrhagic bullae over his lower limbs. Culture of the aspirate from the bullae was positive for Pseudomonas aeruginosa. This was also consistent with his blood cultures showing Pseudomonas bacteremia. Histology of the skin lesion showed microthrombi and neutrophilic infiltrates in blood vessels with Gram-negative bacilli extruding from the vessel walls, characteristic of septic vasculitis. The bullous erysipelas-like lesions seen in this patient represents a rare manifestation of both septic vasculitis and Pseudomonas infection. PMID:26955132

  7. Genetic construction of recombinant Pseudomonas chlororaphis for improved glycerol utilization

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this study is to improve by genetic engineering the glycerol metabolic capability of Pseudomonas chlororaphis which is capable of producing commercially valuable biodegradable poly(hydroxyalkanoate) (PHA) and biosurfactant rhamnolipids (RLs). In the study, glycerol uptake facilitat...

  8. Pseudomonas aeruginosa Dose-Response and Bathing Water Infection

    EPA Science Inventory

    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 ...

  9. New strategies for genetic engineering Pseudomonas syringae using recombination

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  10. A Fatal Case of "Bullous Erysipelas-like" Pseudomonas Vasculitis.

    PubMed

    Yang, Sam Shiyao; Chandran, Nisha Suyien; Huang, Jing Xiang; Tan, Kong-Bing; Aw, Derrick Chen-Wee

    2016-01-01

    Erysipelas is a generally benign superficial bacterial skin infection, and its bullous form constitutes a rare and more severe variant. We describe the first and fatal case of "bullous erysipelas-like" septic vasculitis due to Pseudomonas bacteremi. A 69-year-old Chinese man presenting with diarrhea and septic shock initially began to rapidly develop sharply defined erythematous plaques with non-hemorrhagic bullae over his lower limbs. Culture of the aspirate from the bullae was positive for Pseudomonas aeruginosa. This was also consistent with his blood cultures showing Pseudomonas bacteremia. Histology of the skin lesion showed microthrombi and neutrophilic infiltrates in blood vessels with Gram-negative bacilli extruding from the vessel walls, characteristic of septic vasculitis. The bullous erysipelas-like lesions seen in this patient represents a rare manifestation of both septic vasculitis and Pseudomonas infection.

  11. Isolation of oxidase-negative Pseudomonas aeruginosa from sputum culture.

    PubMed Central

    Hampton, K D; Wasilauskas, B L

    1979-01-01

    Two isolates of Pseudomonas aeruginosa lacking characteristic indophenol oxidase were recovered from a sputum specimen. A discussion of the characteristic biochemical tests and antibiograms along with a possible explanation for this phenomenon is presented. PMID:225349

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

    ERIC Educational Resources Information Center

    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)

  13. Transcript and metabolite analysis of the Trichoderma-induced systemic resistance response to Pseudomonas syringae in Arabidopsis thaliana.

    PubMed

    Brotman, Yariv; Lisec, Jan; Méret, Michaël; Chet, Ilan; Willmitzer, Lothar; Viterbo, Ada

    2012-01-01

    In the present study we have assessed, by transcriptional and metabolic profiling, the systemic defence response of Arabidopsis thaliana plants to the leaf pathogen Pseudomonas syringae pv. tomato DC3000 (Pst) induced by the beneficial fungus Trichoderma asperelloides T203. Expression analysis (qPCR) of a set of 137 Arabidopsis genes related to Pst defence responses showed that T203 root colonization is not associated with major detectable transcriptomic changes in leaves. However, plants challenged with the bacterial pathogen showed quantitative differences in gene expression when pre-inoculated with T203, supporting priming of the plant by this beneficial fungus. Among the defence-related genes affected by T203, lipid transfer protein (LTP)4, which encodes a member of the lipid transfer pathogenesis-related family, is upregulated, whereas the WRKY40 transcription factor, known to contribute to Arabidopsis susceptibility to bacterial infection, shows reduced expression. On the other hand, root colonization by this beneficial fungus substantially alters the plant metabolic profile, including significant changes in amino acids, polyamines, sugars and citric acid cycle intermediates. This may in part reflect an increased energy supply required for the activation of plant defences and growth promotion effects mediated by Trichoderma species.

  14. [Phylogenetic analysis of lupine's bacterial wet rot--"Pseudomonas xanthochlora"].

    PubMed

    Dankevitch, L A

    2011-01-01

    The sequencing of 16S rRNA gene nucleotide chain of the 12 "P. xanthochlora" strains, collection Pseudomonas marginalis 8572 strain and Pseudomonas marginalis pv. marginalis 9175T P. fluorescens B-17T typical strains has been determined. The analysis of the 16S rRNA gene nucleotide chain showed high level of homology (98-99%) of "P. xanthochlora" investigated strains with the same of representatives of both P. fluorescens and P. marginalis species.

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

    PubMed

    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.

  16. Expression and localization of an ice nucleating protein from a soil bacterium, Pseudomonas borealis.

    PubMed

    Vanderveer, Tara L; Choi, Julie; Miao, Denian; Walker, Virginia K

    2014-08-01

    An ice nucleating protein (INP) coding region with 66% sequence identity to the INP of Pseudomonas syringae was previously cloned from P. borealis, a plant beneficial soil bacterium. Ice nucleating activity (INA) in the P. borealis DL7 strain was highest after transfer of cultures to temperatures just above freezing. The corresponding INP coding sequence (inaPb or ina) was used to construct recombinant plasmids, with recombinant expression visualized using a green fluorescent protein marker (gfp encoding GFP). Although the P. borealis strain was originally isolated by ice-affinity, bacterial cultures with membrane-associated INP-GFP did not adsorb to pre-formed ice. Employment of a shuttle vector allowed expression of ina-gfp in both Escherichia coli and Pseudomonas cells. At 27 °C, diffuse fluorescence appeared throughout the cells and was associated with low INA. However, after transfer of cultures to 4 °C, the protein localized to the poles coincident with high INA. Transformants with truncated INP sequences ligated to either gfp, or an antifreeze protein-gfp fusion showed that the repetitive ice-nucleation domain was not necessary for localization. Such localization is consistent with the flanking residues of the INP associating with a temperature-dependent secretion apparatus. A polar location would facilitate INP-INP interactions resulting in the formation of larger aggregates, serving to increase INA. Expression of INPs by P. borealis could function as an efficient atmospheric dispersal mechanism for these soil bacteria, which are less likely to use these proteins for nutrient procurement, as has been suggested for P. syringae. PMID:24930584

  17. Draft Genome Sequences of the Antimicrobial Producers Pseudomonas sp. TAA207 and Pseudomonas sp. TAD18 Isolated from Antarctic Sediments

    PubMed Central

    Presta, Luana; Inzucchi, Ilaria; Bosi, Emanuele; Fondi, Marco; Perrin, Elena; Maida, Isabel; Miceli, Elisangela; Tutino, Maria Luisa; Lo Giudice, Angelina; de Pascale, Donatella

    2016-01-01

    We report here the draft genome sequence of the Pseudomonas sp. TAA207 and Pseudomonas sp. TAD18 strains, isolated from Antarctic sediments during a summer campaign near coastal areas of Terra Nova Bay (Antarctica). Genome sequence knowledge allowed the identification of genes associated with the production of bioactive compounds and antibiotic resistance. Furthermore, it will be instrumental for comparative genomics and the fulfillment of both basic and application-oriented investigations. PMID:27469957

  18. Draft Genome Sequences of the Antimicrobial Producers Pseudomonas sp. TAA207 and Pseudomonas sp. TAD18 Isolated from Antarctic Sediments.

    PubMed

    Presta, Luana; Inzucchi, Ilaria; Bosi, Emanuele; Fondi, Marco; Perrin, Elena; Maida, Isabel; Miceli, Elisangela; Tutino, Maria Luisa; Lo Giudice, Angelina; de Pascale, Donatella; Fani, Renato

    2016-01-01

    We report here the draft genome sequence of the Pseudomonas sp. TAA207 and Pseudomonas sp. TAD18 strains, isolated from Antarctic sediments during a summer campaign near coastal areas of Terra Nova Bay (Antarctica). Genome sequence knowledge allowed the identification of genes associated with the production of bioactive compounds and antibiotic resistance. Furthermore, it will be instrumental for comparative genomics and the fulfillment of both basic and application-oriented investigations. PMID:27469957

  19. Pseudomonas putida and Pseudomonas fluorescens Species Group Recovery from Human Homes Varies Seasonally and by Environment.

    PubMed

    Remold, Susanna K; Purdy-Gibson, Megan E; France, Michael T; Hundley, Thomas C

    2015-01-01

    By shedding light on variation in time as well as in space, long-term biogeographic studies can help us define organisms' distribution patterns and understand their underlying drivers. Here we examine distributions of Pseudomonas in and around 15 human homes, focusing on the P. putida and P. fluorescens species groups. We describe recovery from 10,941 samples collected during up to 8 visits per home, occurring on average 2.6 times per year. We collected a mean of 141 samples per visit, from sites in most rooms of the house, from the surrounding yards, and from human and pet occupants. We recovered Pseudomonas in 9.7% of samples, with the majority of isolates being from the P. putida and P. fluorescens species groups (approximately 62% and 23% of Pseudomonas samples recovered respectively). Although representatives of both groups were recovered from every season, every house, and every type of environment sampled, recovery was highly variable across houses and samplings. Whereas recovery of P. putida group was higher in summer and fall than in winter and spring, P. fluorescens group isolates were most often recovered in spring. P. putida group recovery from soils was substantially higher than its recovery from all other environment types, while higher P. fluorescens group recovery from soils than from other sites was much less pronounced. Both species groups were recovered from skin and upper respiratory tract samples from healthy humans and pets, although this occurred infrequently. This study indicates that even species that are able to survive under a broad range of conditions can be rare and variable in their distributions in space and in time. For such groups, determining patterns and causes of stochastic and seasonal variability may be more important for understanding the processes driving their biogeography than the identity of the types of environments in which they can be found.

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

    PubMed

    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.

  1. Effectiveness of beneficial plant-microbe interactions under hypobaric and hypoxic conditions in an advanced life support system

    NASA Astrophysics Data System (ADS)

    MacIntyre, Olathe; Stasiak, Michael; Cottenie, Karl; Trevors, Jack; Dixon, Mike

    An assembled microbial community in the hydroponics solution of an advanced life support system may improve plant performance and productivity in three ways: (1) exclusion of plant pathogens from the initial community, (2) resistance to infection, and (3) plant-growth promotion. However, the plant production area is likely to have a hypobaric (low pressure) and hypoxic (low oxygen) atmosphere to reduce structural mass and atmosphere leakage, and these conditions may alter plant-microbe interactions. Plant performance and productivity of radish (Raphanus sativus L. cv. Cherry Bomb II) grown under hypobaric and hypoxic conditions were investigated at the University of Guelph's Controlled Environment Systems Research Facility. Changes in the microbial communities that routinely colonized the re-circulated nutrient solution, roots, and leaves of radishes in these experiments were quantified in terms of similarity in community composition, abundance of bacteria, and community diversity before and after exposure to hypobaric and hypoxic conditions relative to communities maintained at ambient growth conditions. The microbial succession was affected by extreme hypoxia (2 kPa oxygen partial pressure) while hypobaria as low as 10 kPa total pressure had little effect on microbial ecology. There were no correlations found between the physiological profile of these unintentional microbial communities and radish growth. The effects of hypobaric and hypoxic conditions on specific plant-microbe interactions need to be determined before beneficial gnotobiotic communities can be developed for use in space. The bacterial strains Tal 629 of Bradyrhizobium japonicum and WCS417 of Pseudomonas fluorescens, and the plant pathogen Fusarium oxysporum f. sp. raphani will be used in future experiments. B. japonicum Tal 629 promotes radish growth in hydroponics systems and P. fluorescens WCS417 induces systemic resistance to fusarium wilt (F. oxysporum f. sp. raphani) in radish under ambient

  2. Comparative in vitro activities of newer quinolones against Pseudomonas species and Xanthomonas maltophilia isolated from patients with cancer.

    PubMed Central

    Rolston, K V; Messer, M; Ho, D H

    1990-01-01

    The in vitro susceptibilities of three Pseudomonas species (Pseudomonas aeruginosa, Pseudomonas putida, and Pseudomonas fluorescens) and Xanthomonas maltophilia to quinolone antimicrobial agents were determined. Several newer agents, particularly PD117558, PD117596, PD127391, sparfloxacin (AT-4140), A-56620, and temafloxacin, were active against Pseudomonas species. X. maltophilia isolates were generally less susceptible than were Pseudomonas isolates but were inhibited by some of the newer quinolones. PMID:2285297

  3. Ribotype analysis of Pseudomonas pseudomallei isolates.

    PubMed Central

    Sexton, M M; Goebel, L A; Godfrey, A J; Choawagul, W; White, N J; Woods, D E

    1993-01-01

    No epidemiological typing system to differentiate among Pseudomonas pseudomallei isolates has been available. Ribotype analysis was developed and used to examine 74 clinical and 10 environmental isolates of P. pseudomallei from Thailand. Six P. pseudomallei ribotypes were identified from restriction fragment polymorphisms of EcoRI chromosomal digests. The predominant ribotype, A, was found in 59 of the isolates examined. By using patterns from hybridizations with SalI, HindIII, and PstI restriction digests, isolates of ribotype A were subdivided into a further five subtypes, giving a total of 10 differentiable P. pseudomallei types. In 23 of 34 melioidosis patients studied, multiple P. pseudomallei isolates were present. In all but one of these patients, a single ribotype of the organism was present. Isolation of two different ribotypes of P. pseudomallei from one patient, one each in sputum and urine, suggests that superinfection may have occurred. The ribotype was shown to be conserved during the course of antibiotic treatments in seven patients studied, although the antibiotic sensitivity patterns in the isolates from these patients varied. The prevalence of subtype A1 in clinical and environmental specimens suggests that this strain may be predominant in this geographical location. These results demonstrate the usefulness of the ribotyping method for epidemiological studies of P. pseudomallei. Images PMID:7679401

  4. Developing an international Pseudomonas aeruginosa reference panel

    PubMed Central

    De Soyza, Anthony; Hall, Amanda J; Mahenthiralingam, Eshwar; Drevinek, Pavel; Kaca, Wieslaw; Drulis-Kawa, Zuzanna; Stoitsova, Stoyanka R; Toth, Veronika; Coenye, Tom; Zlosnik, James E A; Burns, Jane L; Sá-Correia, Isabel; De Vos, Daniel; Pirnay, Jean-Paul; Kidd, Timothy J; Reid, David; Manos, Jim; Klockgether, Jens; Wiehlmann, Lutz; Tümmler, Burkhard; McClean, Siobhán; Winstanley, Craig

    2013-01-01

    Pseudomonas aeruginosa is a major opportunistic pathogen in cystic fibrosis (CF) patients and causes a wide range of infections among other susceptible populations. Its inherent resistance to many antimicrobials also makes it difficult to treat infections with this pathogen. Recent evidence has highlighted the diversity of this species, yet despite this, the majority of studies on virulence and pathogenesis focus on a small number of strains. There is a pressing need for a P. aeruginosa reference panel to harmonize and coordinate the collective efforts of the P. aeruginosa research community. We have collated a panel of 43 P. aeruginosa strains that reflects the organism's diversity. In addition to the commonly studied clones, this panel includes transmissible strains, sequential CF isolates, strains with specific virulence characteristics, and strains that represent serotype, genotype or geographic diversity. This focussed panel of P. aeruginosa isolates will help accelerate and consolidate the discovery of virulence determinants, improve our understanding of the pathogenesis of infections caused by this pathogen, and provide the community with a valuable resource for the testing of novel therapeutic agents. PMID:24214409

  5. Spaceflight Effects on Virulence of Pseudomonas Aeruginosa

    NASA Astrophysics Data System (ADS)

    Broadway, S.; Goins, T.; Crandell, C.; Richards, C.; Patel, M.; Pyle, B.

    2008-06-01

    Pseudomonas aeruginosa is an opportunistic pathogen found in the environment. It is known to infect the immunocompromised. The organism has about 25 virulence genes that play different roles in disease processes. Several exotoxin proteins may be produced, including ExoA, ExoS, ExoT and ExoY, and other virulence factors. In spaceflight, possible increased expression of P. aeruginosa virulence proteins could increase health risks for spaceflight crews who experience decreased immunity. Cultures of P. aeruginosa strains PA01 and PA103 grown on orbit on Shuttle Endeavour flight STS-123 vs. static ground controls were used for analysis. The production of ETA was quantitated using an ELISA procedure. Results showed that while flight cultures of PA103 produced slightly more ETA than corresponding ground controls, the opposite was found for PA01. While it appears that spaceflight has little effect on ETA, stimulation of other virulence factors could cause increased virulence of this organism in space flight. Similar increased virulence in spaceflight has been observed for other bacteria. This is important because astronauts may be more susceptible to opportunistic pathogens including P. aeruginosa.

  6. Spontaneous release of lipopolysaccharide by Pseudomonas aeruginosa.

    PubMed Central

    Cadieux, J E; Kuzio, J; Milazzo, F H; Kropinski, A M

    1983-01-01

    Pseudomonas aeruginosa PAO grown in glucose mineral salts medium released lipopolysaccharide which was chemically and immunologically similar to the cellular lipopolysaccharide. In addition, it possessed identical phage E79-inactivating properties. Through neutralization of phage activity and hemolysis inhibition assays, the organism was found to liberate lipopolysaccharide at a constant rate during log-phase growth equivalent to 1.3 to 2.2 ng/10(8) cells over a growth temperature range of 25 to 42 degrees C. At 19 degrees C, a lipopolysaccharide was released which was deficient in phage-inactivating activity but retained its immunological properties. Chemical analysis of lipopolysaccharide extracted from cells grown at 19 degrees C showed a deficiency in the O-side-chain component fucosamine. Gel exclusion chromatography of the polysaccharide fraction derived from lipopolysaccharide isolated from cells grown at 19 degrees C exhibited a decreased content of side-chain polysaccharide as well as a difference in the hexosamine:hexose ratio. The results of sodium dodecyl sulfate-polyacrylamide gel electrophoretic analysis confirmed these results as well as establishing that an essentially normal distribution of side-chain repeating unit lengths were to be found in the 19 degrees C preparation. These results suggest a decrease in the frequency of capping R-form lipopolysaccharide at 19 degrees C. Images PMID:6409883

  7. Nitrite inhibition of denitrification by Pseudomonas fluorescens

    SciTech Connect

    Almeida, J.S.; Julio, S.M.; Reis, M.A.M. |

    1995-05-05

    Using a pure culture of Pseudomonas fluorescens as a model system nitrite inhibition of denitrification was studied. A mineral media with acetate and nitrate as sole electron donor and acceptor, respectively, was used. Results obtained in continuous stirred-tank reactors (CSTR) operated at pH values between 6.6 and 7.8 showed that growth inhibition depended only on the nitrite undissociated fraction concentration (nitrous acid). A mathematical model to describe this dependence is put forward. The maximum nitrous acid concentration compatible with cell growth and denitrification activity was found to be 66 {mu}g N/L. Denitrification activity was partially associated with growth, as described by the Luedeking-Piret equation. However, when the freshly inoculated reactor was operated discontinuously, nitrite accumulation caused growth uncoupling from denitrification activity. The authors suggest that these results can be interpreted considering that (a) nitrous acid acts as a proton uncoupler; and (b) cultures continuously exposed to nitrous acid prevent the uncoupling effect but not the growth inhibition. Examination of the growth dependence on nitrite concentration at pH 7.0 showed that adapted cultures (growth on CSTR) are less sensitive to nitrous acid inhibition than the ones cultivated in batch.

  8. Pseudomonas Aeruginosa: Resistance to the Max

    PubMed Central

    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. Resistance to multiple classes of antimicrobials (multidrug resistance) in particular is increasingly common in P. aeruginosa, with a number of reports of pan-resistant isolates treatable with a single agent, colistin. Acquired resistance in this organism is multifactorial and attributable to chromosomal mutations and the acquisition of resistance genes via horizontal gene transfer. Mutational changes impacting resistance include upregulation of multidrug efflux systems to promote antimicrobial expulsion, derepression of ampC, AmpC alterations that expand the enzyme's substrate specificity (i.e., extended-spectrum AmpC), alterations to outer membrane permeability to limit antimicrobial entry and alterations to antimicrobial targets. Acquired mechanisms contributing to resistance in P. aeruginosa include β-lactamases, notably the extended-spectrum β-lactamases and the carbapenemases that hydrolyze most β-lactams, aminoglycoside-modifying enzymes, and 16S rRNA methylases that provide high-level pan-aminoglycoside resistance. The organism's propensity to grow in vivo as antimicrobial-tolerant biofilms and the occurrence of hypermutator strains that yield antimicrobial resistant mutants at higher frequency also compromise anti-pseudomonal chemotherapy. With limited therapeutic options and increasing resistance will the untreatable P. aeruginosa infection soon be upon us? PMID:21747788

  9. Pseudomonas ribosomal vaccines: preparation, properties, and immunogenicity.

    PubMed Central

    Lieberman, M M

    1978-01-01

    The preparation, properties, and immunogenicity of ribosomal vaccines from Pseudomonas aeruginosa are described. These preparations, containing protein and RNA, were tested for immunogenicity by active immunization of mice and subsequent challenge with homologous, live bacteria. The results demonstrated that vaccines prepared from a majority of serotypes used were immunogenic, i.e., afforded 60 to 100% mouse protection against a challenge inoculum containing 8 to 50 50% lethal doses. In some cases vaccine doses as low as 1 microgram of RNA provided 100% mouse protection. Molecular sieve chromatography of a highly immunogenic ribosomal preparation on Sepharose 4B demonstrated the presence of two molecular weight fractions: (i) peak A, an excluded peak (thus having a molecular weight of at least 2 times 10(7)), and (ii) peak B, considerably retarded, with an elution position corresponding to a molecular weight of about 2.2 X 10(6), approximating that of typical 70S ribosomes. Both peaks A and B were immunogenic; however, the immunogenicity of peak A was greater (i.e., a smaller immunizing dose was required) than that of peak B. Peak A was shown to contain components of lipopolysaccharide in addition to protein and RNA (which comprised 80% of the dry weight of peak A). On the other hand, peak B was shown to be free of lipopolysaccharide, and 100% of its dry weight consisted of protein and RNA. PMID:101464

  10. Pseudomonas biofilms: possibilities of their control.

    PubMed

    Masák, Jan; Čejková, Alena; Schreiberová, Olga; Rezanka, Tomáš

    2014-07-01

    Genus Pseudomonas includes a large number of species that can be encountered in biotechnological processes as well as in the role of serious human or plant pathogens. Pseudomonads easily form biofilms on various types of surfaces. The biofilm phenotype is characterized by an increased resistance to environmental influences including resistance to antibiotics and other disinfectants, causing a number of problems in health care, food industry, and other areas. Considerable attention is therefore paid to the possibilities of eradication/destruction of pseudomonads biofilms both in terms of understanding the mechanisms of biofilm formation and at the level of finding suitable antibiofilm tools applicable in practice. The first part of this review is devoted to an overview of the regulatory mechanisms that are directly or indirectly involved in the formation of biofilm. The most effective approaches to suppressing the formation of biofilm that do not cause the development of resistance are based on the application of substances that interfere with the regulatory molecules or block the appropriate regulatory mechanisms involved in biofilm development by the cells. Pseudomonads biofilm formation is, similar to other microorganisms, a sophisticated process with many regulatory elements. The suppression of this process therefore also requires multiple antibiofilm tools. PMID:24754832

  11. Periplasmic glucans of Pseudomonas syringae pv. syringae.

    PubMed Central

    Talaga, P; Fournet, B; Bohin, J P

    1994-01-01

    We report the initial characterization of glucans present in the periplasmic space of Pseudomonas syringae pv. syringae (strain R32). These compounds were found to be neutral, unsubstituted, and composed solely of glucose. Their size ranges from 6 to 13 glucose units/mol. Linkage studies and nuclear magnetic resonance analyses demonstrated that the glucans are linked by beta-1,2 and beta-1,6 glycosidic bonds. In contrast to the periplasmic glucans found in other plant pathogenic bacteria, the glucans of P. syringae pv. syringae are not cyclic but are highly branched structures. Acetolysis studies demonstrated that the backbone consists of beta-1,2-linked glucose units to which the branches are attached by beta-1,6 linkages. These periplasmic glucans were more abundant when the osmolarity of the growth medium was lower. Thus, P. syringae pv. syringae appears to synthesize periplasmic glucans in response to the osmolarity of the medium. The structural characteristics of these glucans are very similar to the membrane-derived oligosaccharides of Escherichia coli, apart from the neutral character, which contrasts with the highly anionic E. coli membrane-derived oligosaccharides. PMID:7961404

  12. Biodegradation of sulfanilic acid by Pseudomonas paucimobilis.

    PubMed

    Perei, K; Rákhely, G; Kiss, I; Polyák, B; Kovács, K L

    2001-01-01

    An aerobic bacterium, isolated from a contaminated site, was able to degrade sulfanilic acid (4-aminobenzenesulfonic acid) and was identified as Pseudomonas paucimobilis. The isolate could grow on sulfanilic acid (SA) as its sole carbon and nitrogen source and metabolized the target compound to biomass. The bioconversion capacity depended on the sulfanilic acid concentration; greater than 98% elimination of the hazardous compound was achieved at low (10 mM) sulfanilic acid concentration, and the yield was greater than 70% at 50 mM concentration of the contaminant. The maximum conversion rate was 1.5 mmol sulfanilic acid/h per mg wet cells at 30 degrees C. Ca-alginate-phytagel proved a good matrix for immobilization of P. paucimobilis, with essentially unaltered biodegradation activity. Removal of sulfanilic acid from contaminated industrial waste water was demonstrated. SDS-PAGE analysis of the crude extract revealed novel proteins appearing upon induction with sulfanilic acid and related compounds, which indicated alternative degradation mechanisms involving various inducible enzymes.

  13. Extracellular Enzyme Secretion by Pseudomonas lemoignei

    PubMed Central

    Stinson, M. W.; Merrick, J. M.

    1974-01-01

    The ability of succinate to repress the secretion of Pseudomonas lemoignei poly-β-hydroxybutyrate depolymerase was a function of pH. Repression only occurred when the pH of the medium was 7.0 or less. At a higher pH, lack of sensitivity to succinate concentration may have been due to a limited ability to transport succinate. Actively secreting cultures (at pH 7.4) continued to secrete enzyme for approximately 30 min after the pH was rapidly decreased to pH 6.8, even though sufficient succinate was present to repress enzyme synthesis. Similarly, after the addition of rifampin to secreting cultures, there was a 30-min delay before secretion was inhibited. Evidence is presented which suggests that continued secretion may be the result of depolymerase messenger ribonucleic acid accumulation within the cells. Studies with chloramphenicol indicated that de novo protein synthesis is necessary for the secretion of poly-β-hydroxybutyrate depolymerase and that exoenzyme is not released from a preformed pool. Studies with various inhibitors of protein synthesis indicated that synthesis of exoenzyme is 5 to 10 times more susceptible to inhibition than is the synthesis of cell-associated proteins. PMID:4152045

  14. The Pseudomonas fluorescens Siderophore Pyoverdine Weakens Arabidopsis thaliana Defense in Favor of Growth in Iron-Deficient Conditions.

    PubMed

    Trapet, Pauline; Avoscan, Laure; Klinguer, Agnès; Pateyron, Stéphanie; Citerne, Sylvie; Chervin, Christian; Mazurier, Sylvie; Lemanceau, Philippe; Wendehenne, David; Besson-Bard, Angélique

    2016-05-01

    Pyoverdines are siderophores synthesized by fluorescent Pseudomonas spp. Under iron-limiting conditions, these high-affinity ferric iron chelators are excreted by bacteria in the soil to acquire iron. Pyoverdines produced by beneficial Pseudomonas spp. ameliorate plant growth. Here, we investigate the physiological incidence and mode of action of pyoverdine from Pseudomonas fluorescens C7R12 on Arabidopsis (Arabidopsis thaliana) plants grown under iron-sufficient or iron-deficient conditions. Pyoverdine was provided to the medium in its iron-free structure (apo-pyoverdine), thus mimicking a situation in which it is produced by bacteria. Remarkably, apo-pyoverdine abolished the iron-deficiency phenotype and restored the growth of plants maintained in the iron-deprived medium. In contrast to a P. fluorescens C7R12 strain impaired in apo-pyoverdine production, the wild-type C7R12 reduced the accumulation of anthocyanins in plants grown in iron-deficient conditions. Under this condition, apo-pyoverdine modulated the expression of around 2,000 genes. Notably, apo-pyoverdine positively regulated the expression of genes related to development and iron acquisition/redistribution while it repressed the expression of defense-related genes. Accordingly, the growth-promoting effect of apo-pyoverdine in plants grown under iron-deficient conditions was impaired in iron-regulated transporter1 and ferric chelate reductase2 knockout mutants and was prioritized over immunity, as highlighted by an increased susceptibility to Botrytis cinerea This process was accompanied by an overexpression of the transcription factor HBI1, a key node for the cross talk between growth and immunity. This study reveals an unprecedented mode of action of pyoverdine in Arabidopsis and demonstrates that its incidence on physiological traits depends on the plant iron status. PMID:26956666

  15. Genetic Responses Induced in Olive Roots upon Colonization by the Biocontrol Endophytic Bacterium Pseudomonas fluorescens PICF7

    PubMed Central

    Schilirò, Elisabetta; Ferrara, Massimo; Nigro, Franco; Mercado-Blanco, Jesús

    2012-01-01

    Knowledge on the genetic basis underlying interactions between beneficial bacteria and woody plants is still very limited, and totally absent in the case of olive. We aimed to elucidate genetic responses taking place during the colonization of olive roots by the native endophyte Pseudomonas fluorescens PICF7, an effective biocontrol agent against Verticillium wilt of olive. Roots of olive plants grown under non-gnotobiotic conditions were collected at different time points after PICF7 inoculation. A Suppression Subtractive Hybridization cDNA library enriched in induced genes was generated. Quantitative real time PCR (qRT-PCR) analysis validated the induction of selected olive genes. Computational analysis of 445 olive ESTs showed that plant defence and response to different stresses represented nearly 45% of genes induced in PICF7-colonized olive roots. Moreover, quantitative real-time PCR (qRT-PCR) analysis confirmed induction of lipoxygenase, phenylpropanoid, terpenoids and plant hormones biosynthesis transcripts. Different classes of transcription factors (i.e., bHLH, WRKYs, GRAS1) were also induced. This work highlights for the first time the ability of an endophytic Pseudomonas spp. strain to mount a wide array of defence responses in an economically-relevant woody crop such as olive, helping to explain its biocontrol activity. PMID:23144916

  16. Indole-3-acetic acid biosynthesis in the biocontrol strain Pseudomonas fluorescens Psd and plant growth regulation by hormone overexpression.

    PubMed

    Kochar, Mandira; Upadhyay, Ashutosh; Srivastava, Sheela

    2011-05-01

    Pseudomonas fluorescens is an important biological component of agricultural soils that bestows a number of direct and indirect beneficial attributes to the plants. We analyzed the biocontrol strain P. fluorescens Psd for indole-3-acetic acid (IAA) biosynthesis and studied the effect of its consequent manipulation on its plant-growth-promoting (PGP) potential. While the indole pyruvic acid (IPyA) pathway commonly associated with PGP bacteria was lacking, the indole acetamide (IAM) pathway generally observed in phytopathogens was expressed in strain Psd. Overexpression of IAM pathway genes iaaM-iaaH, from Pseudomonas syringae subsp. savastanoi drastically increased IAA levels and showed a detrimental effect on sorghum root development. On the other hand, heterologous expression of the indole-3-pyruvate decarboxylase/phenylpyruvate decarboxylase gene (ipdC/ppdC) of the IPyA pathway from the PGP bacterium Azospirillum brasilense SM led to enhancement of the IAA level. A more favorable effect of this recombinant strain on sorghum root growth and development suggests that metabolic engineering could be used to generate strains with improved PGP function.

  17. Role of the Pseudomonas quinolone signal (PQS) in sensitising Pseudomonas aeruginosa to UVA radiation.

    PubMed

    Pezzoni, Magdalena; Meichtry, Martín; Pizarro, Ramón A; Costa, Cristina S

    2015-01-01

    One of the main stress factors that bacteria face in the environment is solar ultraviolet-A (UVA) radiation, which leads to lethal effects through oxidative damage. The aim of this work was to investigate the role of 2-heptyl-3-hydroxi-4-quinolone (the Pseudomonas quinolone signal or PQS) in the response of Pseudomonas aeruginosa to UVA radiation. PQS is an intercellular quorum sensing signal associated to membrane vesicles which, among other functions, regulates genes related to iron acquisition, forms stable complexes with iron and participates in oxidative phenomena. UVA exposure of the wild-type PAO1 strain and a pqsA mutant unable to produce PQS revealed a sensitising role for this signal. Research into the mechanism involved in this phenomenon revealed that catalase, an essential factor in the UVA defence, is not related to PQS-mediated UVA sensitivity. Absorption of UVA by PQS produced its own photo-degradation, oxidation of the probe 2',7'- dichlorodihydrofluorescein and generation of singlet oxygen and superoxide anion, suggesting that this signal could be acting as an endogenous photosensitiser. The results presented in this study could explain the high sensitivity to UVA of P. aeruginosa when compared to enteric bacteria. PMID:25535873

  18. Pseudomonas cepacia adherence to respiratory epithelial cells is enhanced by Pseudomonas aeruginosa

    SciTech Connect

    Saiman, L.; Cacalano, G.; Prince, A. )

    1990-08-01

    Pseudomonas aeruginosa and Pseudomonas cepacia are both opportunistic pathogens of patients with cystic fibrosis. The binding characteristics of these two species were compared to determine if they use similar mechanisms to adhere to respiratory epithelial cells. P. cepacia 249 was shown to be piliated, but there was no detectable homology between P. aeruginosa pilin gene probes and P. cepacia genomic DNA. P. cepacia and P. aeruginosa did not appear to compete for epithelial receptors. In the presence of purified P. aeruginosa pili, the adherence of 35S-labeled strain 249 to respiratory epithelial monolayers was unaffected, while that of P. aeruginosa PAO1 was decreased by 55%. The binding of P. cepacia 249 and 715j was increased by 2.4-fold and 1.5-fold, respectively, in the presence of an equal inoculum of PAO1. Interbacterial agglutination contributed to the increased adherence of P. cepacia, as the binding of 249 was increased twofold in the presence of irradiated PAO1. PAO1 exoproducts had a marked effect in enhancing the ability of the P. cepacia strains to adhere to the epithelial monolayers. A PAO1 supernatant increased the binding of 249 by eightfold and that of 715j by fourfold. Thus, there appears to be a synergistic relationship between P. aeruginosa and P. cepacia in which PAO1 exoproducts modify the epithelial cell surface, exposing receptors and facilitating increased P. cepacia attachment.

  19. COMPARATIVE TAXONOMY OF CRYSTALLOGENIC STRAINS OF PSEUDOMONAS AERUGINOSA AND PSEUDOMONAS CHLORORAPHIS

    PubMed Central

    Haynes, William C.; Rhodes, Lenora J.

    1962-01-01

    Haynes, William C. (Northern Utilization Research and Development Division, Peoria, Ill.) and Lenora J. Rhodes. Comparative taxonomy of crystallogenic strains of Pseudomonas aeruginosa and Pseudomonas chlororaphis. J. Bacteriol. 84:1080–1084. 1962.—Only 11 of 39 strains received in the Agricultural Research Service Culture Collection under the designation Pseudonomas chlororaphis proved to be authentic; 28 were typical, pyocyanogenic strains of P. aeruginosa. The reason for this disproportionately high rate of misidentification apparently arises from an erroneous belief that the ability to produce green and yellow crystals of chlororaphin and oxychlororaphin is confined to P. chlororaphis. The ability of many strains of P. aeruginosa to do likewise is not well known. Inasmuch as the characteristic is not unique to P. chlororaphis, other criteria are required to distinguish crystallogenic strains of these species. After a taxonomic comparison of 18 strains of P. chlororaphis and 47 crystallogenic strains of P. aeruginosa, it was determined that there are three main distinctions: (i) P. aeruginosa grows well at 42 C but fails to grow upon serial transfer at 5 C, whereas P. chlororaphis fails to grow at 42 C, but grows well at 5 C: (ii) most strains of P. aeruginosa produce pyocyanin, whereas P. chlororaphis strains do not; (iii) P. aeruginosa cells possess only one or two polar flagella, whereas P. chlororaphis usually has at least four, sometimes as many as eight, polar flagella. PMID:13963593

  20. Definition of Plant-Pathogenic Pseudomonas Genomospecies of the Pseudomonas syringae Complex Through Multiple Comparative Approaches.

    PubMed

    Marcelletti, Simone; Scortichini, Marco

    2014-12-01

    A total of 34 phytopathogenic strain genomes belonging to the Pseudomonas syringae species complex and related species, including many pathotype strains, were assessed using average nucleotide identity (ANI) analysis. Their taxonomic relationships were consistently confirmed by the tetranucleotide frequency correlation coefficient (TETRA) values, multilocus sequence typing analysis (MLSA) performed with seven housekeeping genes, using both maximum likelihood and Bayesian methods, and split consensus network analyses. The ANI, MLSA, and split consensus analyses provided consistent and identical results. We confirmed the occurrence of the well-demarcated genomospecies inferred sensu Gardan et al. using DNA-DNA hybridization and ribotyping analyses. However, some P. syringae strains of the pathovars morsprunorum and lachrymans were placed in different genomospecies in our analyses. Genomospecies 1, 2, 4, 6, and 9 resulted well demarcated, whereas strains of genomospecies 3 and 8 had ANI values between 95 and 96% in some cases, confirming that this threshold reveals very closely related species that might represent cases of splitting entities or the convergence of different species to the same ecological niche. This study confirms the robustness of the combination of genomic and phylogenetic approaches in revealing taxonomic relationships among closely related bacterial strains and provides the basis for a further reliable demarcation of the phytopathogenic Pseudomonas species. Within each species, the pathovars might represent distinct ecological units. The possibility of performing extensive and standardized host range and phenotypic tests with many strains of different pathovars can assist phytobacteriologists for better determining the boundaries of these ecological units.

  1. The role of the antimicrobial compound 2,4-diacetylphloroglucinol in the impact of biocontrol Pseudomonas fluorescens F113 on Azospirillum brasilense phytostimulators.

    PubMed

    Couillerot, Olivier; Combes-Meynet, Emeline; Pothier, Joël F; Bellvert, Floriant; Challita, Elita; Poirier, Marie-Andrée; Rohr, René; Comte, Gilles; Moënne-Loccoz, Yvan; Prigent-Combaret, Claire

    2011-06-01

    Pseudomonads producing the antimicrobial metabolite 2,4-diacetylphloroglucinol (Phl) can control soil-borne phytopathogens, but their impact on other plant-beneficial bacteria remains poorly documented. Here, the effects of synthetic Phl and Phl(+) Pseudomonas fluorescens F113 on Azospirillum brasilense phytostimulators were investigated. Most A. brasilense strains were moderately sensitive to Phl. In vitro, Phl induced accumulation of carotenoids and poly-β-hydroxybutyrate-like granules, cytoplasmic membrane damage and growth inhibition in A. brasilense Cd. Experiments with P. fluorescens F113 and a Phl(-) mutant indicated that Phl production ability contributed to in vitro growth inhibition of A. brasilense Cd and Sp245. Under gnotobiotic conditions, each of the three strains, P. fluorescens F113 and A. brasilense Cd and Sp245, stimulated wheat growth. Co-inoculation of A. brasilense Sp245 and Pseudomonas resulted in the same level of phytostimulation as in single inoculations, whereas it abolished phytostimulation when A. brasilense Cd was used. Pseudomonas Phl production ability resulted in lower Azospirillum cell numbers per root system (based on colony counts) and restricted microscale root colonization of neighbouring Azospirillum cells (based on confocal microscopy), regardless of the A. brasilense strain used. Therefore, this work establishes that Phl(+) pseudomonads have the potential to interfere with A. brasilense phytostimulators on roots and with their plant growth promotion capacity.

  2. Increased Sheep Lung Vascular Permeability Caused by Pseudomonas Bacteremia

    PubMed Central

    Brigham, Kenneth L.; Woolverton, William C.; Blake, Lynn H.; Staub, Norman C.

    1974-01-01

    In awake sheep, we compared the responses of lung lymph flow and lymph and plasma protein concentrations to steady state elevations of pulmonary vascular pressures made by inflating a left atrial balloon with those after an intravenous infusion of 105-1010Pseudomonas aeruginosa. Lymph flow increased when pressure was increased, but lymph-plasma protein concentration ratios always fell and lymph protein flow (lymph flow × lymph protein concentration) increased only slightly. After Pseudomonas, sheep had transient chills, fever, leukopenia, hypoxemia, increased pulmonary artery pressure and lymph flow and decreased left atrial pressure and lymph protein concentration, 3-5 h after Pseudomonas, when vascular pressures and lymph protein concentrations had returned to near base line, lymph flow increased further to 3-10 times base line and remained at a steady level for many hours. During this steady state period, lymph-plasma protein concentration ratios were similar to base line and lymph protein flow was higher than in the increased pressure studies. Two sheep died of pulmonary edema 7 and 9 h after Pseudomonas, but in 16 studies, five other sheep appeared well during the period of highest lymph flow and all variables returned to base line in 24-72 h. Six serial indicator dilution lung water studies in five sheep changed insignificantly from base line after Pseudomonas. Postmortem lung water was high in the two sheep dead of pulmonary edema and one other, but six sheep killed 1-6 h after Pseudomonas had normal lung water. Because of the clear difference between the effects of increased pressure and Pseudomonas on lymphplasma protein concentration ratios and lymph protein flow, we conclude that Pseudomonas causes a prolonged increase in lung vessel permeability to protein. Because we saw lung lymph flow as high as 10 times base line without pulmonary edema, we conclude that lung lymphatics are a sensitive high-capacity mechanism for removing excess filtered fluid. An

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

    PubMed

    Nwinyi, Obinna C; Ajayi, Oluseyi O; Amund, Olukayode O

    2016-01-01

    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 94ppm 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 R(2)=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. PMID:27245129

  4. Flagellin gene sequence variation in the genus Pseudomonas.

    PubMed

    Bellingham, N F; Morgan, J A; Saunders, J R; Winstanley, C

    2001-07-01

    Flagellin gene (fliC) sequences from 18 strains of Pseudomonas sensu stricto representing 8 different species, and 9 representative fliC sequences from other members of the gamma sub-division of proteobacteria, were compared. Analysis was performed on N-terminal, C-terminal and whole fliC sequences. The fliC analyses confirmed the inferred relationship between P. mendocina, P. oleovorans and P. aeruginosa based on 16S rRNA sequence comparisons. In addition, the analyses indicated that P. putida PRS2000 was closely related to P. fluorescens SBW25 and P. fluorescens NCIMB 9046T, but suggested that P. putida PaW8 and P. putida PRS2000 were more closely related to other Pseudomonas spp. than they were to each other. There were a number of inconsistencies in inferred evolutionary relationships between strains, depending on the analysis performed. In particular, whole flagellin gene comparisons often differed from those obtained using N- and C-terminal sequences. However, there were also inconsistencies between the terminal region analyses, suggesting that phylogenetic relationships inferred on the basis of fliC sequence should be treated with caution. Although the central domain of fliC is highly variable between Pseudomonas strains, there was evidence of sequence similarities between the central domains of different Pseudomonas fliC sequences. This indicates the possibility of recombination in the central domain of fliC genes within Pseudomonas species, and between these genes and those from other bacteria. PMID:11518318

  5. Biosurfactant production in sugar beet molasses by some Pseudomonas spp.

    PubMed

    Onbasli, Dilsad; Aslim, Belma

    2009-01-01

    In this study rhamnolipid biosurfactant production was investigated in eighteen strains of Pseudomonas spp.. Rhamnolipid by these strains was determined by a spectrophotometric method in nutrient broth medium (NB). From the 18 strains screened, two Pseudomonas strains (Pseudomonas luteola B17 and Pseudomonas putida B12) which had produced the highest percentage yield of rhamnolipid were examined for rhamnolipid production at different incubation times (24, 48 and 72 hr) and different sugar beet molasses concentrations [1-5% w/v concentration (1-5 g molasses/100 ml water)]. The rhamnolipid production increased with the increase in the concentration of molasses and maximum production occurred when 5 % (w/v) of molasses were used. At the same time, maximum rhamnolipid production occurred after 72 hr of incubation. When the amount of rhamnolipid produced at different incubation times (24, 48 and 72 hr) and with different concentrations of molasses [1-5 % w/v concentration (1-5 g molasses/100 ml water)] by Pseudomonas spp.; was compared, no significant difference in amount of production was seen. These studies show that the waste product from sugar industry may be suggested for important biotechnological processes such as rhamnolipid production.

  6. Sequence heterogeneity of the ferripyoverdine uptake (fpvA), but not the ferric uptake regulator (fur), genes among strains of the fluorescent pseudomonads Pseudomonas aeruginosa, Pseudomonas aureofaciens, Pseudomonas fluorescens and Pseudomonas putida.

    PubMed

    Thupvong, T; Wiideman, A; Dunn, D; Oreschak, K; Jankowicz, B; Doering, J; Castignetti, D

    1999-09-01

    Pseudomonas aeruginosa, Pseudomonas aureofaciens, Pseudomonas fluorescens and Pseudomonas putida are of importance to medicine, agriculture and biocycling. These microbes acquire ferric ion via the use of the siderophores pyochelin and the family known as the pyoverdines or pseudobactins. The ferric uptake regulator (fur) gene is responsible, at least in part, for the regulation of siderophore synthesis and uptake in P. aeruginosa. To determine whether the organisms contain single or multiple homologues of the siderophore-related genes fpvA (ferripyoverdine uptake) and fur, and whether these homologues displayed sequence heterogeneity, their chromosomal DNAs were probed with fur and fpvA sequences. As a representative of a non-fluorescent pseudomonad, the bacterium Burkholderia (Pseudomonas) cepacia was also examined. The pseudomonads all contained fpvA- and fur-like homologues, and heterogeneity was observed among the different species. The presence of two or more fpvA-like genes is indicated in all of the fluorescent pseudomonads surveyed. In contrast, B. cepacia DNA either did not hybridize to these probes, or did so only very weakly, suggesting that fur- and fpvA-like homologues are either absent or significantly different in B. cepacia compared to the fluorescent pseudomonads examined.

  7. 26 CFR 1.674(a)-1 - Power to control beneficial enjoyment; scope of section 674.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 8 2010-04-01 2010-04-01 false Power to control beneficial enjoyment; scope of... TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES Grantors and Others Treated As Substantial Owners § 1.674(a)-1 Power to control beneficial enjoyment; scope of section 674. (a) Under section 674,...

  8. Electrostatic beneficiation of coal. Quarterly technical progress report, April 1, 1996--June 30, 1996

    SciTech Connect

    Mazumder, M.K.; Lindquist, D.; Tennal, K.B.

    1996-07-01

    Progress reports are presented for the following: modification to the electrostatic separator; review of DOE specifications for minimum beneficiation and calculations of grinding requirements based on washability; two-pass beneficiation; analysis of different sieve fractions; measurement of charge to mass ratio as a function of height of deposition; and charging of coal against different materials.

  9. Kinetics of fly ash beneficiation by carbon burnout: Quarterly report, October 1-December 31, 1997

    SciTech Connect

    1997-12-31

    To investigate the kinetics of beneficiation of fly ash by carbon burnout The project is a joint venture between Delmarva Power, a power generating company on the eastern shore of Maryland, and the University of Maryland Eastern Shore. The studies have focused on the beneficiation of fly ash by carbon burnout.

  10. Silicone glycol collectors in the beneficiation of fine coal by froth flotation

    SciTech Connect

    Owen, M.J.

    1985-07-02

    A froth flotation process for the beneficiation of fine coal is disclosed which employs as a collector a water-dispersible polyorganosiloxane or a mixture of water-dispersible polyorganosiloxanes which contain organic radicals selected from the group consisting of polyethylene oxide and polypropylene oxide radicals. The process of this invention is especially useful for the beneficiation of difficult-to-float fine coals.

  11. 75 FR 11207 - Policy Statement on Obtaining and Retaining Beneficial Ownership Information for Anti-Money...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-10

    ... this provision. Special Due Diligence Programs for Certain Foreign Accounts, 72 FR 44768-44775 (August... COMMISSION Policy Statement on Obtaining and Retaining Beneficial Ownership Information for Anti-Money... retaining beneficial ownership information for anti-money laundering purposes. DATES: Effective Date:...

  12. The Regulatory Network of Pseudomonas aeruginosa

    PubMed Central

    2011-01-01

    Background Pseudomonas aeruginosa is an important bacterial model due to its metabolic and pathogenic abilities, which allow it to interact and colonize a wide range of hosts, including plants and animals. In this work we compile and analyze the structure and organization of an experimentally supported regulatory network in this bacterium. Results The regulatory network consists of 690 genes and 1020 regulatory interactions between their products (12% of total genes: 54% sigma and 16% of transcription factors). This complex interplay makes the third largest regulatory network of those reported in bacteria. The entire network is enriched for activating interactions and, peculiarly, self-activation seems to occur more prominent for transcription factors (TFs), which contrasts with other biological networks where self-repression is dominant. The network contains a giant component of 650 genes organized into 11 hierarchies, encompassing important biological processes, such as, biofilms formation, production of exopolysaccharide alginate and several virulence factors, and of the so-called quorum sensing regulons. Conclusions The study of gene regulation in P. aeruginosa is biased towards pathogenesis and virulence processes, all of which are interconnected. The network shows power-law distribution -input degree -, and we identified the top ten global regulators, six two-element cycles, the longest paths have ten steps, six biological modules and the main motifs containing three and four elements. We think this work can provide insights for the design of further studies to cover the many gaps in knowledge of this important bacterial model, and for the design of systems strategies to combat this bacterium. PMID:22587778

  13. Cryptic transposable phages of Pseudomonas aeruginosa

    SciTech Connect

    Krylov, V.N.; Mit`kina, L.N.; Pleteneva, E.A.; Aleshin, V.V.

    1995-11-01

    Frequencies of nucleotide sequences homologous to phage transposons (PT) of two species, D3112 and B3, were assessed in genomes of natural Pseudomonas aeruginosa strains by the dot-blot hybridization method. These strains were incapable of liberating viable phages on a lawn of the PA01 standard indicator strain of P. aeruginosa. It was shown that the homologies detected belong to two groups, high and intermediate, with respect to homology level. Homology patterns were classified as high when they provided signals comparable to those for hybridization in a positive control; patterns were classified as intermediate when the hybridization level was higher than the background level, but lower than in the positive control. Homologous PT sequences were designated as cryptic PT. Intact cryptic PT prophages were shown to exist in genomes of particular natural strains manifesting a higher level of hybridization. However, the growth of these phages was limited by the restriction system of strain PA01. It is possible to isolate strains maintaining the growth of some cryptic PT. These strains differed from P. aeruginosa with respect to the specificity of the restriction and modification system. Nevertheless, in most cases, the attempt to identify a novel host capable of maintaining growth of a cryptic PT failed. Natural strains often carry cryptic PT related to both known PT species, D3112 and B3. The frequency of cryptic PT is extremely high, reaching 30% in strains with a high level of homology only and up to 50% in all strains exhibiting homology. This high PT frequency is assumed to be associated with the considerable variation of P. aeruginosa. 15 refs., 1 fig., 2 tabs.

  14. Ambroxol interferes with Pseudomonas aeruginosa quorum sensing.

    PubMed

    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. PMID:20580207

  15. Pseudomonas fluorescens' view of the periodic table.

    PubMed

    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.

  16. Aflatoxin B₁ degradation by a Pseudomonas strain.

    PubMed

    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.

  17. Ambroxol interferes with Pseudomonas aeruginosa quorum sensing.

    PubMed

    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.

  18. Pseudomonas aeruginosa Genomic Structure and Diversity

    PubMed Central

    Klockgether, Jens; Cramer, Nina; Wiehlmann, Lutz; Davenport, Colin F.; Tümmler, Burkhard

    2011-01-01

    The Pseudomonas aeruginosa genome (G + C content 65–67%, size 5.5–7 Mbp) is made up of a single circular chromosome and a variable number of plasmids. Sequencing of complete genomes or blocks of the accessory genome has revealed that the genome encodes a large repertoire of transporters, transcriptional regulators, and two-component regulatory systems which reflects its metabolic diversity to utilize a broad range of nutrients. The conserved core component of the genome is largely collinear among P. aeruginosa strains and exhibits an interclonal sequence diversity of 0.5–0.7%. Only a few loci of the core genome are subject to diversifying selection. Genome diversity is mainly caused by accessory DNA elements located in 79 regions of genome plasticity that are scattered around the genome and show an anomalous usage of mono- to tetradecanucleotides. Genomic islands of the pKLC102/PAGI-2 family that integrate into tRNALys or tRNAGly genes represent hotspots of inter- and intraclonal genomic diversity. The individual islands differ in their repertoire of metabolic genes that make a large contribution to the pangenome. In order to unravel intraclonal diversity of P. aeruginosa, the genomes of two members of the PA14 clonal complex from diverse habitats and geographic origin were compared. The genome sequences differed by less than 0.01% from each other. One hundred ninety-eight of the 231 single nucleotide substitutions (SNPs) were non-randomly distributed in the genome. Non-synonymous SNPs were mainly found in an integrated Pf1-like phage and in genes involved in transcriptional regulation, membrane and extracellular constituents, transport, and secretion. In summary, P. aeruginosa is endowed with a highly conserved core genome of low sequence diversity and a highly variable accessory genome that communicates with other pseudomonads and genera via horizontal gene transfer. PMID:21808635

  19. No vacancy: how beneficial microbes cooperate with immunity to provide colonization resistance to pathogens.

    PubMed

    Sassone-Corsi, Martina; Raffatellu, Manuela

    2015-05-01

    The mammalian intestine harbors a community of trillions of microbes, collectively known as the gut microbiota, which coevolved with the host in a mutually beneficial relationship. Among the numerous gut microbial species, certain commensal bacteria are known to provide health benefits to the host when administered in adequate amounts and, as such, are labeled "probiotics." We review some of the mechanisms by which probiotics and other beneficial commensals provide colonization resistance to pathogens. The battle for similar nutrients and the bacterial secretion of antimicrobials provide a direct means of competition between beneficial and harmful microbes. Beneficial microbes can also indirectly diminish pathogen colonization by stimulating the development of innate and adaptive immunity, as well as the function of the mucosal barrier. Altogether, we gather and present evidence that beneficial microbes cooperate with host immunity in an effort to shut out pathogens.

  20. Risk assessment of Pseudomonas aeruginosa in water.

    PubMed

    Mena, Kristina D; Gerba, Charles P

    2009-01-01

    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 inhaling aerosols.

  1. Modified Pseudomonas agar: new differential medium for the detection/enumeration of Pseudomonas aeruginosa in mineral water.

    PubMed

    Ramalho, Rita; Cunha, Joaquim; Teixeira, Paula; Gibbs, Paul A

    2002-03-01

    Pseudomonas aeruginosa has been implicated as a foodborne and waterborne pathogen and is now considered a primary infectious agent. In the present study, the survival of P. aeruginosa inoculated in mineral water was evaluated by drop counts on Pseudomonas Agar Base (PAB), PAB with CN supplement X107, PAB with cetrimide, PAB with nalidixic acid, and these media with added FeSO(4). Initial counts, before starvation, were the same in all media tested. Following this period, P. aeruginosa became sensitive to PAB with added cetrimide. The addition of FeSO(4) did not improve the recovery of stressed P. aeruginosa but gave colonies a typical dark brown colour being easily differentiated from other species that can grow at 42 degrees C. The modified Pseudomonas agar medium was also tested with several P. aeruginosa strains, other species of Pseudomonas, and other genera. Only P. aeruginosa strains (pyocyanin positive) produced the typical colonies. Our results demonstrate that Pseudomonas agar with ferrous sulphate, used for the differentiation of P. aeruginosa colonies, and nalidixic acid, used as an inhibitor of Gram-positive bacteria, might be a useful medium for the detection of injured P. aeruginosa in mineral water. PMID:11777584

  2. Biotransformation of Tributyltin chloride by Pseudomonas stutzeri strain DN2

    PubMed Central

    Khanolkar, Dnyanada S.; Naik, Milind Mohan; Dubey, Santosh Kumar

    2014-01-01

    A bacterial isolate capable of utilizing tributyltin chloride (TBTCl) as sole carbon source was isolated from estuarine sediments of west coast of India and identified as Pseudomonas stutzeri based on biochemical tests and Fatty acid methyl ester (FAME) analysis. This isolate was designated as strain DN2. Although this bacterial isolate could resist up to 3 mM TBTCl level, it showed maximum growth at 2 mM TBTCl in mineral salt medium (MSM). Pseudomonas stutzeri DN2 exposed to 2 mM TBTCl revealed significant alteration in cell morphology as elongation and shrinkage in cell size along with roughness of cell surface. FTIR and NMR analysis of TBTCl degradation product extracted using chloroform and purified using column chromatography clearly revealed biotransformation of TBTCl into Dibutyltin dichloride (DBTCl2) through debutylation process. Therefore, Pseudomonas stutzeri strain DN2 may be used as a potential bacterial strain for bioremediation of TBTCl contaminated aquatic environmental sites. PMID:25763027

  3. Subtilase SprP exerts pleiotropic effects in Pseudomonas aeruginosa.

    PubMed

    Pelzer, Alexander; Polen, Tino; Funken, Horst; Rosenau, Frank; Wilhelm, Susanne; Bott, Michael; Jaeger, Karl-Erich

    2014-02-01

    The open reading frame PA1242 in the genome of Pseudomonas aeruginosa PAO1 encodes a putative protease belonging to the peptidase S8 family of subtilases. The respective enzyme termed SprP consists of an N-terminal signal peptide and a so-called S8 domain linked by a domain of unknown function (DUF). Presumably, this DUF domain defines a discrete class of Pseudomonas proteins as homologous domains can be identified almost exclusively in proteins of the genus Pseudomonas. The sprP gene was expressed in Escherichia coli and proteolytic activity was demonstrated. A P. aeruginosa ∆sprP mutant was constructed and its gene expression pattern compared to the wild-type strain by genome microarray analysis revealing altered expression levels of 218 genes. Apparently, SprP is involved in regulation of a variety of different cellular processes in P. aeruginosa including pyoverdine synthesis, denitrification, the formation of cell aggregates, and of biofilms. PMID:24376018

  4. Biological manganese oxidation by Pseudomonas putida in trickling filters.

    PubMed

    McKee, Kyle P; Vance, Cherish C; Karthikeyan, Raghupathy

    2016-01-01

    Biological oxidation has been researched as a viable alternative for treating waters with high manganese (Mn) concentrations, typically found in mine drainage or in some geological formations. In this study, laboratory-scale trickling filters were constructed to compare the Mn removal efficiency between filters inoculated with the Mn oxidizing bacteria, Pseudomonas putida, and filters without inoculation. Manganese oxidation and removal was found to be significantly greater in trickling filters with Pseudomonas putida after startup times of only 48 h. Mn oxidation in Pseudomonas putida inoculated trickling filters was up to 75% greater than non-inoculated filters. One-dimensional advective-dispersive models were formulated to describe the transport of Mn in trickling filter porous media. Based on the experimental transport parameters obtained, the model predicted that a filter depth of only 16 cm is needed to reduce influent concentration of 10 mg L(-1) to 0.05 mg L(-1).

  5. Microbial degradation of quinoline and methylquinolines. [Pseudomonas aeruginosa

    SciTech Connect

    Aislabie, J.; Bej, A.K.; Hurst, H.; Rothenburger, S.; Atlas, R.M. )

    1990-02-01

    Several bacterial cultures were isolated that are able to degrade quinoline and to transform or to degrade methylquinolines. The degradation of quinoline by strains of Pseudomonas aeruginosa QP and Pseudomonas. putida QP produced hydroxyquinolines, a transient pink compound, and other undetermined products. The quinoline-degrading strains of P. aeruginosa QP and P. putida QP hydroxylated a limited number of methylquinolines but could not degrade them, nor could they transform 2-methylquinoline, isoquinoline, or pyridine. Another pseudomonad, Pseudomonas sp. strain MQP, was isolated that could degrade 2-methylquinoline. P. aeruginosa QP was able to degrade or to transform quinoline and a few methylquinolines in a complex heterocyclic nitrogen-containing fraction of a shale oil. All of the quinoline- and methylquinoline-degrading strains have multiple plasmids including a common 250-kilobase plasmid. The 225-, 250-, and 320-kilobase plasmids of the P. aeruginosa QP strain all contained genes involved in quinoline metabolism.

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

    PubMed

    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.

  7. Genetically enhanced cellulase production in Pseudomonas cellulosa using recombinant DNA technology

    DOEpatents

    Dees, H. Craig

    1999-01-01

    An enhanced strain of Pseudomonas celllulosa was obtained by introducing a recombinant genetic construct comprising a heterologous cellulase gene operably connected to a promoter into ATCC 55702, mutagenizing the transformants by treatment with MNNG, and selecting a high cellulase producing transformant. The transformant, designated Pseudomonas cellulosa ATCC XXXX, exhibits enhanced levels of cellulase production relative to the untransformed Pseudomonas cellulosa strain #142 ATCC 55702.

  8. identification of Pseudomonas spp. as amoeba-resistant microorganisms in isolates of Acanthamoeba.

    PubMed

    José Maschio, Vinicius; Corção, Gertrudes; Rott, Marilise Brittes

    2015-01-01

    Acanthamoeba is a "Trojan horse" of the microbial world. The aim of this study was to identify the presence of Pseudomonas as an amoeba-resistant microorganism in 12 isolates of Acanthamoeba. All isolates showed the genus Pseudomonas spp. as amoeba-resistant microorganisms. Thus, one can see that the Acanthamoeba isolates studied are hosts of Pseudomonas.

  9. IDENTIFICATION OF Pseudomonas spp. AS AMOEBA-RESISTANT MICROORGANISMS IN ISOLATES OF Acanthamoeba

    PubMed Central

    Maschio, Vinicius José; Corção, Gertrudes; Rott, Marilise Brittes

    2015-01-01

    Acanthamoeba is a “Trojan horse” of the microbial world. The aim of this study was to identify the presence of Pseudomonas as an amoeba-resistant microorganism in 12 isolates of Acanthamoeba. All isolates showed the genus Pseudomonas spp. as amoeba-resistant microorganisms. Thus, one can see that the Acanthamoeba isolates studied are hosts of Pseudomonas. PMID:25651331

  10. Can beneficial ends justify lying? Neural responses to the passive reception of lies and truth-telling with beneficial and harmful monetary outcomes.

    PubMed

    Yin, Lijun; Weber, Bernd

    2016-03-01

    Can beneficial ends justify morally questionable means? To investigate how monetary outcomes influence the neural responses to lying, we used a modified, cheap talk sender-receiver game in which participants were the direct recipients of lies and truthful statements resulting in either beneficial or harmful monetary outcomes. Both truth-telling (vs lying) as well as beneficial (vs harmful) outcomes elicited higher activity in the nucleus accumbens. Lying (vs truth-telling) elicited higher activity in the supplementary motor area, right inferior frontal gyrus, superior temporal sulcus and left anterior insula. Moreover, the significant interaction effect was found in the left amygdala, which showed that the monetary outcomes modulated the neural activity in the left amygdala only when truth-telling rather than lying. Our study identified a neural network associated with the reception of lies and truth, including the regions linked to the reward process, recognition and emotional experiences of being treated (dis)honestly.

  11. Pseudomonas chengduensis sp. nov., isolated from landfill leachate.

    PubMed

    Tao, Yong; Zhou, Yan; He, Xiaohong; Hu, Xiaohong; Li, Daping

    2014-01-01

    Strain MBR(T) was isolated from landfill leachate in a solid-waste disposal site in Chengdu, Sichuan, China. An analysis of 16S rRNA gene sequences revealed that the isolate was closely related to members of the genus Pseudomonas, sharing the highest sequence similarities with Pseudomonas toyotomiensis HT-3(T) (99.8 %), Pseudomonas alcaliphila AL15-21(T) (99.7 %) and Pseudomonas oleovorans ATCC 8062(T) (99.4 %). Multi-locus sequence analysis based on three housekeeping genes (gyrB, rpoB and rpoD) provided higher resolution at the species level than that based on 16S rRNA gene sequences, which was further confirmed by less than 70 % DNA-DNA relatedness between the new isolate and P. toyotomiensis HT-3(T) (61.3 %), P. alcaliphila AL15-21(T) (51.5 %) and P. oleovorans ATCC 8062(T) (57.8 %). The DNA G+C content of strain MBR(T) was 61.9 mol% and the major ubiquinone was Q-9. The major cellular fatty acids (>10 %) were C18 : 1ω7c and/or C18 : 1ω6c, C16 : 0, and C16 : 1ω7c and/or C16 : 1ω6c. Polyphasic analysis indicates that strain MBR(T) represents a novel species of the genus Pseudomonas, for which the name Pseudomonas chengduensis sp. nov. is proposed. The type strain is MBR(T) ( = CGMCC 2318(T) = DSM 26382(T)). PMID:24021726

  12. Diversity and antibiotic resistance in Pseudomonas spp. from drinking water.

    PubMed

    Vaz-Moreira, Ivone; Nunes, Olga C; Manaia, Célia M

    2012-06-01

    Pseudomonas spp. are common inhabitants of aquatic environments, including drinking water. Multi-antibiotic resistance in clinical isolates of P. aeruginosa is widely reported and deeply characterized. However, the information regarding other species and environmental isolates of this genus is scant. This study was designed based on the hypothesis that members of the genus Pseudomonas given their high prevalence, wide distribution in waters and genetic plasticity can be important reservoirs of antibiotic resistance in drinking water. With this aim, the diversity and antibiotic resistance phenotypes of Pseudomonas isolated from different drinking water sources were evaluated. The genotypic diversity analyses were based on six housekeeping genes (16S rRNA, rpoD, rpoB, gyrB, recA and ITS) and on pulsed field gel electrophoresis. Susceptibility to 21 antibiotics of eight classes was tested using the ATB PSE EU (08) and disk diffusion methods. Pseudomonas spp. were isolated from 14 of the 32 sampled sites. A total of 55 non-repetitive isolates were affiliated to twenty species. Although the same species were isolated from different sampling sites, identical genotypes were never observed in distinct types of water (water treatment plant/distribution system, tap water, cup fillers, biofilm, and mineral water). In general, the prevalence of antibiotic resistance was low and often the resistance patterns were related with the species and/or the strain genotype. Resistance to ticarcillin, ticarcillin with clavulanic acid, fosfomycin and cotrimoxazol were the most prevalent (69-84%). No resistance to piperacillin, levofloxacin, ciprofloxacin, tetracycline, gentamicin, tobramycin, amikacin, imipenem or meropenem was observed. This study demonstrates that Pseudomonas spp. are not so widespread in drinking water as commonly assumed. Nevertheless, it suggests that water Pseudomonas can spread acquired antibiotic resistance, preferentially via vertical transmission.

  13. Pseudomonas zhaodongensis sp. nov., isolated from saline and alkaline soils.

    PubMed

    Zhang, Lei; Pan, Yuanyuan; Wang, Kaibiao; Zhang, Xiaoxia; Zhang, Cheng; Zhang, Shuang; Fu, Xiaowei; Jiang, Juquan

    2015-03-01

    Strain NEAU-ST5-21(T) was isolated from saline and alkaline soils in Zhaodong City, Heilongjiang Province, China. It was aerobic, Gram-stain-negative, rod-shaped and motile with a polar flagellum. It produced yellow-orange colonies with a smooth surface, and grew in the presence of 0-5 % (w/v) NaCl (optimum 0 %, w/v), at temperatures of 20-40 °C (optimum 28 °C) and at pH 7-11 (optimum pH 7). Phylogenetic analyses based on the separate 16S rRNA gene sequences and concatenated 16S rRNA, gyrB and rpoD gene sequences indicated that strain NEAU-ST5-21(T) belongs to the genus Pseudomonas in the class Gammaproteobacteria. The most closely related species is Pseudomonas xanthomarina, whose type strain (KMM 1447(T)) showed gene sequence similarities of 99.0 % for 16S rRNA, 81.8 % for gyrB and 85.0 % for rpoD with strain NEAU-ST5-21(T). DNA-DNA hybridization values between strain NEAU-ST5-21(T) and P. xanthomarina DSM 18231(T), Pseudomonas kunmingensis CGMCC 1.12273(T), Pseudomonas stutzeri DSM 5190(T), Pseudomonas oleovorans subsp. lubricantis DSM 21016(T), Pseudomomas chengduensis CGMCC 2318(T), Pseudomonas alcaliphila DSM 17744(T) and Pseudomonas toyotomiensis DSM 26169(T) were 52±0 % to 25±2 %. The DNA G+C content of strain NEAU-ST5-21(T) was 65 mol%. The major fatty acids (>10 %) were C18 : 1ω7c and/or C18 : 1ω6c, C16 : 1ω7c and/or C16 : 1ω6c and C16 : 0, the predominant respiratory quinone was ubiquinone 9, and polar lipids consisted of diphosphatidylglycerol, phosphatidylethanolamine, one unknown phospholipid, phosphatidylglycerol, one unknown aminolipid, one unknown lipid and a glycolipid. The proposed name is Pseudomonas zhaodongensis sp. nov., NEAU-ST5-21(T) ( = ACCC 06362(T) = DSM 27559(T)) being the type strain. PMID:25574037

  14. Pseudomonas corneal ulcer. The causative role of contaminated eye cosmetics.

    PubMed

    Reid, F R; Wood, T O

    1979-09-01

    The clinical significance of contaminated ocular cosmetics is illustrated by the case of a 47-year-old woman in whom a Pseudomonas corneal ulcer developed immediately after she sustained minor corneal trauma with a mascara applicator. Pseudomonas aeruginosa was cultured from the corneal ulcer and the mascara. In addition to the causative role in acute corneal ulcers, contaminated eye cosmetics contribute to chronic external eye infections. Retail eye cosmetics are typically free of contamination when purchased. The inoculation of the cosmetic occurs during normal use. PMID:112953

  15. Community-based interference against integration of Pseudomonas aeruginosa into human salivary microbial biofilm.

    PubMed

    He, X; Hu, W; He, J; Guo, L; Lux, R; Shi, W

    2011-12-01

    As part of the human gastrointestinal tract, the oral cavity represents a complex biological system and harbors diverse bacterial species. Unlike the gut microbiota, which is often considered a health asset, studies of the oral commensal microbiota have been largely limited to their implication in oral conditions such as dental caries and periodontal disease. Less emphasis has been given to their potential beneficial roles, especially the protective effects against oral colonization by foreign or pathogenic bacteria. In this study, we used salivary microbiota derived from healthy human subjects to investigate protective effects against colonization and integration of Pseudomonas aeruginosa, an opportunistic bacterial pathogen, into developing or pre-formed salivary biofilms. When co-cultivated in saliva medium, P. aeruginosa persisted in the planktonic phase, but failed to integrate into the salivary microbial community during biofilm formation. Furthermore, in saliva medium supplemented with sucrose, the oral microbiota inhibited the growth of P. aeruginosa by producing lactic acid. More interestingly, while pre-formed salivary biofilms were able to prevent P. aeruginosa colonization, the same biofilms recovered from mild chlorhexidine gluconate treatment displayed a shift in microbial composition and showed a drastic reduction in protection. Our study indicates that normal oral communities with balanced microbial compositions could be important in effectively preventing the integration of foreign or pathogenic bacterial species, such as P. aeruginosa. PMID:22053962

  16. Physiological framework for the regulation of quorum sensing-dependent public goods in Pseudomonas aeruginosa.

    PubMed

    Mellbye, Brett; Schuster, Martin

    2014-03-01

    Many bacteria possess cell density-dependent quorum-sensing (QS) systems that often regulate cooperative secretions involved in host-microbe or microbe-microbe interactions. These secretions, or "public goods," are frequently coregulated by stress and starvation responses. Here we provide a physiological rationale for such regulatory complexity in the opportunistic pathogen Pseudomonas aeruginosa. Using minimal-medium batch and chemostat cultures, we comprehensively characterized specific growth rate-limiting macronutrients as key triggers for the expression of extracellular enzymes and metabolites directly controlled by the las and rhl QS systems. Expression was unrelated to cell density, depended on the secreted product's elemental composition, and was induced only when the limiting nutrient was not also a building block of the product; rhl-dependent products showed the strongest response, caused by the largely las-independent induction of the regulator RhlR and its cognate signal. In agreement with the prominent role of the rhl system, slow growth inverted the las-to-rhl signal ratio, previously considered a characteristic distinguishing between planktonic and biofilm lifestyles. Our results highlight a supply-driven, metabolically prudent regulation of public goods that minimizes production costs and thereby helps stabilize cooperative behavior. Such regulation would be beneficial for QS-dependent public goods that act broadly and nonspecifically, and whose need cannot always be accurately assessed by the producing cell. Clear differences in the capacities of the las and rhl systems to integrate starvation signals help explain the existence of multiple QS systems in one cell.

  17. Genes as Early Responders Regulate Quorum-Sensing and Control Bacterial Cooperation in Pseudomonas aeruginosa

    PubMed Central

    Zhao, Kelei; Li, Yi; Yue, Bisong; Wu, Min

    2014-01-01

    Quorum-sensing (QS) allows bacterial communication to coordinate the production of extracellular products essential for population fitness at higher cell densities. It has been generally accepted that a significant time duration is required to reach appropriate cell density to activate the relevant quiescent genes encoding these costly but beneficial public goods. Which regulatory genes are involved and how these genes control bacterial communication at the early phases are largely un-explored. By determining time-dependent expression of QS-related genes of the opportunistic pathogen Pseudomonas aerugionsa, we show that the induction of social cooperation could be critically influenced by environmental factors to optimize the density of population. In particular, small regulatory RNAs (RsmY and RsmZ) serving as early responders, can promote the expression of dependent genes (e.g. lasR) to boost the synthesis of intracellular enzymes and coordinate instant cooperative behavior in bacterial cells. These early responders, acting as a rheostat to finely modulate bacterial cooperation, which may be quickly activated under environment threats, but peter off when critical QS dependent genes are fully functional for cooperation. Our findings suggest that RsmY and RsmZ critically control the timing and levels of public goods production, which may have implications in sociomicrobiology and infection control. PMID:25006971

  18. Bacteriophage-based therapy in cystic fibrosis-associated Pseudomonas aeruginosa infections: rationale and current status.

    PubMed

    Hraiech, Sami; Brégeon, Fabienne; Rolain, Jean-Marc

    2015-01-01

    Pulmonary infections involving Pseudomonas aeruginosa are among the leading causes of the deterioration of the respiratory status of cystic fibrosis (CF) patients. The emergence of multidrug-resistant strains in such populations, favored by iterative antibiotic cures, has led to the urgent need for new therapies. Among them, bacteriophage-based therapies deserve a focus. One century of empiric use in the ex-USSR countries suggests that bacteriophages may have beneficial effects against a large range of bacterial infections. Interest in bacteriophages has recently renewed in Western countries, and the in vitro data available suggest that bacteriophage-based therapy may be of significant interest for the treatment of pulmonary infections in CF patients. Although the clinical data concerning this specific population are relatively scarce, the beginning of the first large randomized study evaluating bacteriophage-based therapy in burn infections suggests that the time has come to assess the effectiveness of this new therapy in CF P. aeruginosa pneumonia. Consequently, the aim of this review is, after a brief history, to summarize the evidence concerning bacteriophage efficacy against P. aeruginosa and, more specifically, the in vitro studies, animal models, and clinical trials targeting CF.

  19. Community-based interference against integration of Pseudomonas aeruginosa into human salivary microbial biofilm.

    PubMed

    He, X; Hu, W; He, J; Guo, L; Lux, R; Shi, W

    2011-12-01

    As part of the human gastrointestinal tract, the oral cavity represents a complex biological system and harbors diverse bacterial species. Unlike the gut microbiota, which is often considered a health asset, studies of the oral commensal microbiota have been largely limited to their implication in oral conditions such as dental caries and periodontal disease. Less emphasis has been given to their potential beneficial roles, especially the protective effects against oral colonization by foreign or pathogenic bacteria. In this study, we used salivary microbiota derived from healthy human subjects to investigate protective effects against colonization and integration of Pseudomonas aeruginosa, an opportunistic bacterial pathogen, into developing or pre-formed salivary biofilms. When co-cultivated in saliva medium, P. aeruginosa persisted in the planktonic phase, but failed to integrate into the salivary microbial community during biofilm formation. Furthermore, in saliva medium supplemented with sucrose, the oral microbiota inhibited the growth of P. aeruginosa by producing lactic acid. More interestingly, while pre-formed salivary biofilms were able to prevent P. aeruginosa colonization, the same biofilms recovered from mild chlorhexidine gluconate treatment displayed a shift in microbial composition and showed a drastic reduction in protection. Our study indicates that normal oral communities with balanced microbial compositions could be important in effectively preventing the integration of foreign or pathogenic bacterial species, such as P. aeruginosa.

  20. Intranasal Immunization Strategy To Impede Pilin-Mediated Binding of Pseudomonas aeruginosa to Airway Epithelial Cells

    PubMed Central

    Hsieh, Jennifer C.; Tham, Doris M.; Feng, Weijun; Huang, Fan; Embaie, Selamawit; Liu, Keyi; Dean, Deborah; Hertle, Ralf; FitzGerald, David J.; Mrsny, Randall J.

    2005-01-01

    Prevention of pulmonary Pseudomonas aeruginosa infections represents a critical unmet medical need for cystic fibrosis (CF) patients. We have examined the tenet that a mucosal immunization approach can reduce interactions of a piliated form of this opportunistic pathogen with respiratory epithelial cells. Vaccinations were performed using ntPEpilinPAK, a protein chimera composed of a nontoxic form of P. aeruginosa exotoxin A (ntPE), where the C-terminal loop amino acid sequence of the PAK strain pilin protein was inserted in place of the ntPE Ib domain. Intranasal (i.n.) immunization of BALB/c mice with ntPEpilinPAK generated both serum and saliva immune responses. A series of in vitro studies showed that diluted samples of saliva obtained from immunized mice reduced pilin-dependent P. aeruginosa binding to polarized human tracheal epithelial cells, protected human pulmonary epithelial cells from cytotoxic actions associated with bacterial challenge, and reduced exotoxin A toxicity. Overall, i.n. administration of ntPEpilinPAK induced mucosal and systemic immune responses that may be beneficial for blocking early stage adhesion and/or infection events of epithelial cell-P. aeruginosa interactions at oropharyngeal surfaces. PMID:16239575

  1. Nanospecific Inhibition of Pyoverdine Siderophore Production in Pseudomonas Chlororaphis O6 by CuO Nanoparticles

    SciTech Connect

    Dimkpa, Christian O.; McLean, Joan E.; Britt, David W.; Johnson, William P.; Arey, Bruce W.; Lea, Alan S.; Anderson, Anne J.

    2012-03-01

    As traditional antibiotics become less effective against a growing number of pathogens, engineered nanoparticles (NPs) are becoming more widely applied as biocides. NPs of Ag, ZnO, and CuO exhibit dose-dependent antimicrobial activity; however, information is scant on the impact of sublethal levels of NPs on bacteria. In this paper, we evaluated the effect of a sublethal concentration (200 mg/L) of commercial CuO NPs on the expression of genes involved in the production of the fluorescent siderophore, pyoverdine (PVD) in the plant-beneficial bacterium Pseudomonas chlororaphis O6. PVDs are important in microbe-microbe and microbe-plant interactions, and are a virulence factor in pathogenic pseudomonads. Cells challenged with the NPs had reduced amounts of PVD in their periplasm and the external medium. The NPs impaired the expression of genes involved in transport of the PVD precursor through the plasmamembrane, PVD maturation in the periplasm, and export through the outer membrane. Also, expression from one of three predicted Fe-PVD receptors was reduced by the NPs. As these effects were not observed for cells challenged with copper ions, this is a nanoparticlespecific phenomenon mediating cellular reprogramming in bacteria, affecting secondary metabolism and thus associated critical microbial processes. The regulation of bacterial genes and secondary metabolites by sublethal doses of a common metal oxide NP has strong environmental and medical implications.

  2. Bacteriophage-based therapy in cystic fibrosis-associated Pseudomonas aeruginosa infections: rationale and current status

    PubMed Central

    Hraiech, Sami; Brégeon, Fabienne; Rolain, Jean-Marc

    2015-01-01

    Pulmonary infections involving Pseudomonas aeruginosa are among the leading causes of the deterioration of the respiratory status of cystic fibrosis (CF) patients. The emergence of multidrug-resistant strains in such populations, favored by iterative antibiotic cures, has led to the urgent need for new therapies. Among them, bacteriophage-based therapies deserve a focus. One century of empiric use in the ex-USSR countries suggests that bacteriophages may have beneficial effects against a large range of bacterial infections. Interest in bacteriophages has recently renewed in Western countries, and the in vitro data available suggest that bacteriophage-based therapy may be of significant interest for the treatment of pulmonary infections in CF patients. Although the clinical data concerning this specific population are relatively scarce, the beginning of the first large randomized study evaluating bacteriophage-based therapy in burn infections suggests that the time has come to assess the effectiveness of this new therapy in CF P. aeruginosa pneumonia. Consequently, the aim of this review is, after a brief history, to summarize the evidence concerning bacteriophage efficacy against P. aeruginosa and, more specifically, the in vitro studies, animal models, and clinical trials targeting CF. PMID:26213462

  3. Quantitative analysis of chemotaxis towards toluene by Pseudomonas putida in a convection-free microfluidic device.

    PubMed

    Wang, Xiaopu; Atencia, Javier; Ford, Roseanne M

    2015-05-01

    Chemotaxis has been shown to be beneficial for the migration of soil-inhabiting bacteria towards industrial chemical pollutants, which they degrade. Many studies have demonstrated the importance of this microbial property under various circumstances; however, few quantitative analyses have been undertaken to measure the two essential parameters that characterize the chemotaxis of bioremediation bacteria: the chemotactic sensitivity coefficient χ(0) and the chemotactic receptor constant K(c). The main challenge to determine these parameters is that χ(0) and K(c) are coupled together in non-linear mathematical models used to evaluate them. In this study we developed a method to accurately measure these parameters for Pseudomonas putida in the presence of toluene, an important pollutant in groundwater contamination. Our approach uses a multilayer microfluidic device to expose bacteria to a convection-free linear chemical gradient of toluene that is stable over time. The bacterial distribution within the gradient is measured in terms of fluorescence intensity, and is then used to fit the parameters Kc and χ(0) with mathematical models. Critically, bacterial distributions under chemical gradients at two different concentrations were used to solve for both parameters independently. To validate the approach, the chemotaxis parameters of Escherichia coli strains towards α-methylaspartate were experimentally derived and were found to be consistent with published results from related work.

  4. A competition model between Pseudomonas fluorescens and pathogens via iron chelation.

    PubMed

    Fgaier, Hedia; Eberl, Hermann J

    2010-04-21

    In this study we present a competition model between a non-chelator (e.g. pathogen) microorganism and an iron chelator microorganism (e.g. Pseudomonas fluorescens). This latter is a beneficial bacteria that can inhibit the growth of the non-chelator through its iron chelating capability. This phenomena of iron chelation is shown to prevent the pathogen from proliferating to numbers capable of causing disease. A mathematical model is formulated and used to study this competition. The model proposes a new and simple conceptual explanation of interactions. It is a nonlinear system of ordinary differential equations. A qualitative analysis of the model for the batch case (no inflow or outflow from the system) is carried out and the global behavior of the model variables is studied. For the chemostat case, the equilibrium points were derived and their stability was performed through extensive numerical simulations. It is found that iron chelation is able to control the non-chelator microorganism growth under a wide range of conditions. PMID:20005236

  5. Three small RNAs jointly ensure secondary metabolism and biocontrol in Pseudomonas fluorescens CHA0.

    PubMed

    Kay, Elisabeth; Dubuis, Christophe; Haas, Dieter

    2005-11-22

    In many Gram-negative bacteria, the GacS/GacA two-component system positively controls the expression of extracellular products or storage compounds. In the plant-beneficial rhizosphere bacterium Pseudomonas fluorescens CHA0, the GacS/GacA system is essential for the production of antibiotic compounds and hence for biological control of root-pathogenic fungi. The small (119-nt) RNA RsmX discovered in this study, together with RsmY and RsmZ, forms a triad of GacA-dependent small RNAs, which sequester the RNA-binding proteins RsmA and RsmE and thereby antagonize translational repression exerted by these proteins in strain CHA0. This small RNA triad was found to be both necessary and sufficient for posttranscriptional derepression of biocontrol factors and for protection of cucumber from Pythium ultimum. The same three small RNAs also positively regulated swarming motility and the synthesis of a quorum-sensing signal, which is unrelated to N-acyl-homoserine lactones, and which autoinduces the Gac/Rsm cascade. Expression of RsmX and RsmY increased in parallel throughout cell growth, whereas RsmZ was produced during the late growth phase. This differential expression is assumed to facilitate fine tuning of GacS/A-controlled cell population density-dependent regulation in P. fluorescens.

  6. Co-evolutionary dynamics between public good producers and cheats in the bacterium Pseudomonas aeruginosa.

    PubMed

    Kümmerli, R; Santorelli, L A; Granato, E T; Dumas, Z; Dobay, A; Griffin, A S; West, S A

    2015-12-01

    The production of beneficial public goods is common in the microbial world, and so is cheating--the exploitation of public goods by nonproducing mutants. Here, we examine co-evolutionary dynamics between cooperators and cheats and ask whether cooperators can evolve strategies to reduce the burden of exploitation, and whether cheats in turn can improve their exploitation abilities. We evolved cooperators of the bacterium Pseudomonas aeruginosa, producing the shareable iron-scavenging siderophore pyoverdine, together with cheats, defective in pyoverdine production but proficient in uptake. We found that cooperators managed to co-exist with cheats in 56% of all replicates over approximately 150 generations of experimental evolution. Growth and competition assays revealed that co-existence was fostered by a combination of general adaptions to the media and specific adaptions to the co-evolving opponent. Phenotypic screening and whole-genome resequencing of evolved clones confirmed this pattern, and suggest that cooperators became less exploitable by cheats because they significantly reduced their pyoverdine investment. Cheats, meanwhile, improved exploitation efficiency through mutations blocking the costly pyoverdine-signalling pathway. Moreover, cooperators and cheats evolved reduced motility, a pattern that likely represents adaptation to laboratory conditions, but at the same time also affects social interactions by reducing strain mixing and pyoverdine sharing. Overall, we observed parallel evolution, where co-existence of cooperators and cheats was enabled by a combination of adaptations to the abiotic and social environment and their interactions. PMID:26348785

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

    PubMed

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

    2000-11-01

    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 HKPA-induced production of tumor necrosis factor alpha (TNF), interleukin (IL-) 10, IL-6 and IL-8 (all P<0.05). P-ExA-induced inhibition of IL-10, IL-6 and IL-8 release was not dependent on reduced TNF concentrations, since the relative attenuation of the production of these cytokines was similar in the presence or absence of a neutralizing anti-TNF antibody. The effect of P-ExA on cytokine production may offer a disadvantage to the host with respect to clearance of the infection.

  8. Iron metabolism in Pseudomonas: salicylic acid, a siderophore of Pseudomonas fluorescens CHAO.

    PubMed

    Meyer, J M; Azelvandre, P; Georges, C

    1992-12-01

    Under iron-starvation conditions of growth, Pseudomonas fluorescens CHA0, a soil isolate involved in phytopathogenic fungi antagonisms, produced, together with pyoverdine, a second iron-chelating compound which was purified and identified by spectroscopy, HPLC and 1H-NMR to be salicylic acid. Mutants unable to synthesize pyoverdine overproduced this compound by a factor of 9-14. The biosynthesis of salicylic acid was under iron control; it was fully inhibited by 5 microM added iron in the growth medium. In contrast, salicylic acid of either bacterial or commercial origin facilitated labeled iron incorporation in iron-starved cells. Based on these two relationships observed with bacterial iron metabolism it is concluded that salicylic acid has a siderophore function for this strain. PMID:1292472

  9. Differential habitat use and niche partitioning by Pseudomonas species in human homes.

    PubMed

    Remold, Susanna K; Brown, Christopher K; Farris, Justin E; Hundley, Thomas C; Perpich, Jessica A; Purdy, Megan E

    2011-10-01

    Many species of Pseudomonas have the ability to use a variety of resources and habitats, and as a result Pseudomonas are often characterized as having broad fundamental niches. We questioned whether actual habitat use by Pseudomonas species is equally broad. To do this, we sampled extensively to describe the biogeography of Pseudomonas within the human home, which presents a wide variety of habitats for microbes that live in close proximity to humans but are not part of the human flora, and for microbes that are opportunistic pathogens, such as Pseudomonas aeruginosa. From 960 samples taken in 20 homes, we obtained 163 Pseudomonas isolates. The most prevalent based on identification using the SepsiTest BLAST analysis of 16S rRNA (http://www.sepsitest-blast.de) were Pseudomonas monteilii (42 isolates), Pseudomonas plecoglossicida, Pseudomonas fulva, and P. aeruginosa (approximately 25 each). Of these, all but P. fulva differed in recovery rates among evaluated habitat types (drains, soils, water, internal vertebrate sites, vertebrate skin, inanimate surfaces, and garbage/compost) and all four species also differed in recovery rates among subcategories of habitat types (e.g., types of soils or drains). We also found that at both levels of habitat resolution, each of these six most common species (the four above plus Pseudomonas putida and Pseudomonas oryzihabitans) were over- or under-represented in some habitats relative to their contributions to the total Pseudomonas collected across all habitats. This pattern is consistent with niche partitioning. These results suggest that, whereas Pseudomonas are often characterized as generalists with broad fundamental niches, these species in fact have more restricted realized niches. Furthermore, niche partitioning driven by competition among Pseudomonas species may be contributing to the observed variability in habitat use by Pseudomonas in this system.

  10. Differential habitat use and niche partitioning by Pseudomonas species in human homes.

    PubMed

    Remold, Susanna K; Brown, Christopher K; Farris, Justin E; Hundley, Thomas C; Perpich, Jessica A; Purdy, Megan E

    2011-10-01

    Many species of Pseudomonas have the ability to use a variety of resources and habitats, and as a result Pseudomonas are often characterized as having broad fundamental niches. We questioned whether actual habitat use by Pseudomonas species is equally broad. To do this, we sampled extensively to describe the biogeography of Pseudomonas within the human home, which presents a wide variety of habitats for microbes that live in close proximity to humans but are not part of the human flora, and for microbes that are opportunistic pathogens, such as Pseudomonas aeruginosa. From 960 samples taken in 20 homes, we obtained 163 Pseudomonas isolates. The most prevalent based on identification using the SepsiTest BLAST analysis of 16S rRNA (http://www.sepsitest-blast.de) were Pseudomonas monteilii (42 isolates), Pseudomonas plecoglossicida, Pseudomonas fulva, and P. aeruginosa (approximately 25 each). Of these, all but P. fulva differed in recovery rates among evaluated habitat types (drains, soils, water, internal vertebrate sites, vertebrate skin, inanimate surfaces, and garbage/compost) and all four species also differed in recovery rates among subcategories of habitat types (e.g., types of soils or drains). We also found that at both levels of habitat resolution, each of these six most common species (the four above plus Pseudomonas putida and Pseudomonas oryzihabitans) were over- or under-represented in some habitats relative to their contributions to the total Pseudomonas collected across all habitats. This pattern is consistent with niche partitioning. These results suggest that, whereas Pseudomonas are often characterized as generalists with broad fundamental niches, these species in fact have more restricted realized niches. Furthermore, niche partitioning driven by competition among Pseudomonas species may be contributing to the observed variability in habitat use by Pseudomonas in this system. PMID:21503776

  11. Dictyostelium discoideum as a surrogate host-microbe model for antivirulence screening in Pseudomonas aeruginosa PAO1.

    PubMed

    Bravo-Toncio, Catalina; Álvarez, Javiera A; Campos, Francisca; Ortíz-Severín, Javiera; Varas, Macarena; Cabrera, Ricardo; Lagos, Carlos F; Chávez, Francisco P

    2016-05-01

    The interest of the pharmaceutical industry in developing new antibiotics is decreasing, as established screening systems which identify compounds that kill or inhibit the growth of bacteria can no longer be used. Consequently, antimicrobial screening using classical minimum inhibitory concentration (MIC) measurements is becoming obsolete. The discovery of antimicrobial agents that specifically target a bacterial pathogen without affecting the host and its beneficial bacteria is a promising strategy. However, few host-microbe models are available for in vivo screening of novel antivirulence molecules. Here we designed high-throughput developmental assays in the social amoeba Dictyostelium discoideum to measure Pseudomonas aeruginosa virulence and to screen for novel antivirulence molecules without side effects to the host and its beneficial bacteria Klebsiella aerogenes. Thirty compounds were evaluated that had been previously selected by virtual screening for inhibitors of P. aeruginosa PAO1 polyphosphate kinase 1 (PaPPK1) and diverse compounds with combined PPK1 inhibitory and antivirulence activities were identified. This approach demonstrates that D. discoideum is a suitable surrogate host for preliminary high-throughput screening of antivirulence agents and that PPK1 is a suitable target for developing novel antivirulence compounds that can be further validated in mammalian models. PMID:27066943

  12. Dictyostelium discoideum as a surrogate host-microbe model for antivirulence screening in Pseudomonas aeruginosa PAO1.

    PubMed

    Bravo-Toncio, Catalina; Álvarez, Javiera A; Campos, Francisca; Ortíz-Severín, Javiera; Varas, Macarena; Cabrera, Ricardo; Lagos, Carlos F; Chávez, Francisco P

    2016-05-01

    The interest of the pharmaceutical industry in developing new antibiotics is decreasing, as established screening systems which identify compounds that kill or inhibit the growth of bacteria can no longer be used. Consequently, antimicrobial screening using classical minimum inhibitory concentration (MIC) measurements is becoming obsolete. The discovery of antimicrobial agents that specifically target a bacterial pathogen without affecting the host and its beneficial bacteria is a promising strategy. However, few host-microbe models are available for in vivo screening of novel antivirulence molecules. Here we designed high-throughput developmental assays in the social amoeba Dictyostelium discoideum to measure Pseudomonas aeruginosa virulence and to screen for novel antivirulence molecules without side effects to the host and its beneficial bacteria Klebsiella aerogenes. Thirty compounds were evaluated that had been previously selected by virtual screening for inhibitors of P. aeruginosa PAO1 polyphosphate kinase 1 (PaPPK1) and diverse compounds with combined PPK1 inhibitory and antivirulence activities were identified. This approach demonstrates that D. discoideum is a suitable surrogate host for preliminary high-throughput screening of antivirulence agents and that PPK1 is a suitable target for developing novel antivirulence compounds that can be further validated in mammalian models.

  13. Role of secondary metabolites in the interaction between Pseudomonas fluorescens and soil microorganisms under iron-limited conditions.

    PubMed

    Deveau, Aurélie; Gross, Harald; Palin, Béatrice; Mehnaz, Samina; Schnepf, Max; Leblond, Pierre; Dorrestein, Pieter C; Aigle, Bertrand

    2016-08-01

    Microorganisms can be versatile in their interactions with each other, being variously beneficial, neutral or antagonistic in their effect. Although this versatility has been observed among many microorganisms and in many environments, little is known regarding the mechanisms leading to these changes in behavior. In the present work, we analyzed the mechanism by which the soil bacterium Pseudomonas fluorescens BBc6R8 shifts from stimulating the growth of the ectomycorrhizal fungus Laccaria bicolor S238N to killing the fungus. We show that among the three secondary metabolites produced by the bacterial strain-the siderophores enantio-pyochelin and pyoverdine, and the biosurfactant viscosin-the siderophores are mainly responsible for the antagonistic activity of the bacterium under iron-limited conditions. While the bacterial strain continues to produce beneficial factors, their effects are overridden by the action of their siderophores. This antagonistic activity of the strain P. fluorescens BBC6R8 in iron-depleted environments is not restricted to its influence on L. bicolor, since it was also seen to inhibit the growth of the actinomycete Streptomyces ambofaciens ATCC23877. We show that the strain P. fluorescens BBc6R8 uses different strategies to acquire iron, depending on certain biotic and abiotic factors. PMID:27199346

  14. Soil Pseudomonas community structure and its antagonism towards Rhizoctonia solani under the stress of acetochlor.

    PubMed

    Wu, Minna; Zhang, Xiaoli; Zhang, Huiwen; Zhang, Yan; Li, Xinyu; Zhou, Qixing; Zhang, Chenggang

    2009-09-01

    In a microcosm experiment, the amplified ribosomal DNA restriction analysis was adopted to investigate the Pseudomonas community structure in soils applied with different concentrations (0, 50, 150, and 250 mg/kg) of acetochlor, and an in vitro assay was made to examine the antagonistic activity of isolated Pseudomonas strains acting on soil-borne pathogen Rhizoctonia solani. The results showed that acetochlor application changed the community structure of Pseudomonas in aquic brown soil. The diversity of Pseudomonas and the amount of isolated Pseudomonas strains with antagonistic activity decreased with an increasing acetochlor concentration, and the toxic effect of acetochlor reached to a steady level at 150-250 mg/kg.

  15. Draft Genome Sequence of Pseudomonas fluorescens LMG 5329, a White Line-Inducing Principle-Producing Bioindicator for the Mushroom Pathogen Pseudomonas tolaasii

    PubMed Central

    Rokni-Zadeh, Hassan; Zarrineh, Peyman

    2013-01-01

    Pseudomonas tolaasii, the causative agent of Agaricus bisporus brown blotch disease, can be identified by the white line reaction, occurring upon confrontation of the tolaasin-producing mushroom pathogen with “Pseudomonas reactans,” producing the lipopeptide white line-inducing principle (WLIP). The draft genome sequence of the WLIP-producing indicator Pseudomonas fluorescens strain LMG 5329 is reported here. PMID:23887909

  16. Two unusual pilin sequences from different isolates of Pseudomonas aeruginosa.

    PubMed Central

    Pasloske, B L; Sastry, P A; Finlay, B B; Paranchych, W

    1988-01-01

    The pilin genes of two Pseudomonas aeruginosa strains isolated from two different patients with cystic fibrosis were cloned and sequenced. The predicted protein sequences of these two pilins had several unusual features compared with other published P. aeruginosa pilin sequences. PMID:2841299

  17. Functional bacterial amyloid increases Pseudomonas biofilm hydrophobicity and stiffness.

    PubMed

    Zeng, Guanghong; Vad, Brian S; Dueholm, Morten S; Christiansen, Gunna; Nilsson, Martin; Tolker-Nielsen, Tim; Nielsen, Per H; Meyer, Rikke L; Otzen, Daniel E

    2015-01-01

    The success of Pseudomonas species as opportunistic pathogens derives in great part from their ability to form stable biofilms that offer protection against chemical and mechanical attack. The extracellular matrix of biofilms contains numerous biomolecules, and it has recently been discovered that in Pseudomonas one of the components includes β-sheet rich amyloid fibrils (functional amyloid) produced by the fap operon. However, the role of the functional amyloid within the biofilm has not yet been investigated in detail. Here we investigate how the fap-based amyloid produced by Pseudomonas affects biofilm 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 stiffness 20-fold. Deletion of any one of the individual members of in the fap operon (except the putative chaperone FapA) abolishes this ability to increase biofilm stiffness and correlates with the loss of amyloid. We conclude that amyloid makes major contributions to biofilm mechanical robustness.

  18. Pseudomonas arthritis treated with parenteral and intra-articular ceftazidime.

    PubMed Central

    Walton, K; Hilton, R C; Sen, R A

    1985-01-01

    A 73-year-old diabetic presented with septic arthritis of the knee; Pseudomonas aeruginosa was isolated. She was successfully treated with a combination of parenteral and intra-articular ceftazidime, after failure to eradicate the organism with adequate serum levels of gentamicin and full doses of azlocillin. PMID:3896166

  19. Functional bacterial amyloid increases Pseudomonas biofilm hydrophobicity and stiffness

    PubMed Central

    Zeng, Guanghong; Vad, Brian S.; Dueholm, Morten S.; Christiansen, Gunna; Nilsson, Martin; Tolker-Nielsen, Tim; Nielsen, Per H.; Meyer, Rikke L.; Otzen, Daniel E.

    2015-01-01

    The success of Pseudomonas species as opportunistic pathogens derives in great part from their ability to form stable biofilms that offer protection against chemical and mechanical attack. The extracellular matrix of biofilms contains numerous biomolecules, and it has recently been discovered that in Pseudomonas one of the components includes β-sheet rich amyloid fibrils (functional amyloid) produced by the fap operon. However, the role of the functional amyloid within the biofilm has not yet been investigated in detail. Here we investigate how the fap-based amyloid produced by Pseudomonas affects biofilm 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 stiffness 20-fold. Deletion of any one of the individual members of in the fap operon (except the putative chaperone FapA) abolishes this ability to increase biofilm stiffness and correlates with the loss of amyloid. We conclude that amyloid makes major contributions to biofilm mechanical robustness. PMID:26500638

  20. Chemotaxis to furan compounds by furan-degrading Pseudomonas strains

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Two Pseudomonas strains known to utilize furan derivatives were shown to be attracted to furfural, 5-hydroxymethylfurfural, furfuryl alcohol, and 2-furoic acid in the absence of furan metabolism. In addition, a LysR-family regulatory protein known to regulate furan metabolic genes was found to be i...

  1. Pseudomonas seleniipraecipitans proteins potentially involved in selenite reduction

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pseudomonas seleniipraecipitans grows in the presence of high levels of selenite and selenate and reduces both oxyanions to elemental selenium, a property that may make P. seleniipraecipitans useful as an inoculant for biobarriers designed to remove selenite or selenate from ground or surface-waters...

  2. Frequency of Antibiotic-Producing Pseudomonas spp. in Natural Environments

    PubMed Central

    Raaijmakers, J. M.; Weller, D. M.; Thomashow, L. S.

    1997-01-01

    The antibiotics phenazine-1-carboxylic acid (PCA) and 2,4-diacetylphloroglucinol (Phl) are major determinants of biological control of soilborne plant pathogens by various strains of fluorescent Pseudomonas spp. In this study, we described primers and probes that enable specific and efficient detection of a wide variety of fluorescent Pseudomonas strains that produce various phenazine antibiotics or Phl. PCR analysis and Southern hybridization demonstrated that specific genes within the biosynthetic loci for Phl and PCA are conserved among various Pseudomonas strains of worldwide origin. The frequency of Phl- and PCA-producing fluorescent pseudomonads was determined on roots of wheat grown in three soils suppressive to take-all disease of wheat and four soils conducive to take-all by colony hybridization followed by PCR. Phenazine-producing strains were not detected on roots from any of the soils. However, Phl-producing fluorescent pseudomonads were isolated from all three take-all-suppressive soils at densities ranging from approximately 5 x 10(sup5) to 2 x 10(sup6) CFU per g of root. In the complementary conducive soils, Phl-producing pseudomonads were not detected or were detected at densities at least 40-fold lower than those in the suppressive soils. We speculate that fluorescent Pseudomonas spp. that produce Phl play an important role in the natural suppressiveness of these soils to take-all disease of wheat. PMID:16535555

  3. Engineering the Soil Bacterium Pseudomonas putida for Arsenic Methylation

    PubMed Central

    Chen, Jian; Qin, Jie; Zhu, Yong-Guan; de Lorenzo, Víctor

    2013-01-01

    Accumulation of arsenic has potential health risks through consumption of food. Here, we inserted the arsenite [As(III)] S-adenosylmethionine methyltransferase (ArsM) gene into the chromosome of Pseudomonas putida KT2440. Recombinant bacteria methylate inorganic arsenic into less toxic organoarsenicals. This has the potential for bioremediation of environmental arsenic and reducing arsenic contamination in food. PMID:23645194

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

    PubMed Central

    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. PMID:11329471

  5. 21 CFR 866.3415 - Pseudomonas spp. serological reagents.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Pseudomonas spp. serological reagents. 866.3415 Section 866.3415 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3415...

  6. 21 CFR 866.3415 - Pseudomonas spp. serological reagents.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Pseudomonas spp. serological reagents. 866.3415 Section 866.3415 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3415...

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

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Pseudomonas spp. serological reagents. 866.3415 Section 866.3415 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3415...

  8. 21 CFR 866.3415 - Pseudomonas spp. serological reagents.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Pseudomonas spp. serological reagents. 866.3415 Section 866.3415 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3415...

  9. 21 CFR 866.3415 - Pseudomonas spp. serological reagents.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Pseudomonas spp. serological reagents. 866.3415 Section 866.3415 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3415...

  10. Draft Genome Sequence of Rice Isolate Pseudomonas chlororaphis EA105

    PubMed Central

    McCully, Lucy M.; Bitzer, Adam S.; Spence, Carla A.; Bais, Harsh P.

    2014-01-01

    Pseudomonas chlororaphis EA105, a strain isolated from rice rhizosphere, has shown antagonistic activities against a rice fungal pathogen, and could be important in defense against rice blast. We report the draft genome sequence of EA105, which is an estimated size of 6.6 Mb. PMID:25540352

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

    PubMed Central

    Andrade-Domínguez, Andrés

    2016-01-01

    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. PMID:27563032

  12. Antimicrobial properties of Pseudomonas strains producing the antibiotic mupirocin.

    PubMed

    Matthijs, Sandra; Vander Wauven, Corinne; Cornu, Bertrand; Ye, Lumeng; Cornelis, Pierre; Thomas, Christopher M; Ongena, Marc

    2014-10-01

    Mupirocin is a polyketide antibiotic with broad antibacterial activity. It was isolated and characterized about 40 years ago from Pseudomonas fluorescens NCIMB 10586. To study the phylogenetic distribution of mupirocin producing strains in the genus Pseudomonas a large collection of Pseudomonas strains of worldwide origin, consisting of 117 Pseudomonas type strains and 461 strains isolated from different biological origins, was screened by PCR for the mmpD gene of the mupirocin gene cluster. Five mmpD(+) strains from different geographic and biological origin were identified. They all produced mupirocin and were strongly antagonistic against Staphylococcus aureus. Phylogenetic analysis showed that mupirocin production is limited to a single species. Inactivation of mupirocin production leads to complete loss of in vitro antagonism against S. aureus, except on certain iron-reduced media where the siderophore pyoverdine is responsible for the in vitro antagonism of a mupirocin-negative mutant. In addition to mupirocin some of the strains produced lipopeptides of the massetolide group. These lipopeptides do not play a role in the observed in vitro antagonism of the mupirocin producing strains against S. aureus. PMID:25303834

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

    PubMed

    Andrade-Domínguez, Andrés; Kolter, Roberto

    2016-01-01

    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. PMID:27563032

  14. Complete Genome Sequence of Pseudomonas balearica DSM 6083T

    PubMed Central

    Salvà-Serra, Francisco; Jaén-Luchoro, Daniel; Seguí, Carolina; Aliaga, Francisco; Busquets, Antonio; Gomila, Margarita; Lalucat, Jorge

    2016-01-01

    The whole-genome sequence of Pseudomonas balearica SP1402 (DSM 6083T) has been completed and annotated. It was isolated as a naphthalene degrader from water of a lagooning wastewater treatment plant. P. balearica strains tolerate up to 8.5% NaCl and are considered true marine denitrifiers. PMID:27103708

  15. Pseudomonas prosekii sp. nov., a novel psychrotrophic bacterium from Antarctica.

    PubMed

    Kosina, Marcel; Barták, Miloš; Mašlaňová, Ivana; Pascutti, Andrea Vávrová; Sedo, Ondrej; Lexa, Matej; Sedláček, Ivo

    2013-12-01

    During Czech expeditions at James Ross Island, Antarctica, in the years 2007-2009, the bacterial diversity of the genus Pseudomonas was studied. Twelve fluorescent Pseudomonas strains were isolated from various samples and were subjected to a detailed taxonomic study. A polyphasic approach included genotypic and phenotypic analyses. The genotypic analysis involved sequencing of rrs, rpoB and rpoD genes, DNA-DNA hybridization (DDH) studies as well as manual ribotyping using HindIII endonuclease. The phenotypic characterization included conventional tests as well as biotyping using the Biolog system, protein profiling by SDS-PAGE, and MALDI-TOF MS analysis. Our taxonomic study revealed that all isolates belonged to the same Pseudomonas species with psychrotrophic growth not exceeding 37 °C. The cultures showed a unique position among the phylogenetically related pseudomonads. DDH experiment between the proposed type strain of the antarctic isolates and the closest neighbour P. arsenicoxydans CCM 8423(T) showed only 40.9-50.1 % similarity, thus confirming that the characterized strains do not belong to the P. arsenicoxydans species. According to the results obtained we propose the name P. prosekii sp. nov. for this novel Pseudomonas taxon with type strain AN/28/1(T) (=CCM 7990(T) and LMG 26867(T)). PMID:23794042

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

    PubMed Central

    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

  17. 40 CFR 435.50 - Applicability; description of the beneficial use subcategory.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... continental United States and west of the 98th meridian for which the produced water has a use in agriculture... Agricultural and Wildlife Water Use Subcategory § 435.50 Applicability; description of the beneficial...

  18. 40 CFR 435.50 - Applicability; description of the beneficial use subcategory.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... States and west of the 98th meridian for which the produced water has a use in agriculture or wildlife... Wildlife Water Use Subcategory § 435.50 Applicability; description of the beneficial use subcategory....

  19. A comparative analysis of metal transportomes from metabolically versatile Pseudomonas

    PubMed Central

    Haritha, Adhikarla; Rodrigue, Agnes; Mohan, Pamarthi Maruthi

    2008-01-01

    Background The availability of complete genome sequences of versatile Pseudomonas occupying remarkably diverse ecological niches enabled to gain insights into their adaptative assets. The objective of this study was to analyze the complete genetic repertoires of metal transporters (metal transportomes) from four representative Pseudomonas species and to identify metal transporters with "Genomic Island" associated features. Methods A comparative metal transporter inventory was built for the following four Pseudomonas species: P.putida (Ppu) KT2440, P.aeruginosa (Pae) PA01, P.fluorescens (Pfl) Pf-5 and P.syringae (Psy)pv.tomato DC3000 using TIGR-CMR and Transport DB. Genomic analysis of essential and toxic metal ion transporters was accomplished from the above inventory. Metal transporters with "Genomic Island" associated features were identified using Islandpath analysis. Results Dataset cataloguing has been executed for 262 metal transporters from the four spp. Additional metal ion transporters belonging to NiCoT, Ca P-type ATPase, Cu P-type ATPases, ZIP and MgtC families were identified. In Psy DC3000, 48% of metal transporters showed strong GI features while it was 45% in Ppu KT2440. In Pfl Pf-5 and Pae PA01 only 26% of their metal transporters exhibited GI features. Conclusion Our comparative inventory of 262 metal transporters from four versatile Pseudomonas spp is the complete suite of metal transportomes analysed till date in a prokaryotic genus. This study identified differences in the basic composition of metal transportomes from Pseudomonas occupying diverse ecological niches and also elucidated their novel features. Based on this inventory we analysed the role of horizontal gene transfer in expansion and variability of metal transporter families. PMID:18816395

  20. Beneficial Effects of Probiotic and Food Borne Yeasts on Human Health

    PubMed Central

    Moslehi-Jenabian, Saloomeh; Pedersen, Line Lindegaard; Jespersen, Lene

    2010-01-01

    Besides being important in the fermentation of foods and beverages, yeasts have shown numerous beneficial effects on human health. Among these, probiotic effects are the most well known health effects including prevention and treatment of intestinal diseases and immunomodulatory effects. Other beneficial functions of yeasts are improvement of bioavailability of minerals through the hydrolysis of phytate, folate biofortification and detoxification of mycotoxins due to surface binding to the yeast cell wall. PMID:22254033

  1. Experimental Evolution as an Underutilized Tool for Studying Beneficial Animal-Microbe Interactions.

    PubMed

    Hoang, Kim L; Morran, Levi T; Gerardo, Nicole M

    2016-01-01

    Microorganisms play a significant role in the evolution and functioning of the eukaryotes with which they interact. Much of our understanding of beneficial host-microbe interactions stems from studying already established associations; we often infer the genotypic and environmental conditions that led to the existing host-microbe relationships. However, several outstanding questions remain, including understanding how host and microbial (internal) traits, and ecological and evolutionary (external) processes, influence the origin of beneficial host-microbe associations. Experimental evolution has helped address a range of evolutionary and ecological questions across different model systems; however, it has been greatly underutilized as a tool to study beneficial host-microbe associations. In this review, we suggest ways in which experimental evolution can further our understanding of the proximate and ultimate mechanisms shaping mutualistic interactions between eukaryotic hosts and microbes. By tracking beneficial interactions under defined conditions or evolving novel associations among hosts and microbes with little prior evolutionary interaction, we can link specific genotypes to phenotypes that can be directly measured. Moreover, this approach will help address existing puzzles in beneficial symbiosis research: how symbioses evolve, how symbioses are maintained, and how both host and microbe influence their partner's evolutionary trajectories. By bridging theoretical predictions and empirical tests, experimental evolution provides us with another approach to test hypotheses regarding the evolution of beneficial host-microbe associations. PMID:27679620

  2. Beneficial insects attracted to native flowering buckwheats (Eriogonum Michx) in central Washington.

    PubMed

    James, David G; Seymour, Lorraine; Lauby, Gerry; Buckley, Katie

    2014-08-01

    Native plant and beneficial insect associations are relatively unstudied yet are important in native habitat restoration programs aimed at improving conservation biological control in perennial crops such as wine grapes. Beneficial insects (predators, parasitoids, pollinators) attracted to 10 species of flowering native wild buckwheat (Eriogonum spp.) in central Washington were identified and counted on transparent sticky traps. Combining all categories of beneficial insects, the mean number per trap ranged from 48.5 (Eriogonum umbellatum) to 167.7 (Eriogonum elatum). Three Eriogonum spp. (E. elatum, Eriogonum compositum, and Eriogonum niveum) attracted significantly more beneficial insects than the lowest-ranked species. E. niveum attracted greatest numbers of bees and parasitic wasps, and E. elatum was highly attractive to predatory true bugs and beneficial flies. Blooming periods of Eriogonum spp. extended from mid April to the end of September. This study demonstrates the attraction of beneficial insects to native flowering buckwheats and suggests their potential as a component of habitat restoration strategies to improve and sustain conservation biological control in Washington viticulture. PMID:24960157

  3. Experimental Evolution as an Underutilized Tool for Studying Beneficial Animal–Microbe Interactions

    PubMed Central

    Hoang, Kim L.; Morran, Levi T.; Gerardo, Nicole M.

    2016-01-01

    Microorganisms play a significant role in the evolution and functioning of the eukaryotes with which they interact. Much of our understanding of beneficial host–microbe interactions stems from studying already established associations; we often infer the genotypic and environmental conditions that led to the existing host–microbe relationships. However, several outstanding questions remain, including understanding how host and microbial (internal) traits, and ecological and evolutionary (external) processes, influence the origin of beneficial host–microbe associations. Experimental evolution has helped address a range of evolutionary and ecological questions across different model systems; however, it has been greatly underutilized as a tool to study beneficial host–microbe associations. In this review, we suggest ways in which experimental evolution can further our understanding of the proximate and ultimate mechanisms shaping mutualistic interactions between eukaryotic hosts and microbes. By tracking beneficial interactions under defined conditions or evolving novel associations among hosts and microbes with little prior evolutionary interaction, we can link specific genotypes to phenotypes that can be directly measured. Moreover, this approach will help address existing puzzles in beneficial symbiosis research: how symbioses evolve, how symbioses are maintained, and how both host and microbe influence their partner’s evolutionary trajectories. By bridging theoretical predictions and empirical tests, experimental evolution provides us with another approach to test hypotheses regarding the evolution of beneficial host–microbe associations. PMID:27679620

  4. Beneficial Insect Attraction to Milkweeds (Asclepias speciosa, Asclepias fascicularis) in Washington State, USA.

    PubMed

    James, David G; Seymour, Lorraine; Lauby, Gerry; Buckley, Katie

    2016-06-29

    Native plant and beneficial insect associations are relatively unstudied yet are important in native habitat restoration programs for improving and sustaining conservation biological control of arthropod pests in agricultural crops. Milkweeds (Asclepias spp.) are currently the focus of restoration programs in the USA aimed at reversing a decline in populations of the milkweed-dependent monarch butterfly (Danaus plexippus); however, little is known of the benefits of these plants to other beneficial insects. Beneficial insects (predators, parasitoids, pollinators) attracted to two milkweed species (Asclepias speciosa, Asclepias fascicularis) in central Washington State, WA, USA were identified and counted on transparent sticky traps attached to blooms over five seasons. Combining all categories of beneficial insects, means of 128 and 126 insects per trap were recorded for A. speciosa and A. fascicularis, respectively. Predatory and parasitic flies dominated trap catches for A. speciosa while parasitic wasps were the most commonly trapped beneficial insects on A. fascicularis. Bees were trapped commonly on both species, especially A. speciosa with native bees trapped in significantly greater numbers than honey bees. Beneficial insect attraction to A. speciosa and A. fascicularis was substantial. Therefore, these plants are ideal candidates for habitat restoration, intended to enhance conservation biological control, and for pollinator conservation. In central Washington, milkweed restoration programs for enhancement of D. plexippus populations should also provide benefits for pest suppression and pollinator conservation.

  5. Experimental Evolution as an Underutilized Tool for Studying Beneficial Animal-Microbe Interactions.

    PubMed

    Hoang, Kim L; Morran, Levi T; Gerardo, Nicole M

    2016-01-01

    Microorganisms play a significant role in the evolution and functioning of the eukaryotes with which they interact. Much of our understanding of beneficial host-microbe interactions stems from studying already established associations; we often infer the genotypic and environmental conditions that led to the existing host-microbe relationships. However, several outstanding questions remain, including understanding how host and microbial (internal) traits, and ecological and evolutionary (external) processes, influence the origin of beneficial host-microbe associations. Experimental evolution has helped address a range of evolutionary and ecological questions across different model systems; however, it has been greatly underutilized as a tool to study beneficial host-microbe associations. In this review, we suggest ways in which experimental evolution can further our understanding of the proximate and ultimate mechanisms shaping mutualistic interactions between eukaryotic hosts and microbes. By tracking beneficial interactions under defined conditions or evolving novel associations among hosts and microbes with little prior evolutionary interaction, we can link specific genotypes to phenotypes that can be directly measured. Moreover, this approach will help address existing puzzles in beneficial symbiosis research: how symbioses evolve, how symbioses are maintained, and how both host and microbe influence their partner's evolutionary trajectories. By bridging theoretical predictions and empirical tests, experimental evolution provides us with another approach to test hypotheses regarding the evolution of beneficial host-microbe associations.

  6. Beneficial Insect Attraction to Milkweeds (Asclepias speciosa, Asclepias fascicularis) in Washington State, USA

    PubMed Central

    James, David G.; Seymour, Lorraine; Lauby, Gerry; Buckley, Katie

    2016-01-01

    Native plant and beneficial insect associations are relatively unstudied yet are important in native habitat restoration programs for improving and sustaining conservation biological control of arthropod pests in agricultural crops. Milkweeds (Asclepias spp.) are currently the focus of restoration programs in the USA aimed at reversing a decline in populations of the milkweed-dependent monarch butterfly (Danaus plexippus); however, little is known of the benefits of these plants to other beneficial insects. Beneficial insects (predators, parasitoids, pollinators) attracted to two milkweed species (Asclepias speciosa, Asclepias fascicularis) in central Washington State, WA, USA were identified and counted on transparent sticky traps attached to blooms over five seasons. Combining all categories of beneficial insects, means of 128 and 126 insects per trap were recorded for A. speciosa and A. fascicularis, respectively. Predatory and parasitic flies dominated trap catches for A. speciosa while parasitic wasps were the most commonly trapped beneficial insects on A. fascicularis. Bees were trapped commonly on both species, especially A. speciosa with native bees trapped in significantly greater numbers than honey bees. Beneficial insect attraction to A. speciosa and A. fascicularis was substantial. Therefore, these plants are ideal candidates for habitat restoration, intended to enhance conservation biological control, and for pollinator conservation. In central Washington, milkweed restoration programs for enhancement of D. plexippus populations should also provide benefits for pest suppression and pollinator conservation. PMID:27367733

  7. Beneficial Insect Attraction to Milkweeds (Asclepias speciosa, Asclepias fascicularis) in Washington State, USA.

    PubMed

    James, David G; Seymour, Lorraine; Lauby, Gerry; Buckley, Katie

    2016-01-01

    Native plant and beneficial insect associations are relatively unstudied yet are important in native habitat restoration programs for improving and sustaining conservation biological control of arthropod pests in agricultural crops. Milkweeds (Asclepias spp.) are currently the focus of restoration programs in the USA aimed at reversing a decline in populations of the milkweed-dependent monarch butterfly (Danaus plexippus); however, little is known of the benefits of these plants to other beneficial insects. Beneficial insects (predators, parasitoids, pollinators) attracted to two milkweed species (Asclepias speciosa, Asclepias fascicularis) in central Washington State, WA, USA were identified and counted on transparent sticky traps attached to blooms over five seasons. Combining all categories of beneficial insects, means of 128 and 126 insects per trap were recorded for A. speciosa and A. fascicularis, respectively. Predatory and parasitic flies dominated trap catches for A. speciosa while parasitic wasps were the most commonly trapped beneficial insects on A. fascicularis. Bees were trapped commonly on both species, especially A. speciosa with native bees trapped in significantly greater numbers than honey bees. Beneficial insect attraction to A. speciosa and A. fascicularis was substantial. Therefore, these plants are ideal candidates for habitat restoration, intended to enhance conservation biological control, and for pollinator conservation. In central Washington, milkweed restoration programs for enhancement of D. plexippus populations should also provide benefits for pest suppression and pollinator conservation. PMID:27367733

  8. Beneficial insects attracted to native flowering buckwheats (Eriogonum Michx) in central Washington.

    PubMed

    James, David G; Seymour, Lorraine; Lauby, Gerry; Buckley, Katie

    2014-08-01

    Native plant and beneficial insect associations are relatively unstudied yet are important in native habitat restoration programs aimed at improving conservation biological control in perennial crops such as wine grapes. Beneficial insects (predators, parasitoids, pollinators) attracted to 10 species of flowering native wild buckwheat (Eriogonum spp.) in central Washington were identified and counted on transparent sticky traps. Combining all categories of beneficial insects, the mean number per trap ranged from 48.5 (Eriogonum umbellatum) to 167.7 (Eriogonum elatum). Three Eriogonum spp. (E. elatum, Eriogonum compositum, and Eriogonum niveum) attracted significantly more beneficial insects than the lowest-ranked species. E. niveum attracted greatest numbers of bees and parasitic wasps, and E. elatum was highly attractive to predatory true bugs and beneficial flies. Blooming periods of Eriogonum spp. extended from mid April to the end of September. This study demonstrates the attraction of beneficial insects to native flowering buckwheats and suggests their potential as a component of habitat restoration strategies to improve and sustain conservation biological control in Washington viticulture.

  9. Experimental Evolution as an Underutilized Tool for Studying Beneficial Animal–Microbe Interactions

    PubMed Central

    Hoang, Kim L.; Morran, Levi T.; Gerardo, Nicole M.

    2016-01-01

    Microorganisms play a significant role in the evolution and functioning of the eukaryotes with which they interact. Much of our understanding of beneficial host–microbe interactions stems from studying already established associations; we often infer the genotypic and environmental conditions that led to the existing host–microbe relationships. However, several outstanding questions remain, including understanding how host and microbial (internal) traits, and ecological and evolutionary (external) processes, influence the origin of beneficial host–microbe associations. Experimental evolution has helped address a range of evolutionary and ecological questions across different model systems; however, it has been greatly underutilized as a tool to study beneficial host–microbe associations. In this review, we suggest ways in which experimental evolution can further our understanding of the proximate and ultimate mechanisms shaping mutualistic interactions between eukaryotic hosts and microbes. By tracking beneficial interactions under defined conditions or evolving novel associations among hosts and microbes with little prior evolutionary interaction, we can link specific genotypes to phenotypes that can be directly measured. Moreover, this approach will help address existing puzzles in beneficial symbiosis research: how symbioses evolve, how symbioses are maintained, and how both host and microbe influence their partner’s evolutionary trajectories. By bridging theoretical predictions and empirical tests, experimental evolution provides us with another approach to test hypotheses regarding the evolution of beneficial host–microbe associations.

  10. A bacterial symbiont is converted from an inedible producer of beneficial molecules into food by a single mutation in the gacA gene

    PubMed Central

    Stallforth, Pierre; Brock, Debra A.; Cantley, Alexandra M.; Tian, Xiangjun; Queller, David C.; Strassmann, Joan E.; Clardy, Jon

    2013-01-01

    Stable multipartite mutualistic associations require that all partners benefit. We show that a single mutational step is sufficient to turn a symbiotic bacterium from an inedible but host-beneficial secondary metabolite producer into a host food source. The bacteria’s host is a “farmer” clone of the social amoeba Dictyostelium discoideum that carries and disperses bacteria during its spore stage. Associated with the farmer are two strains of Pseudomonas fluorescens, only one of which serves as a food source. The other strain produces diffusible small molecules: pyrrolnitrin, a known antifungal agent, and a chromene that potently enhances the farmer’s spore production and depresses a nonfarmer’s spore production. Genome sequence and phylogenetic analyses identify a derived point mutation in the food strain that generates a premature stop codon in a global activator (gacA), encoding the response regulator of a two-component regulatory system. Generation of a knockout mutant of this regulatory gene in the nonfood bacterial strain altered its secondary metabolite profile to match that of the food strain, and also, independently, converted it into a food source. These results suggest that a single mutation in an inedible ancestral strain that served a protective role converted it to a “domesticated” food source. PMID:23898207

  11. Beneficial native bacteria improve survival and mycorrhization of desert truffle mycorrhizal plants in nursery conditions.

    PubMed

    Navarro-Ródenas, Alfonso; Berná, Luis Miguel; Lozano-Carrillo, Cecilia; Andrino, Alberto; Morte, Asunción

    2016-10-01

    Sixty-four native bacterial colonies were isolated from mycorrhizal roots of Helianthemum almeriense colonized by Terfezia claveryi, mycorrhizosphere soil, and peridium of T. claveryi to evaluate their effect on mycorrhizal plant production. Based on the phylogenetic analysis of the 16S rDNA partial sequence, 45 different strains from 17 genera were gathered. The largest genera were Pseudomonas (40.8 % of the isolated strains), Bacillus (12.2 % of isolated strains), and Varivorax (8.2 % of isolated strains). All the bacteria were characterized phenotypically and by their plant growth-promoting rhizobacteria (PGPR) traits (auxin and siderophore production, phosphate solubilization, and ACC deaminase activity). Only bacterial combinations with several PGPR traits or Pseudomonas sp. strain 5, which presents three different PGPR traits, had a positive effect on plant survival and growth. Particularly relevant were the bacterial treatments involving auxin release, which significantly increased the root-shoot ratio and mycorrhizal colonization. Moreover, Pseudomonas mandelii strain 29 was able to considerably increase mycorrhizal colonization but not plant growth, and could be considered as mycorrhiza-helper bacteria. Therefore, the mycorrhizal roots, mycorrhizosphere soil, and peridium of desert truffles are environments enriched in bacteria which may be used to increase the survival and mycorrhization in the desert truffle plant production system at a semi-industrial scale.

  12. Beneficial native bacteria improve survival and mycorrhization of desert truffle mycorrhizal plants in nursery conditions.

    PubMed

    Navarro-Ródenas, Alfonso; Berná, Luis Miguel; Lozano-Carrillo, Cecilia; Andrino, Alberto; Morte, Asunción

    2016-10-01

    Sixty-four native bacterial colonies were isolated from mycorrhizal roots of Helianthemum almeriense colonized by Terfezia claveryi, mycorrhizosphere soil, and peridium of T. claveryi to evaluate their effect on mycorrhizal plant production. Based on the phylogenetic analysis of the 16S rDNA partial sequence, 45 different strains from 17 genera were gathered. The largest genera were Pseudomonas (40.8 % of the isolated strains), Bacillus (12.2 % of isolated strains), and Varivorax (8.2 % of isolated strains). All the bacteria were characterized phenotypically and by their plant growth-promoting rhizobacteria (PGPR) traits (auxin and siderophore production, phosphate solubilization, and ACC deaminase activity). Only bacterial combinations with several PGPR traits or Pseudomonas sp. strain 5, which presents three different PGPR traits, had a positive effect on plant survival and growth. Particularly relevant were the bacterial treatments involving auxin release, which significantly increased the root-shoot ratio and mycorrhizal colonization. Moreover, Pseudomonas mandelii strain 29 was able to considerably increase mycorrhizal colonization but not plant growth, and could be considered as mycorrhiza-helper bacteria. Therefore, the mycorrhizal roots, mycorrhizosphere soil, and peridium of desert truffles are environments enriched in bacteria which may be used to increase the survival and mycorrhization in the desert truffle plant production system at a semi-industrial scale. PMID:27262434

  13. Pseudomonas guangdongensis sp. nov., isolated from an electroactive biofilm, and emended description of the genus Pseudomonas Migula 1894.

    PubMed

    Yang, Guiqin; Han, Luchao; Wen, Junlin; Zhou, Shungui

    2013-12-01

    A Gram-negative, straight to slightly curved rod-shaped bacterium, motile with peritrichous flagella, designated SgZ-6(T), was isolated from an electroactive biofilm and was characterized by means of a polyphasic approach. Growth occurred with 0-5.0 % (w/v) NaCl (optimum 1 %), at pH 6.0-10.0 (optimum pH 7.0) and at 10-42 °C (optimum 30 °C) in trypticase soya broth. Phylogenetic analyses based on the 16S rRNA and gyrB genes identified the isolate as a member of a novel species of the genus Pseudomonas. Strain SgZ-6(T) exhibited the highest 16S rRNA gene sequence similarity to 'Pseudomonas linyingensis' CGMCC 1.10701 (97.5 %), followed by Pseudomonas sagittaria JCM 18195(T) (97.4 %), P. oleovorans subsp. lubricantis DSM 21016(T) (96.6 %), P. tuomuerensis JCM 14085(T) (96.5 %) and P. alcaliphila JCM 10630(T) (96.4 %). Strain SgZ-6(T) showed the highest gyrB gene sequence similarity of 93.7 % to 'P. linyingensis' CGMCC 1.10701 among all type strains of genus Pseudomonas. DNA-DNA pairing studies showed that strain SgZ-6(T) displayed 47.1 and 40.3 % relatedness to 'P. linyingensis' CGMCC 1.10701 and P. sagittaria JCM 18195(T), respectively. The major isoprenoid quinone was ubiquinone 9 (Q-9). The whole-cell fatty acids consisted mainly of summed feature 3 (C16 : 1ω6c and/or C16 : 1ω7c), C16 : 0 and summed feature 8 (C18 : 1ω6c and/or C18 : 1ω7c). The DNA G+C content of the genomic DNA was 68.1 mol%. On the basis of phenotypic, chemotaxonomic and phylogenetic data, strain SgZ-6(T) is proposed to represent a novel species of the genus Pseudomonas, for which the name Pseudomonas guangdongensis sp. nov. is proposed. The type strain is SgZ-6(T) ( = CCTCC AB 2012022(T) = KACC 16606(T)). An emended description of the genus Pseudomonas is also proposed. PMID:23918787

  14. Influence of storage conditions on the growth of Pseudomonas species in refrigerated raw milk.

    PubMed

    De Jonghe, Valerie; Coorevits, An; Van Hoorde, Koenraad; Messens, Winy; Van Landschoot, Anita; De Vos, Paul; Heyndrickx, Marc

    2011-01-01

    The refrigerated storage of raw milk throughout the dairy chain prior to heat treatment creates selective conditions for growth of psychrotolerant bacteria. These bacteria, mainly belonging to the genus Pseudomonas, are capable of producing thermoresistant extracellular proteases and lipases, which can cause spoilage and structural defects in pasteurized and ultra-high-temperature-treated milk (products). To map the influence of refrigerated storage on the growth of these pseudomonads, milk samples were taken after the first milking turn and incubated laboratory scale at temperatures simulating optimal and suboptimal preprocessing storage conditions. The outgrowth of Pseudomonas members was monitored over time by means of cultivation-independent denaturing gradient gel electrophoresis (DGGE). Isolates were identified by a polyphasic approach. These incubations revealed that outgrowth of Pseudomonas members occurred from the beginning of the dairy chain (farm tank) under both optimal and suboptimal storage conditions. An even greater risk for outgrowth, as indicated by a vast increase of about 2 log CFU per ml raw milk, existed downstream in the chain, especially when raw milk was stored under suboptimal conditions. This difference in Pseudomonas outgrowth between optimal and suboptimal storage was already statistically significant within the farm tank. The predominant taxa were identified as Pseudomonas gessardii, Pseudomonas gessardii-like, Pseudomonas fluorescens-like, Pseudomonas lundensis, Pseudomonas fragi, and Pseudomonas fragi-like. Those taxa show an important spoilage potential as determined on elective media for proteolysis and lipolysis. PMID:21115713

  15. Toxicity of fungal-generated silver nanoparticles to soil-inhabiting Pseudomonas putida KT2440, a rhizospheric bacterium responsible for plant protection and bioremediation.

    PubMed

    Gupta, Indarchand R; Anderson, Anne J; Rai, Mahendra

    2015-04-01

    Silver nanoparticles have attracted considerable attention due to their beneficial properties. But toxicity issues associated with them are also rising. The reports in the past suggested health hazards of silver nanoparticles at the cellular, molecular, or whole organismal level in eukaryotes. Whereas, there is also need to examine the exposure effects of silver nanoparticle to the microbes, which are beneficial to humans as well as environment. The available literature suggests the harmful effects of physically and chemically synthesised silver nanoparticles. The toxicity of biogenically synthesized nanoparticles has been less studied than physically and chemically synthesised nanoparticles. Hence, there is a greater need to study the toxic effects of biologically synthesised silver nanoparticles in general and mycosynthesized nanoparticles in particular. In the present study, attempts have been made to assess the risk associated with the exposure of mycosynthesized silver nanoparticles on a beneficial soil microbe Pseudomonas putida. KT2440. The study demonstrates mycosynthesis of silver nanoparticles and their characterisation by UV-vis spectrophotometry, FTIR, X-ray diffraction, nanosight LM20--a particle size distribution analyzer and TEM. Silver nanoparticles obtained herein were found to exert the hazardous effect at the concentration of 0.4 μg/ml, which warrants further detailed investigations concerning toxicity. PMID:25562807

  16. Toxicity of fungal-generated silver nanoparticles to soil-inhabiting Pseudomonas putida KT2440, a rhizospheric bacterium responsible for plant protection and bioremediation.

    PubMed

    Gupta, Indarchand R; Anderson, Anne J; Rai, Mahendra

    2015-04-01

    Silver nanoparticles have attracted considerable attention due to their beneficial properties. But toxicity issues associated with them are also rising. The reports in the past suggested health hazards of silver nanoparticles at the cellular, molecular, or whole organismal level in eukaryotes. Whereas, there is also need to examine the exposure effects of silver nanoparticle to the microbes, which are beneficial to humans as well as environment. The available literature suggests the harmful effects of physically and chemically synthesised silver nanoparticles. The toxicity of biogenically synthesized nanoparticles has been less studied than physically and chemically synthesised nanoparticles. Hence, there is a greater need to study the toxic effects of biologically synthesised silver nanoparticles in general and mycosynthesized nanoparticles in particular. In the present study, attempts have been made to assess the risk associated with the exposure of mycosynthesized silver nanoparticles on a beneficial soil microbe Pseudomonas putida. KT2440. The study demonstrates mycosynthesis of silver nanoparticles and their characterisation by UV-vis spectrophotometry, FTIR, X-ray diffraction, nanosight LM20--a particle size distribution analyzer and TEM. Silver nanoparticles obtained herein were found to exert the hazardous effect at the concentration of 0.4 μg/ml, which warrants further detailed investigations concerning toxicity.

  17. Pseudomonas mosselii sp. nov., a novel species isolated from clinical specimens.

    PubMed

    Dabboussi, Fouad; Hamze, Monzer; Singer, Elisabeth; Geoffroy, Valerie; Meyer, Jean-Marie; Izard, Daniel

    2002-03-01

    Twenty-two fluorescent pseudomonad strains of clinical origin received as Pseudomonas fluorescens (10 strains), Pseudomonasputida (10 strains) and Pseudomonas sp. (2 strains), and 33 type strains of the genus Pseudomonas were studied by numerical analysis based on 280 phenotypic characters. Twelve of the 22 clinical isolates clustered within a specific group, cluster IV. The other strains clustered within groups containing well-characterized fluorescent Pseudomonas species or did not cluster. Strains belonging to cluster IV were phenotypically different from all other clusters and subclusters of fluorescent pseudomonads. DNA-DNA hybridization showed that cluster IV corresponded to a genomic group sharing 72-100% DNA relatedness. DNA-DNA hybridization values with 67 strains representing 30 species of the genus Pseudomonas sensu stricto, including six recently described species (Pseudomonas veronii, Pseudomonas rhodesiae, Pseudomonas libanensis, 'Pseudomonas orientalis', 'Pseudomonas cedrella' and Pseudomonas monteilii), were below 49%, the value found for P. monteilii. The DNA G+C content of the type strain was 63 mol%. Comparison of the 16S rRNA gene sequence of a representative strain of cluster IV (CFML 90-83T) with sequences of other strains of the genus Pseudomonas revealed that strain CFML 90-83T was part of the P. fluorescens intrageneric cluster. On the basis of phenotypic, DNA-DNA hybridization and phylogenetic analyses, a novel species, Pseudomonas mosselii sp. nov., is proposed for the 12 strains of cluster IV. The type strain is P. mosselii CFML 90-83T (= ATCC BAA-99T = CIP 105259T). The P. mosselii strains are phenotypically homogeneous and can be differentiated from other fluorescent species by several phenotypic features, including pyoverdine typing. PMID:11931144

  18. Induction of toluene oxidation activity in pseudomonas mendocina KR1 and pseudomonas sp. strain ENVPC5 by chlorinated solvents and alkanes

    SciTech Connect

    McClay, K.; Streger, S.H.; Steffan, R.J.

    1995-09-01

    Toluene oxidation activity in Pseudomonas mendocina KR1 and Pseudomonas sp. strain ENVPC5 was induced by trichloroethylene (TCE), and induction was followed by the degradation of TCE. Higher levels of toluene oxidation activity were achieved in the presence of a supplemental growth substrate such as glutamate, with levels of activity of up to 86% of that observed with toluene-induced cells. Activity in P. mendocina KR1 was also induced by cis-1,2-dichloroethylene, perchloroethylene, chloroethane, hexane, pentane, and octane, but not by trans-1,2-dichloroethylene. Toluene oxidation was not induced by TCE in Burkholderia (Pseudomonas) cepacia G4, P. putida F1, Pseudomonas sp. strain ENV110, or Pseudomonas sp. strain ENV113. 22 refs., 4 tabs.

  19. Exploiting the Adaptation Dynamics to Predict the Distribution of Beneficial Fitness Effects.

    PubMed

    John, Sona; Seetharaman, Sarada

    2016-01-01

    Adaptation of asexual populations is driven by beneficial mutations and therefore the dynamics of this process, besides other factors, depends on the distribution of beneficial fitness effects. It is known that on uncorrelated fitness landscapes, this distribution can only be of three types: truncated, exponential and power law. We performed extensive stochastic simulations to study the adaptation dynamics on rugged fitness landscapes, and identified two quantities that can be used to distinguish the underlying distribution of beneficial fitness effects. The first quantity studied here is the fitness difference between successive mutations that spread in the population, which is found to decrease in the case of truncated distributions, remains nearly a constant for exponentially decaying distributions and increases when the fitness distribution decays as a power law. The second quantity of interest, namely, the rate of change of fitness with time also shows quantitatively different behaviour for different beneficial fitness distributions. The patterns displayed by the two aforementioned quantities are found to hold good for both low and high mutation rates. We discuss how these patterns can be exploited to determine the distribution of beneficial fitness effects in microbial experiments. PMID:26990188

  20. Exploiting the Adaptation Dynamics to Predict the Distribution of Beneficial Fitness Effects

    PubMed Central

    2016-01-01

    Adaptation of asexual populations is driven by beneficial mutations and therefore the dynamics of this process, besides other factors, depends on the distribution of beneficial fitness effects. It is known that on uncorrelated fitness landscapes, this distribution can only be of three types: truncated, exponential and power law. We performed extensive stochastic simulations to study the adaptation dynamics on rugged fitness landscapes, and identified two quantities that can be used to distinguish the underlying distribution of beneficial fitness effects. The first quantity studied here is the fitness difference between successive mutations that spread in the population, which is found to decrease in the case of truncated distributions, remains nearly a constant for exponentially decaying distributions and increases when the fitness distribution decays as a power law. The second quantity of interest, namely, the rate of change of fitness with time also shows quantitatively different behaviour for different beneficial fitness distributions. The patterns displayed by the two aforementioned quantities are found to hold good for both low and high mutation rates. We discuss how these patterns can be exploited to determine the distribution of beneficial fitness effects in microbial experiments. PMID:26990188

  1. Investigation of MCHM transport mechanisms and fate: implications for coal beneficiation.

    PubMed

    He, Y Thomas; Noble, Aaron; Ziemkiewicz, Paul

    2015-05-01

    4-Methyl cyclohexane methanol (MCHM) is a flotation reagent often used in fine coal beneficiation and notably involved in the January 9, 2014 Elk River chemical spill in Charleston, WV. This study investigates the mechanisms controlling the transport and fate of MCHM in coal beneficiation plants and surrounding environments. Processes such as volatilization, sorption, and leaching were evaluated through laboratory batch and column experiments. The results indicate volatilization and sorption are important mechanisms which influence the removal of MCHM from water, with sorption being the most significant removal mechanism over short time scales (<1 h). Additionally, leaching experiments show both coal and tailings have high affinity for MCHM, and this reagent does not desorb readily. Overall, the results from these experiments indicate that MCHM is either volatilized or sorbed during coal beneficiation, and it is not likely to transport out of coal beneficiation plant. Thus, use of MCHM in coal beneficiation plant is not likely to pose threat to either surface or groundwater under normal operating conditions.

  2. Pseudomonas oleovorans subsp. lubricantis subsp. nov., and reclassification of Pseudomonas pseudoalcaligenes ATCC 17440T as later synonym of Pseudomonas oleovorans ATCC 8062 T.

    PubMed

    Saha, Ratul; Spröer, Cathrin; Beck, Brian; Bagley, Susan

    2010-04-01

    Isolate RS1(T) isolated from used metalworking fluid was found to be a Gram-negative, motile, and non-spore forming rod. Based on phylogenetic analyses with 16S rRNA, isolate RS1(T) was placed into the mendocina sublineage of Pseudomonas. The major whole cell fatty acids were C(18:1)omega7c (32.6%), C(16:0) (25.5%), and C(15:0) ISO 2OH/C(16:1)omega7c (14.4%). The sequence similarities of isolate RS1(T) based on gyrB and rpoD genes were 98.9 and 98.0% with Pseudomonas pseudoalcaligenes, and 98.5 and 98.1% with Pseudomonas oleovorans, respectively. The ribotyping pattern showed a 0.60 similarity with P. oleovorans ATCC 8062(T) and 0.63 with P. pseudoalcaligenes ATCC17440(T). The DNA G + C content of isolate RS1(T) was 62.2 mol.%. The DNA-DNA relatedness was 73.0% with P. oleovorans ATCC 8062(T) and 79.1% with P. pseudoalcaligenes ATCC 17440(T). On the basis of morphological, biochemical, and molecular studies, isolate RS1(T) is considered to represent a new subspecies of P. oleovorans. Furthermore, based on the DNA-DNA relatedness (>70%), chemotaxonomic, and molecular profile, P. pseudoalcaligenes ATCC 17440(T) and P. oleovorans ATCC 8062(T) should be united under the same name; according to the rules of priority, P. oleovorans, the first described species, is the earlier synonym and P. pseudoalcaligenes is the later synonym. As a consequence, the division of the species P. oleovorans into two novel subspecies is proposed: P. oleovorans subsp. oleovorans subsp. nov. (type strain ATCC 8062(T) = DSM 1045(T) = NCIB 6576(T)), P. oleovorans subsp. lubricantis subsp. nov. (type strain RS1(T) = ATCC BAA-1494(T) = DSM 21016(T)). PMID:19936829

  3. Simple DNA transformation in Pseudomonas based on the Yoshida effect.

    PubMed

    Rodríguez-Beltrán, Jerónimo; Elabed, Hamouda; Gaddour, Kamel; Blázquez, Jesús; Rodríguez-Rojas, Alexandro

    2012-05-01

    Current protocols of recombinant DNA research, including gene cloning and complementation, quantification of gene expression and tagging with reporter proteins, are usually limited by the availability of effective bacteria transformation tools different from Escherichia coli. This is particularly relevant with respect to the Pseudomonas species due to their biotechnological and sanitary importance. Here, we describe an optimized and efficient plasmid transference protocol based on the Yoshida effect, a method that relies on DNA uptake mediated by friction forces. The main advantages of this method are: (i) no competent cell preparation is needed, (ii) cells in any physiological state can be used, (iii) the procedure is performed directly on agar plates and (iv) the protocol, which is neither time-consuming nor labor-intensive, offers good efficiency. This approach promises to become the gold standard for day to day genetic manipulation in Pseudomonas.

  4. Homology study of two polyhydroxyalkanoate (PHA) synthases from Pseudomonas aureofaciens.

    PubMed

    Umeda, F; Nishikawa, T; Miyasaka, H; Maeda, I; Kawase, M; Yagi, K

    2001-11-01

    Recently, we have cloned and analyzed two polyhydroxyalkanoate (PHA) synthase genes (phaC1 and phaC2 in the pha cluster) from Pseudomonas aureofaciens. In this report, the deduced amino acid (AA) sequences of PHA synthase 1 and PHA synthase 2 from P. aureofaciens are compared with those from three other bacterial strains (Pseudomonas sp. 61-3, P. oleovorans and P. aeruginosa) containing the homologous pha cluster. The level of homology of either PHA synthase 1 or PHA synthase 2 was high with each enzyme from these three bacterial strains. Furthermore, multialignment of PHA synthase AA sequences implied that both enzymes of PHA synthase 1 and PHA synthase 2 were highly conserved in the four strains including P. aureofaciens. PMID:11916262

  5. Genomic plasticity and catabolic potential of Pseudomonas cepacia

    SciTech Connect

    Lessie, T.G.

    1996-04-01

    The primary goal of this project was to gain information about the size and organization of the genome of Burkholderia cepacia (formerly Pseudomonas cepacia), a microbe which continues to attract attention because of its extraordinary degradative abilities and potential as an agent of bioremediation. This bacterium is no longer considered to be a member of genus Pseudomonas nor does it belong in the gamma-subclass of the proteobacteria, in which the authentic pseudomonads are grouped. It belongs in the less well characterized beta-subclass of the proteobacteria. Technology for manipulation of large DNA fragments developed by Cantor was used to demonstrate that chromosomal multiplicity, a characteristic yet to be observed in a gamma-subclass bacterium, is common among B. cepacia strains. A derivative of Tn5 suitable for determining the chromosomal locations of various B. cepacia genes was also constructed.

  6. Agricultural plants and soil as a reservoir for Pseudomonas aeruginosa.

    PubMed

    Green, S K; Schroth, M N; Cho, J J; Kominos, S K; Vitanza-jack, V B

    1974-12-01

    Pseudomonas aeruginosa was detected in 24% of the soil samples but in only 0.13% of the vegetable samples from various agricultural areas of California. The distribution of pyocin types of soil and vegetable isolates was similar to that of clinical strains, and three of the soil isolates were resistant to carbenicillin. Pseudomonas aeruginosa multiplied in lettuce and bean under conditions of high temperature and high relative humidity (27 C and 80-95% relative humidity) but declined when the temperature and humidity were lowered (16 C, 55-75% relative humidity). The results suggest that soil is a reservior for P. aeruginosa and that the bacterium has the capacity to colonize plants during favorable conditions of temperature and moisture. PMID:4217591

  7. Membrane proteomes of Pseudomonas aeruginosa and Acinetobacter baumannii.

    PubMed

    Dé, E; Cosette, P; Coquet, L; Siroy, A; Alexandre, S; Duncan, A; Naudin, B; Rihouey, C; Schaumann, A; Junter, G A; Jouenne, T

    2011-12-01

    Acinetobacter baumannii and Pseudomonas aeruginosa are known for their intrinsic resistance to antibiotics. Between mechanisms involved in this resistance, diminished expression of outer membrane proteins and up-regulation of efflux pumps play an important role. The characterization of membrane proteins is consequently necessary because of their importance in the antibiotic resistance but also in virulence. This review presents proteomic investigations aiming to describe the protein content of the membranes of these two bacterial species. PMID:19942379

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

    SciTech Connect

    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.

  9. Empyema Caused by Pseudomonas luteola: A Case Report

    PubMed Central

    Yousefi, Farid; Shoja, Saeed; Honarvar, Negin

    2014-01-01

    Introduction: Pseudomonas luteola is an uncommon opportunistic pathogen. It is recognized as an uncommon cause of infections in underlying medical disorders. Infections caused by this microorganism are health care associated. Case Presentation: The current study isolated P. luteola from empyema in a patient with tuberculous pleurisy, whose susceptibility to trimethoprim-sulfamethoxazole differed from previous reports. Conclusions: P. luteola is resistant to TMP-SMX, but in the present case P. luteola was susceptible to TMP-SMX PMID:25368791

  10. Membrane proteomes of Pseudomonas aeruginosa and Acinetobacter baumannii.

    PubMed

    Dé, E; Cosette, P; Coquet, L; Siroy, A; Alexandre, S; Duncan, A; Naudin, B; Rihouey, C; Schaumann, A; Junter, G A; Jouenne, T

    2011-12-01

    Acinetobacter baumannii and Pseudomonas aeruginosa are known for their intrinsic resistance to antibiotics. Between mechanisms involved in this resistance, diminished expression of outer membrane proteins and up-regulation of efflux pumps play an important role. The characterization of membrane proteins is consequently necessary because of their importance in the antibiotic resistance but also in virulence. This review presents proteomic investigations aiming to describe the protein content of the membranes of these two bacterial species.

  11. Iron-regulated salicylate synthesis by Pseudomonas spp.

    PubMed

    Visca, P; Ciervo, A; Sanfilippo, V; Orsi, N

    1993-09-01

    Two iron-regulated compounds have been found in acidified ethyl acetate extracts from culture supernatants of Pseudomonas aeruginosa and Pseudomonas cepacia type-strains. Synthesis of both compounds paralleled iron-deficient growth, and was repressed in the presence of 100 microM-FeCl3. Yields of these substances varied among different strains and attained maximum levels during stationary phase. Thin layer chromatographic analysis in five different solvent systems revealed that the slower-moving compound chromatographed as two distinct bands, and showed RF values and spectral properties similar to pyochelin. The faster-moving compound co-migrated as a single band with a standard of commercial salicylic acid in each of the chromatographic systems tested. Moreover, a molecule with an identical RF was also produced by Pseudomonas fluorescens CHA401, which is known to synthesize salicylic acid as the only siderophore during iron-limited growth. Spectrophotometric and spectrofluorometric titrations led to the identification of this iron-regulated compound as salicylic acid, in agreement with the structure deduced from 1H-NMR and mass spectroscopy. The identity of the P. cepacia siderophore azurechelin as salicylic acid was also conclusively demonstrated. Salicylic acid, like pyochelin and pyoverdin, promoted P. aeruginosa growth in an iron-depleted medium. These results are consistent with a putative siderophore activity for salicylic acid, i.e. azurechelin, as has been demonstrated for P. aeruginosa, P. fluorescens and P. cepacia. Thus, salicylic acid is likely to act as a siderophore in more than one species belonging to the genus Pseudomonas. PMID:7504066

  12. Biodegradation of 4-nitrotoluene by pseudomonas sp. strain 4NT

    SciTech Connect

    Haigler, B.E.; Spain, J.C. )

    1993-07-01

    Nitroaromatic compounds, common intermediates or by-products in synthesis of dyes, solvents, and explosives, has resulting in their emergence as environmental contaminants. Bacterial strains able to degrade 4-nitrotoluene (4-NT) have been isolated. The present study reports the complete degradative pathway of Pseudomonas sp. strain 4NT that uses 4-NT as a sole source of carbon, nitrogen, and energy. 33 refs., 2 figs., 3 tabs.

  13. Pyochelin potentiates the inhibitory activity of gallium on Pseudomonas aeruginosa.

    PubMed

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

    2014-09-01

    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.

  14. Pyochelin potentiates the inhibitory activity of gallium on Pseudomonas aeruginosa.

    PubMed

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

    2014-09-01

    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

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

    NASA Astrophysics Data System (ADS)

    Attard, E.; Yang, H.; Delort, A.-M.; Amato, P.; Pöschl, U.; Glaux, C.; Koop, T.; Morris, C. E.

    2012-11-01

    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.

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

    NASA Astrophysics Data System (ADS)

    Attard, E.; Yang, H.; Delort, A.-M.; Amato, P.; Pöschl, U.; Glaux, C.; Koop, T.; Morris, C. E.

    2012-04-01

    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.

  17. Enzyme-linked immunosorbent assay for detection of antibodies to Pseudomonas aeruginosa exoproteins.

    PubMed

    Granström, M; Wretlind, B; Markman, B; Pavlovskis, O R; Vasil, M L

    1985-04-01

    Enzyme-linked immunosorbent assays were developed with four purified Pseudomonas aeruginosa extracellular proteins (exotoxin A, elastase, alkaline protease, and phospholipase C) to determine antibody levels in sera from healthy subjects and the serological response in patients colonized or infected with Pseudomonas aeruginosa. Five of 39 burn patients with wounds colonized by Pseudomonas aeruginosa had elevated antibody titers to alkaline protease. Response to the other antigens was found in only a few patients. Pseudomonas aeruginosa infections (septicemia, osteitis, pneumonia etc.) resulted in increased antibody levels to exotoxin A or phospholipase C in 15 of 22 patients. These findings suggest that repeated determinations of antibodies to Pseudomonas aeruginosa exotoxin A and phospholipase C might be used to monitor therapy in certain patients with osteitis and other deep Pseudomonas infections.

  18. The phylogeny of the genera Chryseomonas, Flavimonas, and Pseudomonas supports synonymy of these three genera.

    PubMed

    Anzai, Y; Kudo, Y; Oyaizu, H

    1997-04-01

    The 16S rRNA sequences of Chryseomonas luteola, the type species of the genus Chryseomonas, and Flavimonas oryzihabitans, the type species of the genus Flavimonas, were determined. These sequences were compared with the sequences of 27 representative strains of the genus Pseudomonas. C. luteola and F. oryzihabitans were located in the cluster that contains Pseudomonas aeruginosa, the type species of genus Pseudomonas Migula 1894, and the levels of 16S rRNA sequence homology between P. aeruginosa and the other two species were more than 93.9%. All of the strains of the genus Pseudomonas sensu stricto whose sequences have been determined were included in the P. aeruginosa cluster. These results suggested that Chryseomonas, Flavimonas, and Pseudomonas are synonymous, and we concluded that Chryseomonas and Flavimonas are junior subjective synonyms of Pseudomonas.

  19. The phylogeny of the genera Chryseomonas, Flavimonas, and Pseudomonas supports synonymy of these three genera.

    PubMed

    Anzai, Y; Kudo, Y; Oyaizu, H

    1997-04-01

    The 16S rRNA sequences of Chryseomonas luteola, the type species of the genus Chryseomonas, and Flavimonas oryzihabitans, the type species of the genus Flavimonas, were determined. These sequences were compared with the sequences of 27 representative strains of the genus Pseudomonas. C. luteola and F. oryzihabitans were located in the cluster that contains Pseudomonas aeruginosa, the type species of genus Pseudomonas Migula 1894, and the levels of 16S rRNA sequence homology between P. aeruginosa and the other two species were more than 93.9%. All of the strains of the genus Pseudomonas sensu stricto whose sequences have been determined were included in the P. aeruginosa cluster. These results suggested that Chryseomonas, Flavimonas, and Pseudomonas are synonymous, and we concluded that Chryseomonas and Flavimonas are junior subjective synonyms of Pseudomonas. PMID:9103607

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

    PubMed Central

    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. PMID:26300874