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Sample records for bacterium pseudomonas putida

  1. Breeding of a cyclic imide-assimilating bacterium, Pseudomonas putida s52, for high efficiency production of pyruvate.

    Science.gov (United States)

    Hibi, Makoto; Horinouchi, Nobuyuki; Tu, Weihao; Soong, Chee-Leong; Ito, Masashi; Segawa, Toshinori; Mu, Xiaoqing; Hagishita, Tairo; Yokozeki, Kenzo; Shimizu, Sakayu; Ogawa, Jun

    2013-01-01

    A succinimide-assimilating bacterium, Pseudomonas putida s52, was found to be a potent producer of pyruvate from fumarate. Using washed cells from P. putida s52 as catalyst, 400 mM pyruvate was produced from 500 mM fumarate in a 36-h reaction. Bromopyruvate, a malic enzyme inhibitor, was used for the selection of mutants with higher pyruvate productivity. A bromopyruvate-resistant mutant, P. putida 15160, was found to be an effective catalyst for pyruvate production. Moreover, under batch bioreactor conditions, 767 mM of pyruvate was successfully produced from 1,000 mM fumarate in a 72-h reaction with washed cells from P. putida 15160 as catalyst. PMID:23924711

  2. Genome Sequence of Pseudomonas putida Idaho, a Unique Organic-Solvent-Tolerant Bacterium

    OpenAIRE

    Tao, Fei; Tang, Hongzhi; Gai, Zhonghui; Su, Fei; Wang, Xiaoyu; He, Xiaofei; Xu, Ping

    2011-01-01

    Pseudomonas putida Idaho is an organic-solvent-tolerant strain which can degrade and adapt to high concentrations of organic solvents. Here, we announce its first draft genome sequence (6,363,067 bp). We annotated 192 coding sequences (CDSs) responsible for aromatic compound metabolism, 40 CDSs encoding phospholipid synthesis, and 212 CDSs related to stress response.

  3. Pyoverdine synthesis by the Mn(II-oxidizing bacterium Pseudomonas putida GB-1

    Directory of Open Access Journals (Sweden)

    Sung-WooLee

    2014-05-01

    Full Text Available When iron-starved, the Mn(II-oxidizing bacteria Pseudomonas putida strains GB-1 and MnB1 produce pyoverdines (PVDGB-1 and PVDMnB1, siderophores that both influence iron uptake and inhibit manganese(II oxidation by these strains. To explore the properties and genetics of a PVD that can affect manganese oxidation, LC-MS/MS and various siderotyping techniques were used to identify the peptides of PVDGB-1 and PVDMnB1 as being (for both PVDs: chromophore-Asp-Lys-OHAsp-Ser-Gly-aThr-Lys-cOHOrn, resembling a structure previously reported for P. putida CFML 90-51, which does not oxidize Mn. All three strains also produced an azotobactin and a sulfonated PVD, each with the peptide sequence above, but with unknown regulatory or metabolic effects. Bioinformatic analysis of the sequenced genome of P. putida GB-1 suggested that a particular non-ribosomal peptide synthetase, coded by the operon PputGB1_4083-4086, could produce the peptide backbone of PVDGB-1. To verify this prediction, plasmid integration disruption of PputGB1_4083 was performed and the resulting mutant failed to produce detectable PVD. In silico analysis of the modules in PputGB1_4083-4086 predicted a peptide sequence of Asp-Lys-Asp-Ser-Ala-Thr-Lsy-Orn, which closely matches the peptide determined by MS/MS. To extend these studies to other organisms, various Mn(II-oxidizing and non-oxidizing isolates of P. putida, P. fluorescens, P. marincola, P. fluorescens-syringae group, P. mendocina-resinovorans group and P. stutzerii group were screened for PVD synthesis. The PVD producers (12 out of 16 tested strains were siderotyped and placed into four sets of differing PVD structures, some corresponding to previously characterized PVDs and some to novel PVDs. These results combined with previous studies suggested that the presence of OHAsp or the flexibility of the pyoverdine polypeptide may enable efficient binding of Mn(III.

  4. Small Rna Regulatory Networks In Pseudomonas Putida

    DEFF Research Database (Denmark)

    Bojanovic, Klara; Long, Katherine

    2015-01-01

    Pseudomonas putida is a ubiquitous Gram-negative soil bacterium with a versatile metabolism and ability to degrade various toxic compounds. It has a high tolerance to different future biobased building blocks and various other stringent conditions. It is used in industry to produce some important...

  5. Display of a thermostable lipase on the surface of a solvent-resistant bacterium, Pseudomonas putida GM730, and its applications in whole-cell biocatalysis

    Directory of Open Access Journals (Sweden)

    Kwon Seok-Joon

    2006-04-01

    Full Text Available Abstract Background Whole-cell biocatalysis in organic solvents has been widely applied to industrial bioprocesses. In two-phase water-solvent processes, substrate conversion yields and volumetric productivities can be limited by the toxicity of solvents to host cells and by the low mass transfer rates of the substrates from the solvent phase to the whole-cell biocatalysts in water. Results To solve the problem of solvent toxicity, we immobilized a thermostable lipase (TliA from Pseudomonas fluorescens on the cell surface of a solvent-resistant bacterium, Pseudomonas putida GM730. Surface immobilization of enzymes eliminates the mass-transfer limitation imposed by the cell wall and membranes. TliA was successfully immobilized on the surface of P. putida cells using the ice-nucleation protein (INP anchoring motif from Pseudomonas syrinage. The surface location was confirmed by flow cytometry, protease accessibility and whole-cell enzyme activity using a membrane-impermeable substrate. Three hundred and fifty units of whole-cell hydrolytic activity per gram dry cell mass were obtained when the enzyme was immobilized with a shorter INP anchoring motif (INPNC. The surface-immobilized TliA retained full enzyme activity in a two-phase water-isooctane reaction system after incubation at 37°C for 12 h, while the activity of the free form enzyme decreased to 65% of its initial value. Whole cells presenting immobilized TliA were shown to catalyze three representative lipase reactions: hydrolysis of olive oil, synthesis of triacylglycerol and chiral resolution. Conclusion In vivo surface immobilization of enzymes on solvent-resistant bacteria was demonstrated, and appears to be useful for a variety of whole-cell bioconversions in the presence of organic solvents.

  6. Chromium reduction in Pseudomonas putida.

    OpenAIRE

    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.

  7. Chromium reduction in Pseudomonas putida.

    Science.gov (United States)

    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

  8. Digestion of algin by Pseudomonas maltophilia and Pseudomonas putida.

    OpenAIRE

    von Riesen, V L

    1980-01-01

    Pseudomonas maltophilia and Pseudomonas putida were identified as alginolytic species. Two media used for demonstrating alginolytic activity are described. The applied aspects of the ability of these two species to digest algin are discussed.

  9. Methylmercury degradation by Pseudomonas putida V1.

    Science.gov (United States)

    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

  10. Toxicity of fungal-generated silver nanoparticles to soil-inhabiting Pseudomonas putida KT2440, a rhizospheric bacterium responsible for plant protection and bioremediation

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, Indarchand R. [Nanobiotechnology Laboratory, Department of Biotechnology, S.G.B. Amravati University, Amravati 444602, Maharashtra (India); Department of Biotechnology, Institute of Science, Nipat Niranjan Nagar, Caves Road, Aurangabad 431004, Maharashtra (India); Anderson, Anne J. [Department of Biology, Utah State University, Logan, Utah 84321 (United States); Rai, Mahendra, E-mail: mahendrarai@sgbau.ac.in [Nanobiotechnology Laboratory, Department of Biotechnology, S.G.B. Amravati University, Amravati 444602, Maharashtra (India); Laboratório de Química Biológica, Instituto de Química, UNICAMP, Cidade Universitária “Zefferino Vaz” Barão Geraldo, CEP 13083-970, Caixa Postal 6150, Campinas, SP (Brazil)

    2015-04-09

    Highlights: • This study incorporates the mycosynthesis of AgNPs and their characterisation by various methods. • A first attempt demonstrating the toxicity assessment of AgNPs on beneficial soil microbe. • Use of biosensor in Pseudomonas putida KT2440, gave accurate antimicrobial results. - Abstract: 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.

  11. Toxicity of fungal-generated silver nanoparticles to soil-inhabiting Pseudomonas putida KT2440, a rhizospheric bacterium responsible for plant protection and bioremediation

    International Nuclear Information System (INIS)

    Highlights: • This study incorporates the mycosynthesis of AgNPs and their characterisation by various methods. • A first attempt demonstrating the toxicity assessment of AgNPs on beneficial soil microbe. • Use of biosensor in Pseudomonas putida KT2440, gave accurate antimicrobial results. - Abstract: 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

  12. Pseudomonas putida Stimulates Primordia on Agaricus bitorquis.

    Science.gov (United States)

    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. Comparative genomic and functional analyses: unearthing the diversity and specificity of nematicidal factors in Pseudomonas putida strain 1A00316.

    Science.gov (United States)

    Guo, Jing; Jing, Xueping; Peng, Wen-Lei; Nie, Qiyu; Zhai, Yile; Shao, Zongze; Zheng, Longyu; Cai, Minmin; Li, Guangyu; Zuo, Huaiyu; Zhang, Zhitao; Wang, Rui-Ru; Huang, Dian; Cheng, Wanli; Yu, Ziniu; Chen, Ling-Ling; Zhang, Jibin

    2016-01-01

    We isolated Pseudomonas putida (P. putida) strain 1A00316 from Antarctica. This bacterium has a high efficiency against Meloidogyne incognita (M. incognita) in vitro and under greenhouse conditions. The complete genome of P. putida 1A00316 was sequenced using PacBio single molecule real-time (SMRT) technology. A comparative genomic analysis of 16 Pseudomonas strains revealed that although P. putida 1A00316 belonged to P. putida, it was phenotypically more similar to nematicidal Pseudomonas fluorescens (P. fluorescens) strains. We characterized the diversity and specificity of nematicidal factors in P. putida 1A00316 with comparative genomics and functional analysis, and found that P. putida 1A00316 has diverse nematicidal factors including protein alkaline metalloproteinase AprA and two secondary metabolites, hydrogen cyanide and cyclo-(l-isoleucyl-l-proline). We show for the first time that cyclo-(l-isoleucyl-l-proline) exhibit nematicidal activity in P. putida. Interestingly, our study had not detected common nematicidal factors such as 2,4-diacetylphloroglucinol (2,4-DAPG) and pyrrolnitrin in P. putida 1A00316. The results of the present study reveal the diversity and specificity of nematicidal factors in P. putida strain 1A00316. PMID:27384076

  14. Comparative genomic and functional analyses: unearthing the diversity and specificity of nematicidal factors in Pseudomonas putida strain 1A00316

    Science.gov (United States)

    Guo, Jing; Jing, Xueping; Peng, Wen-Lei; Nie, Qiyu; Zhai, Yile; Shao, Zongze; Zheng, Longyu; Cai, Minmin; Li, Guangyu; Zuo, Huaiyu; Zhang, Zhitao; Wang, Rui-Ru; Huang, Dian; Cheng, Wanli; Yu, Ziniu; Chen, Ling-Ling; Zhang, Jibin

    2016-01-01

    We isolated Pseudomonas putida (P. putida) strain 1A00316 from Antarctica. This bacterium has a high efficiency against Meloidogyne incognita (M. incognita) in vitro and under greenhouse conditions. The complete genome of P. putida 1A00316 was sequenced using PacBio single molecule real-time (SMRT) technology. A comparative genomic analysis of 16 Pseudomonas strains revealed that although P. putida 1A00316 belonged to P. putida, it was phenotypically more similar to nematicidal Pseudomonas fluorescens (P. fluorescens) strains. We characterized the diversity and specificity of nematicidal factors in P. putida 1A00316 with comparative genomics and functional analysis, and found that P. putida 1A00316 has diverse nematicidal factors including protein alkaline metalloproteinase AprA and two secondary metabolites, hydrogen cyanide and cyclo-(l-isoleucyl-l-proline). We show for the first time that cyclo-(l-isoleucyl-l-proline) exhibit nematicidal activity in P. putida. Interestingly, our study had not detected common nematicidal factors such as 2,4-diacetylphloroglucinol (2,4-DAPG) and pyrrolnitrin in P. putida 1A00316. The results of the present study reveal the diversity and specificity of nematicidal factors in P. putida strain 1A00316. PMID:27384076

  15. Genomotyping of Pseudomonas putida strains using P. putida KT2440-based high-density DNA microarrays: Implications for transcriptomics studies

    NARCIS (Netherlands)

    Ballerstedt, H.; Volkers, R.J.M.; Mars, A.E.; Hallsworth, J.E.; Santos, V.A.M.D.; Puchalka, J.; Duuren, J. van; Eggink, G.; Timmis, K.N.; Bont, J.A.M. de; Wery, J.

    2007-01-01

    Pseudomonas putida KT2440 is the only fully sequenced P. putida strain. Thus, for transcriptomics and proteomics studies with other P. putida strains, the P. putida KT2440 genomic database serves as standard reference. The utility of KT2440 whole-genome, high-density oligonucleotide microarrays for

  16. Characterization of starvation-induced dispersion in Pseudomonas putida biofilms

    DEFF Research Database (Denmark)

    Gjermansen, Morten; Ragas, Paula Cornelia; Sternberg, Claus;

    2005-01-01

    that they must be able to regulate their ability to form biofilm and to dissolve biofilm. We present an investigation of a biofilm dissolution process occurring in flow-chamber-grown Pseudomonas putida biofilms. Local starvation-induced biofilm dissolution appears to be an integrated part of P. putida...

  17. Analysis of Dibenzothiophene Desulfurization in a Recombinant Pseudomonas putida Strain▿

    OpenAIRE

    Calzada, Javier; Zamarro, María T.; Alcón, A.; Santos, Victoria E.; Díaz, Eduardo; García, José L.; García-Ochoa, Félix

    2008-01-01

    Biodesulfurization was monitored in a recombinant Pseudomonas putida CECT5279 strain. DszB desulfinase activity reached a sharp maximum at the early exponential phase, but it rapidly decreased at later growth phases. A model two-step resting-cell process combining sequentially P. putida cells from the late and early exponential growth phases was designed to significantly increase biodesulfurization.

  18. Comparative genomics of an endophytic Pseudomonas putida isolated from mango orchard

    Science.gov (United States)

    Asif, Huma; Studholme, David J.; Khan, Asifullah; Aurongzeb, M.; Khan, Ishtiaq A.; Azim, M. Kamran

    2016-01-01

    Abstract We analyzed the genome sequence of an endophytic bacterial strain Pseudomonas putida TJI51 isolated from mango bark tissues. Next generation DNA sequencing and short read de novo assembly generated the 5,805,096 bp draft genome of P. putida TJI51. Out of 6,036 protein coding genes in P. putida TJI51 sequences, 4,367 (72%) were annotated with functional specifications, while the remaining encoded hypothetical proteins. Comparative genome sequence analysis revealed that the P. putida TJI51genome contains several regions, not identified in so far sequenced P. putida genomes. Some of these regions were predicted to encode enzymes, including acetylornithine deacetylase, betaine aldehyde dehydrogenase, aldehyde dehydrogenase, benzoylformate decarboxylase, hydroxyacylglutathione hydrolase, and uroporphyrinogen decarboxylase. The genome of P. putida TJI51 contained three nonribosomal peptide synthetase gene clusters. Genome sequence analysis of P. putidaTJI51 identified this bacterium as an endophytic resident. The endophytic fitness might be linked with alginate, which facilitates bacterial colonization in plant tissues. Genome sequence analysis shed light on the presence of a diverse spectrum of metabolic activities and adaptation of this isolate to various niches. PMID:27560648

  19. Metabolism-dependent taxis and control of motility in Pseudomonas putida

    OpenAIRE

    Österberg, Sofia

    2013-01-01

    Bacteria living in soil and aquatic habitats rapidly adapt to changes in physico-chemical parameters that influence their energy status and thus their ability to proliferate and survive. One immediate survival strategy is to relocate to more metabolically optimal environments. To aid their movement through gradients (a process called taxis), many bacteria use whip like flagella organelles. Soil-dwelling Pseudomonas putida possesses a polar bundle of flagella that propel the bacterium forward ...

  20. Functional analysis of aromatic biosynthetic pathways in Pseudomonas putida KT2440

    OpenAIRE

    Molina‐Henares, M. Antonia; García‐Salamanca, Adela; Molina‐Henares, A. Jesús; De La Torre, Jesús; Herrera, M?? Carmen; Ramos, Juan L.; Duque, Estrella

    2008-01-01

    Summary Pseudomonas putida KT2440 is a non‐pathogenic prototrophic bacterium with high potential for biotechnological applications. Despite all that is known about this strain, the biosynthesis of essential chemicals has not been fully analysed and auxotroph mutants are scarce. We carried out massive mini‐Tn5 random mutagenesis and screened for auxotrophs that require aromatic amino acids. The biosynthesis of aromatic amino acids was analysed in detail including physical and transcriptional o...

  1. Electricity Generation and Wastewater Treatment of Oil Refinery in Microbial Fuel Cells Using Pseudomonas putida

    OpenAIRE

    Dip Majumder; Jyoti Prakash Maity; Min-Jen Tseng; Vanita Roshan Nimje; Hau-Ren Chen; Chien-Cheng Chen; Young-Fo Chang; Tsui-Chu Yang; Chen-Yen Chen

    2014-01-01

    Microbial fuel cells (MFCs) represent a novel platform for treating wastewater and at the same time generating electricity. Using Pseudomonas putida (BCRC 1059), a wild-type bacterium, we demonstrated that the refinery wastewater could be treated and also generate electric current in an air-cathode chamber over four-batch cycles for 63 cumulative days. Our study indicated that the oil refinery wastewater containing 2213 mg/L (ppm) chemical oxygen demand (COD) could be used as a substrate ...

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

    OpenAIRE

    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.

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

    DEFF Research Database (Denmark)

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

    2003-01-01

    methods, the sigma(54) regulon has been studied both in Escherichia coli, Salmonella typhimurium and several species of the Rhizobiaceae. Here we present the analysis of the sigma(54) regulon (sigmulon) in the complete genome of Pseudomonas putida KT2440. We have developed an improved method for the...

  4. Biological production of monoethanolamine by engineered Pseudomonas putida S12

    NARCIS (Netherlands)

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

    2013-01-01

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

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

    NARCIS (Netherlands)

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

    1993-01-01

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

  6. Biological manganese oxidation by Pseudomonas putida in trickling filters.

    Science.gov (United States)

    McKee, Kyle P; Vance, Cherish C; Karthikeyan, Raghupathy

    2016-06-01

    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). PMID:26943637

  7. Proteins with GGDEF and EAL domains regulate Pseudomonas putida biofilm formation and dispersal

    DEFF Research Database (Denmark)

    Gjermansen, Morten; Ragas, Paula Cornelia; Tolker-Nielsen, Tim

    2006-01-01

    EAL domains are involved in the regulation of biofilm formation and biofilm dispersion in Pseudomonas putida. Overexpression in P. putida of the Escherichia coli YedQ protein, which contains a GGDEF domain, resulted in increased biofilm formation. Overexpression in P. putida of the E. coli Yhj...... regulating the transition of bacteria between a roaming lifestyle and a sessile biofilm lifestyle....

  8. The taxonomy of Pseudomonas fluorescens and Pseudomonas putida: current status and need for revision

    OpenAIRE

    Bossis, Emmanuel; Lemanceau, Philippe; Latour, Xavier; Gardan, Louis

    2000-01-01

    International audience Many studies are devoted to the ecology of Pseudomonas fluorescens and Pseudomonas putida. Indeed, bacteria belonging to these species could potentially be used for environmental purposes. Some strains are able to improve plant growth and plant health, and consequently could contribute to reduce the use of chemical inputs in agriculture. Others are able to dissimilate nitrates and to degrade xenobiotic compounds. Accurate identification of the bacterial strains teste...

  9. Water stress effects on toluene biodegradation by Pseudomonas putida.

    Science.gov (United States)

    Holden, P A; Halverson, L J; Firestone, M K

    1997-01-01

    We quantified the effects of matric and solute water potential on toluene biodegradation by Pseudomonas putida mt-2, a bacterial strain originally isolated from soil. Across the matric potential range of 0 to -1.5 MPa, growth rates were maximal for P. putida at -0.25 MPa and further reductions in the matric potential resulted in concomitant reductions in growth rates. Growth rates were constant over the solute potential range 0 to -1.0 MPa and lower at -1.5 MPa. First order toluene depletion rate coefficients were highest at 0.0 MPa as compared to other matric water potentials down to -1.5 MPa. Solute potentials down to -1.5 MPa did not affect first order toluene depletion rate coefficients. Total yield (protein) and carbon utilization efficiency were not affected by water potential, indicating that water potentials common to temperate soils were not sufficiently stressful to change cellular energy requirements. We conclude that for P. putida: (1) slightly negative matric potentials facilitate faster growth rates on toluene but more negative water potentials result in slower growth, (2) toluene utilization rate per cell mass is highest without matric water stress and is unaffected by solute potential, (3) growth efficiency did not differ across the range of matric water potentials 0.0 to -1.5 MPa. PMID:9396169

  10. Studies on the Production of Rhamnolipids by Pseudomonas Putida

    Directory of Open Access Journals (Sweden)

    Harikrishna Yadav Nanganuru

    2012-07-01

    Full Text Available Rhamnolipid as a potent natural biosurfactant has a wide range of potential applications, including enhanced oil recovery, biodegradation, and bioremediation. Observation of tensio-active indicated that biosurfactants were produced by the newly isolated and promising strain Pseudomonas putida. The biosurfactants were identified as rhamnolipids, the amphiphilic surface-active glycolipids usually secreted by Pseudomonas sp. In addition, the ability to generate rhamnolipids by placement of the right microbes might help overcome rhamnolipid adsorption during flow through reservoir rocks and the resultant degradation that would decrease the rhamnolipid concentrations. Their production was observed when the strain was grown on soluble substrates, such as glucose or on poorly soluble substrates. Maximum value 1.13 mg/ ml was occurred on the second day. Production of biosurfactants depends on the nutrient media. The surface tension was decreased with increasing time and growth.

  11. Identification and transcriptional profiling of Pseudomonas putida genes involved in furoic acid metabolism

    Science.gov (United States)

    Furfural (2-furaldehyde) is a furan formed by dehydration of pentose sugars. Pseudomonas putida Fu1 metabolizes furfural through a pathway involving conversion to 2-oxoglutarate, via 2-furoic acid and Coenzyme A intermediates. To identify genes involved in furan metabolism, two P. putida transposo...

  12. KPC-2-Producing Enterobacter cloacae and Pseudomonas putida Coinfection in a Liver Transplant Recipient▿

    OpenAIRE

    Jason W Bennett; Herrera, Monica L.; Lewis, James S.; Wickes, Brian W.; James H Jorgensen

    2008-01-01

    Carbapenemases are among the newest resistance mechanisms to emerge in some gram-negative bacteria. We describe bacteremia in a critically ill liver transplant recipient infected with KPC-2-producing Enterobacter cloacae and Pseudomonas putida. Although this enzyme has been previously described in Enterobacter spp., this is the first report of KPC carbapenemase in P. putida.

  13. Pseudomonas fluorescens and Pseudomonas putida for Promoting Growth of Jatropha curcas Seedling Root

    OpenAIRE

    Sri Sumarsih; Darban Haryanto

    2012-01-01

    Pseudomonas fluorescens and P. putida are Plant Growth Promoting Rhizobacteria (PGPR) that can produce growth hormone. The objective of this study is to know the effects of those two combined species of PGPR on seedling root growth of Jatropha curcas. The condition of the seedling root determines the success of dry land cultivation. The root which has wider coverage, is larger in number, and is bigger in diameter makes seedling more resistant to stress in dry land environment. In the experime...

  14. Investigation of plasmid-induced growth defect in Pseudomonas putida.

    Science.gov (United States)

    Mi, Jia; Sydow, Anne; Schempp, Florence; Becher, Daniela; Schewe, Hendrik; Schrader, Jens; Buchhaupt, Markus

    2016-08-10

    Genetic engineering in bacteria mainly relies on the use of plasmids. But despite their pervasive use for physiological studies as well as for the design and optimization of industrially used production strains, only limited information about plasmid induced growth defects is available for different replicons and organisms. Here, we present the identification and characterization of such a phenomenon for Pseudomonas putida transformants carrying the pBBR1-derived plasmid pMiS1. We identified the kanamycin resistance gene and the transcription factor encoding rhaR gene to be causal for the growth defect in P. putida. In contrast, this effect was not observed in Escherichia coli. The plasmid-induced growth defect was eliminated after introduction of a mutation in the plasmid-encoded rep gene, thus enabling construction of the non-toxic variant pMiS4. GFP reporters construct analyses and qPCR experiments revealed a distinctly lowered plasmid copy number for pMiS4, which is probably the reason for alleviation of the growth defect by this mutation. Our work expands the knowledge about plasmid-induced growth defects and provides a useful low-copy pBBR1 replicon variant. PMID:27287537

  15. Biofilm formation-defective mutants in Pseudomonas putida.

    Science.gov (United States)

    López-Sánchez, Aroa; Leal-Morales, Antonio; Jiménez-Díaz, Lorena; Platero, Ana I; Bardallo-Pérez, Juan; Díaz-Romero, Alberto; Acemel, Rafael D; Illán, Juan M; Jiménez-López, Julia; Govantes, Fernando

    2016-07-01

    Out of 8000 candidates from a genetic screening for Pseudomonas putida KT2442 mutants showing defects in biofilm formation, 40 independent mutants with diminished levels of biofilm were analyzed. Most of these mutants carried insertions in genes of the lap cluster, whose products are responsible for synthesis, export and degradation of the adhesin LapA. All mutants in this class were strongly defective in biofilm formation. Mutants in the flagellar regulatory genes fleQ and flhF showed similar defects to that of the lap mutants. On the contrary, transposon insertions in the flagellar structural genes fliP and flgG, that also impair flagellar motility, had a modest defect in biofilm formation. A mutation in gacS, encoding the sensor element of the GacS/GacA two-component system, also had a moderate effect on biofilm formation. Additional insertions targeted genes involved in cell envelope function: PP3222, encoding the permease element of an ABC-type transporter and tolB, encoding the periplasmic component of the Tol-OprL system required for outer membrane stability. Our results underscore the central role of LapA, suggest cross-regulation between motility and adhesion functions and provide insights on the role of cell envelope trafficking and maintenance for biofilm development in P. putida. PMID:27190143

  16. Transcriptome Dynamics of Pseudomonas putida KT2440 under Water Stress

    DEFF Research Database (Denmark)

    Gülez, Gamze; Dechesne, Arnaud; Workman, Christopher;

    2012-01-01

    Water deprivation can be a major stressor to microbial life in surface and subsurface soil. In unsaturated soils, the matric potential (Ψm) is often the main component of the water potential, which measures the thermodynamic availability of water. A low matric potential usually translates into...... water forming thin liquid films in the soil pores. Little is known of how bacteria respond to such conditions, where, in addition to facing water deprivation that might impair their metabolism, they have to adapt their dispersal strategy as swimming motility may be compromised. Using the pressurized...... porous surface model (PPSM), which allows creation of thin liquid films by controlling Ψm, we examined the transcriptome dynamics of Pseudomonas putida KT2440. We identified the differentially expressed genes in cells exposed to a mild matric stress (–0.4 MPa) for 4, 24, or 72 h. The major response was...

  17. Carbon Source Influences Population Heterogeneity In Pseudomonas Putida Kt2440 Biofilms

    DEFF Research Database (Denmark)

    Juel Christensen, Anne-Mette; Sternberg, Claus; Molin, Søren

    2015-01-01

    Introduction: Pseudomonas putida is well known as a potential cell factory for many different biochemicals. Biofilm-based production can be advantageous for possibly toxic products due to increased chemical tolerance and robustness. Biofilm cells frequently differentiate, which challenges the...

  18. Pseudomonas putida and Pseudomonas fluorescens Species Group Recovery from Human Homes Varies Seasonally and by Environment.

    Directory of Open Access Journals (Sweden)

    Susanna K Remold

    Full Text Available 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.

  19. The Identification and Validation of Novel Small Proteins in Pseudomonas Putida KT-2440

    DEFF Research Database (Denmark)

    Yang, Xiaochen; Long, Katherine

    2014-01-01

    activities and may lead to the discovery of novel antimicrobial agents. Our project focuses on the identification, validation and characterization of novel s-­‐proteins in the bacterium Pseudomonas putida KT-­2440. As there is virtually no information on s-­‐proteins in pseudomonads, the first step is to...... establish methods for the identification of short open reading frames (sORFs). A custom bioinformatics tool has been developed to predict sORFs from the genome and sRNA sequencing databases, where sequences containing a Shine-­Dalgarno (SD) sequence and start/stop codon are identified. In a second approach...

  20. Engineering Pseudomonas putida KT2440 for simultaneous degradation of organophosphates and pyrethroids and its application in bioremediation of soil.

    Science.gov (United States)

    Zuo, Zhenqiang; Gong, Ting; Che, You; Liu, Ruihua; Xu, Ping; Jiang, Hong; Qiao, Chuanling; Song, Cunjiang; Yang, Chao

    2015-06-01

    Agricultural soils are usually co-contaminated with organophosphate (OP) and pyrethroid pesticides. To develop a stable and marker-free Pseudomonas putida for co-expression of two pesticide-degrading enzymes, we constructed a suicide plasmid with expression cassettes containing a constitutive promoter J23119, an OP-degrading gene (mpd), a pyrethroid-hydrolyzing carboxylesterase gene (pytH) that utilizes the upp gene as a counter-selectable marker for upp-deficient P. putida. By introduction of suicide plasmid and two-step homologous recombination, both mpd and pytH genes were integrated into the chromosome of a robust soil bacterium P. putida KT2440 and no selection marker was left on chromosome. Functional expression of mpd and pytH in P. putida KT2440 was demonstrated by Western blot analysis and enzyme activity assays. Degradation experiments with liquid cultures showed that the mixed pesticides including methyl parathion, fenitrothion, chlorpyrifos, permethrin, fenpropathrin, and cypermethrin (0.2 mM each) were degraded completely within 48 h. The inoculation of engineered strain (10(6) cells/g) to soils treated with the above mixed pesticides resulted in a higher degradation rate than in noninoculated soils. All six pesticides could be degraded completely within 15 days in fumigated and nonfumigated soils with inoculation. Theses results highlight the potential of the engineered strain to be used for in situ bioremediation of soils co-contaminated with OP and pyrethroid pesticides. PMID:25917649

  1. Chromosomal Locus for Cadmium Resistance in Pseudomonas putida Consisting of a Cadmium-Transporting ATPase and a MerR Family Response Regulator

    OpenAIRE

    Lee, Seon-Woo; Glickmann, Eric; Cooksey, Donald A.

    2001-01-01

    Pseudomonads from environmental sources vary widely in their sensitivity to cadmium, but the basis for this resistance is largely uncharactarized. A chromosomal fragment encoding cadmium resistance was cloned from Pseudomonas putida 06909, a rhizosphere bacterium, and sequence analysis revealed two divergently transcribed genes, cadA and cadR. CadA was similar to cadmium-transporting ATPases known mostly from gram-positive bacteria, and to ZntA, a lead-, zinc-, and cadmium-transporting ATPase...

  2. Pseudomonas putida CSV86: a candidate genome for genetic bioaugmentation.

    Directory of Open Access Journals (Sweden)

    Vasundhara Paliwal

    Full Text Available Pseudomonas putida CSV86, a plasmid-free strain possessing capability to transfer the naphthalene degradation property, has been explored for its metabolic diversity through genome sequencing. The analysis of draft genome sequence of CSV86 (6.4 Mb revealed the presence of genes involved in the degradation of naphthalene, salicylate, benzoate, benzylalcohol, p-hydroxybenzoate, phenylacetate and p-hydroxyphenylacetate on the chromosome thus ensuring the stability of the catabolic potential. Moreover, genes involved in the metabolism of phenylpropanoid and homogentisate, as well as heavy metal resistance, were additionally identified. Ability to grow on vanillin, veratraldehyde and ferulic acid, detection of inducible homogentisate dioxygenase and growth on aromatic compounds in the presence of heavy metals like copper, cadmium, cobalt and arsenic confirm in silico observations reflecting the metabolic versatility. In silico analysis revealed the arrangement of genes in the order: tRNA(Gly, integrase followed by nah operon, supporting earlier hypothesis of existence of a genomic island (GI for naphthalene degradation. Deciphering the genomic architecture of CSV86 for aromatic degradation pathways and identification of elements responsible for horizontal gene transfer (HGT suggests that genetic bioaugmentation strategies could be planned using CSV86 for effective bioremediation.

  3. Cometabolic degradation kinetics of TCE and phenol by Pseudomonas putida.

    Science.gov (United States)

    Chen, Yan-Min; Lin, Tsair-Fuh; Huang, Chih; Lin, Jui-Che

    2008-08-01

    Modeling of cometabolic kinetics is important for better understanding of degradation reaction and in situ application of bio-remediation. In this study, a model incorporated cell growth and decay, loss of transformation activity, competitive inhibition between growth substrate and non-growth substrate and self-inhibition of non-growth substrate was proposed to simulate the degradation kinetics of phenol and trichloroethylene (TCE) by Pseudomonas putida. All the intrinsic parameters employed in this study were measured independently, and were then used for predicting the batch experimental data. The model predictions conformed well to the observed data at different phenol and TCE concentrations. At low TCE concentrations (6 mg l(-1)), only the model considering self-inhibition can describe the experimental data, suggesting that a self-inhibition of TCE was present in the system. The proposed model was also employed in predicting the experimental data conducted in a repeated batch reactor, and good agreements were observed between model predictions and experimental data. The results also indicated that the biomass loss in the degradation of TCE below 2 mg l(-1) can be totally recovered in the absence of TCE for the next cycle, and it could be used for the next batch experiment for the degradation of phenol and TCE. However, for higher concentration of TCE (>6 mg l(-1)), the recovery of biomass may not be as good as that at lower TCE concentrations. PMID:18586301

  4. Responses of KT2440 Pseudomonas putida to mild water stress

    DEFF Research Database (Denmark)

    Gülez, Gamze

    betydningen af flagellær motilitet og produktion af EPS under matric stess undersøgt ved brug af den såkaldte Porous Surface Model (PSM), som genererer væske-filmens effekter ved kontrol af !m. Det blev vist, at flagellær motilitet var begrænset under matric stress; Pseudomonas putida KT2440 kolonier udviste...... væsentlig højere vækstrater tæt ved mætningsbetingelser (-0.5 kPa !m) end kolonier dyrket under matric stress (ved -3.6 kPa !m). Desuden viste 1:1 kompettitive eksperimenter med begge phenotyper ved mættede betingelser, at den naturligt forekomne KT2440 udkonkurrerer dens ikke-flagellare mutant med hensyn...... til overflade-kolonivækst, hvorimod begge phenotyper sameksisterer under matric stress (-3.6 kPa). Denne afhandling har endvidere vist at bakterierne kunne drage fordel af pludseligt forekomne mættede betingelser (5 minutter, to gange dagligt) idet flagellær motilitet blev observeret. Dette resultat...

  5. Influence of putative exopolysaccharide genes on Pseudomonas putida KT2440 biofilm stability

    DEFF Research Database (Denmark)

    Nilsson, Martin; Chiang, Wen-Chi; Fazli, Mustafa;

    2011-01-01

    We report a study of the role of putative exopolysaccharide gene clusters in the formation and stability of Pseudomonas putida KT2440 biofilm. Two novel putative exopolysaccharide gene clusters, pea and peb, were identified, and evidence is provided that they encode products that stabilize P....... putida KT2440 biofilm. The gene clusters alg and bcs, which code for proteins mediating alginate and cellulose biosynthesis, were found to play minor roles in P. putida KT2440 biofilm formation and stability under the conditions tested. A P. putida KT2440 derivative devoid of any identifiable...... exopolysaccharide genes was found to form biofilm with a structure similar to wild-type biofilm, but with a stability lower than that of wild-type biofilm. Based on our data, we suggest that the formation of structured P. putida KT2440 biofilm can occur in the absence of exopolysaccharides; however...

  6. Antibiotic Resistance Determinants in a Pseudomonas putida Strain Isolated from a Hospital

    OpenAIRE

    Molina, Lázaro; Udaondo, Zulema; Duque, Estrella; Fernández, Matilde; Molina-Santiago, Carlos; Roca, Amalia; Porcel, Mario; de la Torre, Jesús; Segura, Ana; Plesiat, Patrick; Jeannot, Katy; Ramos, Juan-Luis

    2014-01-01

    Environmental microbes harbor an enormous pool of antibiotic and biocide resistance genes that can impact the resistance profiles of animal and human pathogens via horizontal gene transfer. Pseudomonas putida strains are ubiquitous in soil and water but have been seldom isolated from humans. We have established a collection of P. putida strains isolated from in-patients in different hospitals in France. One of the isolated strains (HB3267) kills insects and is resistant to the majority of the...

  7. Transcriptome dynamics of Pseudomonas putida KT2440 under water stress.

    Science.gov (United States)

    Gülez, Gamze; Dechesne, Arnaud; Workman, Christopher T; Smets, Barth F

    2012-02-01

    Water deprivation can be a major stressor to microbial life in surface and subsurface soil. In unsaturated soils, the matric potential (Ψ(m)) is often the main component of the water potential, which measures the thermodynamic availability of water. A low matric potential usually translates into water forming thin liquid films in the soil pores. Little is known of how bacteria respond to such conditions, where, in addition to facing water deprivation that might impair their metabolism, they have to adapt their dispersal strategy as swimming motility may be compromised. Using the pressurized porous surface model (PPSM), which allows creation of thin liquid films by controlling Ψ(m), we examined the transcriptome dynamics of Pseudomonas putida KT2440. We identified the differentially expressed genes in cells exposed to a mild matric stress (-0.4 MPa) for 4, 24, or 72 h. The major response was detected at 4 h before gradually disappearing. Upregulation of alginate genes was notable in this early response. Flagellar genes were not downregulated, and the microarray data even suggested increasing expression as the stress prolonged. Moreover, we tested the effect of polyethylene glycol 8000 (PEG 8000), a nonpermeating solute often used to simulate Ψ(m), on the gene expression profile and detected a different profile than that observed by directly imposing Ψ(m). This study is the first transcriptome profiling of KT2440 under directly controlled Ψ(m) and also the first to show the difference in gene expression profiles between a PEG 8000-simulated and a directly controlled Ψ(m). PMID:22138988

  8. Bioconversion of styrene to poly(hydroxyalkanoate) (PHA) by the new bacterial strain Pseudomonas putida NBUS12.

    Science.gov (United States)

    Tan, Giin-Yu Amy; Chen, Chia-Lung; Ge, Liya; Li, Ling; Tan, Swee Ngin; Wang, Jing-Yuan

    2015-01-01

    Styrene is a toxic pollutant commonly found in waste effluents from plastic processing industries. We herein identified and characterized microorganisms for bioconversion of the organic eco-pollutant styrene into a valuable biopolymer medium-chain-length poly(hydroxyalkanoate) (mcl-PHA). Twelve newly-isolated styrene-degrading Pseudomonads were obtained and partial phaC genes were detected by PCR in these isolates. These isolates assimilated styrene to produce mcl-PHA, forming PHA contents between 0.05±0.00 and 23.10±3.25% cell dry mass (% CDM). The best-performing isolate was identified as Pseudomonas putida NBUS12. A genetic analysis of 16S rDNA and phaZ genes revealed P. putida NBUS12 as a genetically-distinct strain from existing phenotypically-similar bacterial strains. This bacterium achieved a final biomass of 1.28±0.10 g L(-1) and PHA content of 32.49±2.40% CDM. The extracted polymer was mainly comprised of 3-hydroxyhexanoate (C6 ), 3-hydroxyoctanoate (C8 ), 3-hydroxydecanoate (C10 ), 3-hydroxydodecanoate (C12 ), and 3-hydroxytetradecanoate (C14 ) monomers at a ratio of 2:42:1257:17:1. These results collectively suggested that P. putida NBUS12 is a promising candidate for the biotechnological conversion of styrene into mcl-PHA. PMID:25740622

  9. Acute toxic effects of three pesticides on Pseudomonas putida monitored by microcalorimeter.

    Science.gov (United States)

    Chen, Hui-Lun; Yao, Jun; Wang, Fei; Bramanti, Emilia; Maskow, Thomas; Zaray, Gyula

    2009-02-01

    A series of calorimetric experiments were performed to investigate the toxic effects of beta-cypermethrin (BCP), bensulfuron-methyl (BSM) and prometryne (PM) on Pseudomonas putida (P. putida). The metabolic action of P. putida on the three pesticides was studied by obtaining power-time curves. The growth of P. putida was inhibited completely in each case when the concentrations of pesticides were up to 80 micro g mL(- 1). The relationships between the inhibitory ratio (k) and doses of contaminants were approximately linear for the three pesticides. The total heat dissipated per milliliter (Q(total)) for the pesticides decreased during the course of the experiment. The OD(600) of P. putida growth in the absence and presence of pesticides was also obtained. The power-time curves of P. putida growth coincided with its turbidity curves. This elucidates that microcalorimetric method agrees well with the routine microbiological method. Among these three pesticides, BSM was found to be the most toxic with an IC(50) of 19.24 micro g mL(- 1) against P. putida. PM exhibited moderate virulence with an IC(50) of 27.86 micro g mL(- 1) and BCP had the lowest toxicity with an IC(50) of 39.64 micro g mL(- 1). PMID:19130374

  10. Decolorization of industrial synthetic dyes using engineered Pseudomonas putida cells with surface-immobilized bacterial laccase

    Directory of Open Access Journals (Sweden)

    Wang Wei

    2012-06-01

    Full Text Available Abstract Background Microbial laccases are highly useful in textile effluent dye biodegradation. However, the bioavailability of cellularly expressed or purified laccases in continuous operations is usually limited by mass transfer impediment or enzyme regeneration difficulty. Therefore, this study develops a regenerable bacterial surface-displaying system for industrial synthetic dye decolorization, and evaluates its effects on independent and continuous operations. Results A bacterial laccase (WlacD was engineered onto the cell surface of the solvent-tolerant bacterium Pseudomonas putida to construct a whole-cell biocatalyst. Ice nucleation protein (InaQ anchor was employed, and the ability of 1 to 3 tandemly aligned N-terminal repeats to direct WlacD display were compared. Immobilized WlacD was determined to be surface-displayed in functional form using Western blot analysis, immunofluorescence microscopy, flow cytometry, and whole-cell enzymatic activity assay. Engineered P. putida cells were then applied to decolorize the anthraquinone dye Acid Green (AG 25 and diazo-dye Acid Red (AR 18. The results showed that decolorization of both dyes is Cu2+- and mediator-independent, with an optimum temperature of 35°C and pH of 3.0, and can be stably performed across a temperature range of 15°C to 45°C. A high activity toward AG25 (1 g/l with relative decolorization values of 91.2% (3 h and 97.1% (18 h, as well as high activity to AR18 (1 g/l by 80.5% (3 h and 89.0% (18 h, was recorded. The engineered system exhibited a comparably high activity compared with those of separate dyes in a continuous three-round shake-flask decolorization of AG25/AR18 mixed dye (each 1 g/l. No significant decline in decolorization efficacy was noted during first two-rounds but reaction equilibriums were elongated, and the residual laccase activity eventually decreased to low levels. However, the decolorizing capacity of the system was easily retrieved

  11. Survival and impact of genetically engineered Pseudomonas putida harboring mercury resistance gene in soil microcosms.

    Science.gov (United States)

    Iwasaki, K; Uchiyama, H; Yagi, O

    1994-01-01

    The survival of genetically engineered and wild-type Pseudomonas putida PpY101, that contained a recombinant plasmid pSR134 conferring mercury resistance, were monitored in andosol and sand microcosms. The survival of genetically engineered and wild-type P. putida was not significantly different in andosol. The population change of the two strains was dissimilar in andosol and sand. The survival of genetically engineered and wild-type P. putida strains was affected by the water content of andosol, and increased with the increment of the water content. The impact of the addition of genetically engineered and wild-type P. putida strains on indigenous bacteria and fungi was examined. Inoculation of both strains had no apparent effect on the density of indigenous microorganisms. PMID:7764510

  12. Characterization of cell lysis in Pseudomonas putida induced upon expression of heterologous killing genes

    DEFF Research Database (Denmark)

    Ronchel, M.C.; Molina, L.; Witte, A.; Lutbiz, W.; Molin, Søren; Ramos, J.L.; Rodriguez, Cayo Juan Ramos

    1998-01-01

    Active biological containment systems are based on the controlled expression of killing genes. These systems are of interest for the Pseudomonadaceae because of the potential applications of these microbes as bioremediation agents and biopesticides, The physiological effects that lead to cell death...... upon the induction of expression of two different heterologous killing genes in nonpathogenic Pseudomonas putida KT2440 derivatives have been analyzed, P. putida CMC4 and CMC12 carry in their chromosomes a fusion of the PAl-04/03 promoter to the Escherichia coli gef gene and the phi X174 lysis gene E......, respectively. Expression of the killing genes is controlled by the LacI protein, whose expression is initiated from the XylS-dependent Pm promoter. Under induced conditions, killing of P. putida CMC12 cells mediated by phi X174 lysis protein E was faster than that observed for P. putida CMC4, for which the Gef...

  13. Electricity Generation and Wastewater Treatment of Oil Refinery in Microbial Fuel Cells Using Pseudomonas putida

    Directory of Open Access Journals (Sweden)

    Dip Majumder

    2014-09-01

    Full Text Available Microbial fuel cells (MFCs represent a novel platform for treating wastewater and at the same time generating electricity. Using Pseudomonas putida (BCRC 1059, a wild-type bacterium, we demonstrated that the refinery wastewater could be treated and also generate electric current in an air-cathode chamber over four-batch cycles for 63 cumulative days. Our study indicated that the oil refinery wastewater containing 2213 mg/L (ppm chemical oxygen demand (COD could be used as a substrate for electricity generation in the reactor of the MFC. A maximum voltage of 355 mV was obtained with the highest power density of 0.005 mW/cm2 in the third cycle with a maximum current density of 0.015 mA/cm2 in regard to the external resistor of 1000 Ω. A maximum coulombic efficiency of 6 × 10−2% was obtained in the fourth cycle. The removal efficiency of the COD reached 30% as a function of time. Electron transfer mechanism was studied using cyclic voltammetry, which indicated the presence of a soluble electron shuttle in the reactor. Our study demonstrated that oil refinery wastewater could be used as a substrate for electricity generation.

  14. Functional analysis of aromatic biosynthetic pathways in Pseudomonas putida KT2440.

    Science.gov (United States)

    Molina-Henares, M Antonia; García-Salamanca, Adela; Molina-Henares, A Jesús; de la Torre, Jesús; Herrera, M Carmen; Ramos, Juan L; Duque, Estrella

    2009-01-01

    Pseudomonas putida KT2440 is a non-pathogenic prototrophic bacterium with high potential for biotechnological applications. Despite all that is known about this strain, the biosynthesis of essential chemicals has not been fully analysed and auxotroph mutants are scarce. We carried out massive mini-Tn5 random mutagenesis and screened for auxotrophs that require aromatic amino acids. The biosynthesis of aromatic amino acids was analysed in detail including physical and transcriptional organization of genes, complementation assays and feeding experiments to establish pathway intermediates. There is a single pathway from chorismate leading to the biosynthesis of tryptophan, whereas the biosynthesis of phenylalanine and tyrosine is achieved through multiple convergent pathways. Genes for tryptophan biosynthesis are grouped in unlinked regions with the trpBA and trpGDE genes organized as operons and the trpI, trpE and trpF genes organized as single transcriptional units. The pheA and tyrA gene-encoding multifunctional enzymes for phenylalanine and tyrosine biosynthesis are linked in the chromosome and form an operon with the serC gene involved in serine biosynthesis. The last step in the biosynthesis of these two amino acids requires an amino transferase activity for which multiple tyrB-like genes are present in the host chromosome. PMID:21261884

  15. Complete biodegradation of chlorpyrifos by engineered Pseudomonas putida cells expressing surface-immobilized laccases.

    Science.gov (United States)

    Liu, Jin; Tan, Luming; Wang, Jing; Wang, Zhiyong; Ni, Hong; Li, Lin

    2016-08-01

    The long-term abuse use of chlorpyrifos-like pesticides in agriculture and horticulture has resulted in significant soil or water contamination and a worldwide ecosystem threat. In this study, the ability of a solvent-tolerant bacterium, Pseudomonas putida MB285, with surface-displayed bacterial laccase, to biodegrade chlorpyrifos was investigated. The results of compositional analyses of the degraded products demonstrate that the engineered MB285 was capable of completely eliminating chlorpyrifos via direct biodegradation, as determined by high-performance liquid chromatography and gas chromatography-mass spectrometry assays. Two intermediate metabolites, namely 3,5,6-trichloro-2-pyridinol (TCP) and diethyl phosphate, were temporarily detectable, verifying the joint and stepwise degradation of chlorpyrifos by surface laccases and certain cellular enzymes, whereas the purified free laccase incompletely degraded chlorpyrifos into TCP. The degradation reaction can be conducted over a wide range of pH values (2-7) and temperatures (5-55 °C) without the need for Cu(2+). Bioassays using Caenorhabditis elegans as an indicator organism demonstrated that the medium was completely detoxified of chlorpyrifos by degradation. Moreover, the engineered cells exhibited a high capacity of repeated degradation and good performance in continuous degradation cycles, as well as a high capacity to degrade real effluents containing chlorpyrifos. Therefore, the developed system exhibited a high degradation capacity and performance and constitutes an improved approach to address chlorpyrifos contamination in chlorpyrifos-remediation practice. PMID:27231878

  16. A substrate dependent biological containment systems for Pseudomonas putida based on the Escherichia coli gef gene

    DEFF Research Database (Denmark)

    Jensen, Lars Bogø; Ramos, J. L.; Kaneva, Z.; Molin, Søren

    1993-01-01

    A model substrate-dependent suicide system to biologically contain Pseudomonas putida KT2440 is reported. The system consists of two elements. One element carries a fusion between a synthetic lac promoter (PA1-04/03) and the gef gene, which encodes a killing function. This element is contained...... within a transposaseless mini-Tn5 transposon so that it can be integrated at random locations on the Pseudomonas chromosome. The second element, harbored by plasmid pCC102, is designed to control the first and bears a fusion between the promoter of the P. putida TOL plasmid-encoded meta-cleavage pathway...... operon (Pm) and the lacI gene, encoding the Lac repressor, plus xylS2, coding for a positive regulator of Pm. In liquid culture under optimal growth conditions and in sterile and nonsterile soil microcosms, P. putida KT2440 (pWWO) bearing the containment system behaves as designed. In the presence of a...

  17. Marine Pseudomonas putida: a potential source of antimicrobial substances against antibiotic-resistant bacteria

    Directory of Open Access Journals (Sweden)

    Palloma Rodrigues Marinho

    2009-08-01

    Full Text Available Bacteria isolated from marine sponges found off the coast of Rio de Janeiro, Brazil, were screened for the production of antimicrobial substances. We report a new Pseudomonas putida strain (designated P. putida Mm3 isolated from the sponge Mycale microsigmatosa that produces a powerful antimicrobial substance active against multidrug-resistant bacteria. P. putida Mm3 was identified on the basis of 16S rRNA gene sequencing and phenotypic tests. Molecular typing for Mm3 was performed by RAPD-PCR and comparison of the results to other Pseudomonas strains. Our results contribute to the search for new antimicrobial agents, an important strategy for developing alternative therapies to treat infections caused by multidrug-resistant bacteria.

  18. Integrated foam fractionation for heterologous rhamnolipid production with recombinant Pseudomonas putida in a bioreactor

    OpenAIRE

    Beuker, Janina; Steier, Anke; Wittgens, Andreas; Rosenau, Frank; Henkel, Marius; Hausmann, Rudolf

    2016-01-01

    Heterologeous production of rhamnolipids in Pseudomonas putida is characterized by advantages of a non-pathogenic host and avoidance of the native quorum sensing regulation in Pseudomonas aeruginosa. Yet, downstream processing is a major problem in rhamnolipid production and increases in complexity at low rhamnolipid titers and when using chemical foam control. This leaves the necessity of a simple concentrating and purification method. Foam fractionation is an elegant method for in situ prod...

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

    OpenAIRE

    Matilla, Miguel A.; Pizarro-Tobias, Paloma; Roca, Amalia; Fernández, Matilde; Duque, Estrella; Molina, Lázaro; WU, XIAO; van der Lelie, Daniel; Gómez, Manuel J.; Segura, Ana; Ramos, Juan-Luis

    2010-01-01

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  1. Interaction of Pseudomonas putida ATCC 12633 and Bacteriophage gh-1 in Berea Sandstone Rock

    OpenAIRE

    Chang, Philip Lee; Yen, Teh Fu

    1985-01-01

    Measurements of the passage of Pseudomonas putida ATCC 12633 and a phage-resistant mutant through Berea sandstone rock were made. When bacteriophage gh-1 was adsorbed within the rock matrix, a reduction in the passage of the susceptible but not the resistant cells through the rock was observed.

  2. Interaction of Pseudomonas putida ATCC 12633 and Bacteriophage gh-1 in Berea Sandstone Rock.

    Science.gov (United States)

    Chang, P L; Yen, T F

    1985-12-01

    Measurements of the passage of Pseudomonas putida ATCC 12633 and a phage-resistant mutant through Berea sandstone rock were made. When bacteriophage gh-1 was adsorbed within the rock matrix, a reduction in the passage of the susceptible but not the resistant cells through the rock was observed. PMID:16346956

  3. Construction of an efficient biologically contained Pseudomonas putida strain and its survival in outdoor assays

    DEFF Research Database (Denmark)

    Molina, Lazaro; Rodriguez, Cayo Juan Ramos; Ronchel, Maria C.; Molin, Søren; Ramos, Juan L.

    1998-01-01

    fusion of the Pm promoter to the lad gene plus the positive regulator of the Pm promoter, the xylS gene. This mini-Tn5 transposon was transferred to the chromosome of Pseudomonas putida CMC4, and in culture this strain survived in the presence of 3-methylbenzoate (an XylS effector) and committed suicide...

  4. Using "Pseudomonas Putida xylE" Gene to Teach Molecular Cloning Techniques for Undergraduates

    Science.gov (United States)

    Dong, Xu; Xin, Yi; Ye, Li; Ma, Yufang

    2009-01-01

    We have developed and implemented a serial experiment in molecular cloning laboratory course for undergraduate students majored in biotechnology. "Pseudomonas putida xylE" gene, encoding catechol 2, 3-dioxygenase, was manipulated to learn molecular biology techniques. The integration of cloning, expression, and enzyme assay gave students a chance…

  5. Functional, genetic and chemical characterization of biosurfactants produced by plant growth-promoting Pseudomonas putida 267

    NARCIS (Netherlands)

    Kruijt, M.; Tran, H.; Raaijmakers, J.M.

    2009-01-01

    Aims: Plant growth-promoting Pseudomonas putida strain 267, originally isolated from the rhizosphere of black pepper, produces biosurfactants that cause lysis of zoospores of the oomycete pathogen Phytophthora capsici. The biosurfactants were characterized, the biosynthesis gene(s) partially identif

  6. Investigation Of The Primary Transcriptome Of The Production Organism Pseudomonas Putida

    DEFF Research Database (Denmark)

    D'Arrigo, Isotta; Bojanovic, Klara; Long, Katherine

    2015-01-01

    compounds, a capability that renders the bacterium useful in bioremediation. Finally, P. putida shows a high potential as a cell factory for the production of several compounds. Methods: Here, a differential RNA-sequencing approach (dRNA-seq) is used to gain new insights into the organization of the P...

  7. Benzene, toluene and xylene biodegradation by Pseudomonas putida CCMI 852 Biodegradação de benzeno, tolueno e xileno pela Pseudomonas putida CCMI 852

    Directory of Open Access Journals (Sweden)

    Marcelo Henrique Otenio

    2005-09-01

    Full Text Available A minimal liquid medium containing benzene (B, toluene (T and xylene (X and mixtures thereof, was used to evaluate degradation activity of Pseudomonas putida CCMI 852 containing a TOL plasmid. Experiments were developed with B, T and X (100 mg L-1, with mixtures of BT, BX, and TX (50 + 50 mg L-1 each and BTX (33.3 + 33.3 + 33.3 mg L-1 each, added to 500 mL of medium. After 18 to 24 hours, the inoculum was added and solvent disappearance was determined after 24 to 25 hours by GC. Results showed that P. putida CCMI 852 was able to metabolize T and X, but B was not metabolized. In a BTX mixture, B was not metabolized and T and X degradation rate decreased 50%.Meio mineral líquido contendo benzeno (B ou tolueno (T ou xileno (X a 100 mg L-1 e suas misturas de BT, BX e TX (50 + 50 mg L-1 cada mistura e BTX (33,3 + 33,3 + 33,3 mg L-1 cada mistura foram utilizados para avaliar a atividade de degradação de B, T e X por Pseudomonas putida CCMI 852 contendo um plasmídeo TOL. Após 18 a 24 horas de homogenização da mistura, o inoculo foi adicionado e o decréscimo da concentração dos solventes foi determinado entre 24 e 25 horas por GC. Pseudomonas putida CCMI 852 foi capaz de metabolizar T e X, mas não B. Na mistura BTX, B não foi metabolizado também e a velocidade de degradação de T e X decresceu cerca de 50% comparado com soluções contendo apenas T ou X.

  8. DETECTION OF PHENOL DEGRADING BACTERIA AND PSEUDOMONAS PUTIDA IN ACTIVATED SLUDGE BY POLYMERASE CHAIN REACTION

    Directory of Open Access Journals (Sweden)

    H. Movahedyan ، H. Khorsandi ، R. Salehi ، M. Nikaeen

    2009-04-01

    Full Text Available Phenol is one of the organic pollutants in various industrial wastewaters especially petrochemical and oil refining. Biological treatment is one of the considerable choices for removing of phenol present in these wastewaters. Identification of effective microbial species is considered as one of the important priorities for production of the biomass in order to achieve desirable kinetic of biological reactions. Basic purpose of this research is identification of phenol-degrading Pseudomonas Putida in activated sludge by polymerase chain reaction (PCR that has high speed and specificity. In this research, 10 various colonies of phenol-degrading bacteria were isolated from municipal activated sludge and the rate of phenol removal and growth rate of these bacteria were assessed in different concentrations of phenol (200 – 900 mg/L. Confirmation of the largest subunit of multicomponent phenol hydroxylase (LmPH gene and gene coding the N fragment in Pseudomonas Putida-derived methyl phenol operon (DmpN gene through PCR were used for general identification of phenol-degrading bacteria and Pseudomonas Putida, respectively. Presence of a 600 bp (base pairs bond in all of isolated strains indicated that they contain phenol hydroxylase gene. 6 of 10 isolated bacteria were Pseudomonas Putida because they produced a 199 bp PCR product by DmpN primers. According to PCR results in this study, the best phenol-degrading bacteria that can utilize 500 – 600 mg/L phenol completely after 48 hours incubation, belong to Pseudomonas Putida strains. It is clear that use of isolated bacteria can lead to considerable decrease of treatment time as well as promotion of phenol removal rate.

  9. In situ biosurfactant production and hydrocarbon removal by Pseudomonas putida CB-100 in bioaugmented and biostimulated oil-contaminated soil

    OpenAIRE

    Martínez-Toledo Ángeles; Rodríguez-Vázquez Refugio

    2013-01-01

    In situ biosurfactant (rhamnolipid) production by Pseudomonas putida CB-100 was achieved during a bioaugmented and biostimulated treatment to remove hydrocarbons from aged contaminated soil from oil well drilling operations. Rhamnolipid production and contaminant removal were determined for several treatments of irradiated and non-irradiated soils: nutrient addition (nitrogen and phosphorus), P. putida addition, and addition of both (P. putida and nutrients). The results were compared against...

  10. Manganese (Mn oxidation increases intracellular Mn in Pseudomonas putida GB-1.

    Directory of Open Access Journals (Sweden)

    Andy Banh

    Full Text Available Bacterial manganese (Mn oxidation plays an important role in the global biogeochemical cycling of Mn and other compounds, and the diversity and prevalence of Mn oxidizers have been well established. Despite many hypotheses of why these bacteria may oxidize Mn, the physiological reasons remain elusive. Intracellular Mn levels were determined for Pseudomonas putida GB-1 grown in the presence or absence of Mn by inductively coupled plasma mass spectrometry (ICP-MS. Mn oxidizing wild type P. putida GB-1 had higher intracellular Mn than non Mn oxidizing mutants grown under the same conditions. P. putida GB-1 had a 5 fold increase in intracellular Mn compared to the non Mn oxidizing mutant P. putida GB-1-007 and a 59 fold increase in intracellular Mn compared to P. putida GB-1 ∆2665 ∆2447. The intracellular Mn is primarily associated with the less than 3 kDa fraction, suggesting it is not bound to protein. Protein oxidation levels in Mn oxidizing and non oxidizing cultures were relatively similar, yet Mn oxidation did increase survival of P. putida GB-1 when oxidatively stressed. This study is the first to link Mn oxidation to Mn homeostasis and oxidative stress protection.

  11. PSEUDOMONAS-PUTIDA KT2442 CULTIVATED ON GLUCOSE ACCUMULATES POLY(3-HYDROXYALKANOATES) CONSISTING OF SATURATED AND UNSATURATED MONOMERS

    NARCIS (Netherlands)

    HUIJBERTS, GNM; EGGINK, G; DEWAARD, P; HUISMAN, GW; WITHOLT, B

    1992-01-01

    The biosynthesis of poly(3-hydroxyalkanoates) (PHAs) by Pseudomonas putida KT2442 during growth on carbohydrates was studied. PHAs isolated from P. putida cultivated on glucose, fructose, and glycerol were found to have a very similar monomer composition. In addition to the major constituent 3-hydro

  12. A study of the growth of Pseudomonas putida CP1 on mono-chlorophenols

    OpenAIRE

    Fakhruddin, A. N. M.

    2003-01-01

    Pseudomonas putida CPI grew on all three mono-chlorophenol isomers when supplied as the sole source of carbon and energy. The biodegradability of the mono-chlorophenols followed the order: 4-chlorophenol > 2-chlorophenol > 3-chlorophenol. P. putida CPI was able to degrade 300 ppm 4-chlorophenol, 250 ppm 2-chlorophenol and 200 ppm of 3-chlorophenol. In the presence of fructose (1%, w/v) the organism could degrade 400 ppm 4-chlorophenol, 500 ppm 2-chlorophenol and 300 ppm 3-chlorophenol. Ch...

  13. A substrate dependent biological containment systems for Pseudomonas putida based on the Escherichia coli gef gene

    DEFF Research Database (Denmark)

    Jensen, Lars Bogø; Ramos, J. L.; Kaneva, Z.;

    1993-01-01

    operon (Pm) and the lacI gene, encoding the Lac repressor, plus xylS2, coding for a positive regulator of Pm. In liquid culture under optimal growth conditions and in sterile and nonsterile soil microcosms, P. putida KT2440 (pWWO) bearing the containment system behaves as designed. In the presence of a......A model substrate-dependent suicide system to biologically contain Pseudomonas putida KT2440 is reported. The system consists of two elements. One element carries a fusion between a synthetic lac promoter (PA1-04/03) and the gef gene, which encodes a killing function. This element is contained...

  14. Novel system for recognizing and eliminating foreign DNA in Pseudomonas putida.

    OpenAIRE

    Kim, K.; Meyer, R J

    1984-01-01

    Derivatives of pQSR49 (R1162::Tn1) containing cloned fragments of Escherichia coli chromosomal DNA are stable in E. coli but unstable in Pseudomonas putida. Similar derivatives containing P. putida chromosomal DNA are stable in both species. Instability is a consequence of plasmid loss during growth and is not due to death or inhibition of growth of plasmid-containing cells. Average copy numbers per cell of the unstable hybrid plasmids are similar to that of pQSR49, indicating that instabilit...

  15. Systemic resistance and lipoxygenase-related defence response induced in tomato by Pseudomonas putida strain BTP1

    Directory of Open Access Journals (Sweden)

    Dommes Jacques

    2008-11-01

    Full Text Available Abstract Background Previous studies showed the ability of Pseudomonas putida strain BTP1 to promote induced systemic resistance (ISR in different host plants. Since ISR is long-lasting and not conducive for development of resistance of the targeted pathogen, this phenomenon can take part of disease control strategies. However, in spite of the numerous examples of ISR induced by PGPR in plants, only a few biochemical studies have associated the protective effect with specific host metabolic changes. Results In this study, we showed the protective effect of this bacterium in tomato against Botrytis cinerea. Following treatment by P. putida BTP1, analyses of acid-hydrolyzed leaf extracts showed an accumulation of antifungal material after pathogen infection. The fungitoxic compounds thus mainly accumulate as conjugates from which active aglycones may be liberated through the activity of hydrolytic enzymes. These results suggest that strain BTP1 can elicit systemic phytoalexin accumulation in tomato as one defence mechanism. On another hand, we have shown that key enzymes of the lipoxygenase pathway are stimulated in plants treated with the bacteria as compared with control plants. Interestingly, this stimulation is observed only after pathogen challenge in agreement with the priming concept almost invariably associated with the ISR phenomenon. Conclusion Through the demonstration of phytoalexin accumulation and LOX pathway stimulation in tomato, this work provides new insights into the diversity of defence mechanisms that are inducible by non-pathogenic bacteria in the context of ISR.

  16. Toxicity of graphene oxide on growth and metabolism of Pseudomonas putida.

    Science.gov (United States)

    Combarros, R G; Collado, S; Díaz, M

    2016-06-01

    The increasing consumption of graphene derivatives leads to greater presence of these materials in wastewater treatment plants and ecological systems. The toxicity effect of graphene oxide (GO) on the microbial functions involved in the biological wastewater treatment process is studied, using Pseudomonas putida and salicylic acid (SA) as bacterial and pollutant models. A multiparametric flow cytometry (FC) method has been developed to measure the metabolic activity and viability of P. putida in contact with GO. A continuous reduction in the percentages of viable cells and a slight increase, lower than 5%, in the percentages of damaged and dead cells, suggest that P. putida in contact with GO loses the membrane integrity but preserves metabolic activity. The growth of P. putida was strongly inhibited by GO, since 0.05mgmL(-1) of GO reduced the maximum growth by a third, and the inhibition was considerably greater for GO concentrations higher than 0.1mgmL(-1). The specific SA removal rate decreased with GO concentration up to 0.1mgmL(-1) indicating that while GO always reduces the growth of P. putida, for concentrations higher than 0.1mgmL(-1), it also reduces its activity. Similar behaviour is observed using simulated urban and industrial wastewaters, the observed effects being more acute in the industrial wastewaters. PMID:26937871

  17. Benzoxazinoids in root exudates of maize attract Pseudomonas putida to the rhizosphere.

    Directory of Open Access Journals (Sweden)

    Andrew L Neal

    Full Text Available Benzoxazinoids, such as 2,4-dihydroxy-7-methoxy-2H-1,4-benzoxazin-3(4H-one (DIMBOA, are secondary metabolites in grasses. In addition to their function in plant defence against pests and diseases above-ground, benzoxazinoids (BXs have also been implicated in defence below-ground, where they can exert allelochemical or antimicrobial activities. We have studied the impact of BXs on the interaction between maize and Pseudomonas putida KT2440, a competitive coloniser of the maize rhizosphere with plant-beneficial traits. Chromatographic analyses revealed that DIMBOA is the main BX compound in root exudates of maize. In vitro analysis of DIMBOA stability indicated that KT2440 tolerance of DIMBOA is based on metabolism-dependent breakdown of this BX compound. Transcriptome analysis of DIMBOA-exposed P. putida identified increased transcription of genes controlling benzoate catabolism and chemotaxis. Chemotaxis assays confirmed motility of P. putida towards DIMBOA. Moreover, colonisation essays in soil with Green Fluorescent Protein (GFP-expressing P. putida showed that DIMBOA-producing roots of wild-type maize attract significantly higher numbers of P. putida cells than roots of the DIMBOA-deficient bx1 mutant. Our results demonstrate a central role for DIMBOA as a below-ground semiochemical for recruitment of plant-beneficial rhizobacteria during the relatively young and vulnerable growth stages of maize.

  18. Protective role of glycerol against benzene stress: insights from the Pseudomonas putida proteome.

    Science.gov (United States)

    Bhaganna, Prashanth; Bielecka, Agata; Molinari, Gabriella; Hallsworth, John E

    2016-05-01

    Chemical activities of hydrophobic substances can determine the windows of environmental conditions over which microbial systems function and the metabolic inhibition of microorganisms by benzene and other hydrophobes can, paradoxically, be reduced by compounds that protect against cellular water stress (Bhaganna et al. in Microb Biotechnol 3:701-716, 2010; Cray et al. in Curr Opin Biotechnol 33:228-259, 2015a). We hypothesized that this protective effect operates at the macromolecule structure-function level and is facilitated, in part at least, by genome-mediated adaptations. Based on proteome profiling of the soil bacterium Pseudomonas putida, we present evidence that (1) benzene induces a chaotrope-stress response, whereas (2) cells cultured in media supplemented with benzene plus glycerol were protected against chaotrope stress. Chaotrope-stress response proteins, such as those involved in lipid and compatible-solute metabolism and removal of reactive oxygen species, were increased by up to 15-fold in benzene-stressed cells relative to those of control cultures (no benzene added). By contrast, cells grown in the presence of benzene + glycerol, even though the latter grew more slowly, exhibited only a weak chaotrope-stress response. These findings provide evidence to support the hypothesis that hydrophobic substances induce a chaotropicity-mediated water stress, that cells respond via genome-mediated adaptations, and that glycerol protects the cell's macromolecular systems. We discuss the possibility of using compatible solutes to mitigate hydrocarbon-induced stresses in lignocellulosic biofuel fermentations and for industrial and environmental applications. PMID:26612269

  19. Genome-scale reconstruction and analysis of the Pseudomonas putida KT2440 metabolic network facilitates applications in biotechnology.

    Directory of Open Access Journals (Sweden)

    Jacek Puchałka

    2008-10-01

    Full Text Available A cornerstone of biotechnology is the use of microorganisms for the efficient production of chemicals and the elimination of harmful waste. Pseudomonas putida is an archetype of such microbes due to its metabolic versatility, stress resistance, amenability to genetic modifications, and vast potential for environmental and industrial applications. To address both the elucidation of the metabolic wiring in P. putida and its uses in biocatalysis, in particular for the production of non-growth-related biochemicals, we developed and present here a genome-scale constraint-based model of the metabolism of P. putida KT2440. Network reconstruction and flux balance analysis (FBA enabled definition of the structure of the metabolic network, identification of knowledge gaps, and pin-pointing of essential metabolic functions, facilitating thereby the refinement of gene annotations. FBA and flux variability analysis were used to analyze the properties, potential, and limits of the model. These analyses allowed identification, under various conditions, of key features of metabolism such as growth yield, resource distribution, network robustness, and gene essentiality. The model was validated with data from continuous cell cultures, high-throughput phenotyping data, (13C-measurement of internal flux distributions, and specifically generated knock-out mutants. Auxotrophy was correctly predicted in 75% of the cases. These systematic analyses revealed that the metabolic network structure is the main factor determining the accuracy of predictions, whereas biomass composition has negligible influence. Finally, we drew on the model to devise metabolic engineering strategies to improve production of polyhydroxyalkanoates, a class of biotechnologically useful compounds whose synthesis is not coupled to cell survival. The solidly validated model yields valuable insights into genotype-phenotype relationships and provides a sound framework to explore this versatile

  20. Dynamics of development and dispersal in sessile microbial communities: examples from Pseudomonas aeruginosa and Pseudomonas putida model biofilms

    DEFF Research Database (Denmark)

    Klausen, M.; Gjermansen, Morten; Kreft, J.-U.;

    2006-01-01

    Surface-associated microbial communities in many cases display dynamic developmental patterns. Model biofilms formed by Pseudomonas aeruginosa and Pseudomonas putida in laboratory flow-chamber setups represent examples of such behaviour. Dependent on the experimental conditions the bacteria in...... organisms do not possess comprehensive genetic programs for biofilm development. Instead the bacteria appear to have evolved a number of different mechanisms to optimize surface colonization, of which they express a subset in response to the prevailing environmental conditions. These mechanisms include the...... ability to regulate cellular adhesiveness and migration in response to micro-environmental signals including those secreted by the bacteria themselves....

  1. Pseudomonas fluorescens and Pseudomonas putida for Promoting Growth of Jatropha curcas Seedling Root

    Directory of Open Access Journals (Sweden)

    Sri Sumarsih

    2012-05-01

    Full Text Available Pseudomonas fluorescens and P. putida are Plant Growth Promoting Rhizobacteria (PGPR that can produce growth hormone. The objective of this study is to know the effects of those two combined species of PGPR on seedling root growth of Jatropha curcas. The condition of the seedling root determines the success of dry land cultivation. The root which has wider coverage, is larger in number, and is bigger in diameter makes seedling more resistant to stress in dry land environment. In the experiment, two kinds of plant materials are used for seedling, the Jatropha seed and stem material, which are treated in a mixed culture of PGPR. For the Jatropha seed, this mixed culture of PGPR is given at the same time of cultivating the sprout on the seedling medium. For the stem cutting, the PGPR is poured in together during the first watering of the seedling cultivation medium. In the fourthweek, the observed growth parameters are root length, root diameter, primary and secondary lateral root numbers, Root Length Density (RLD, Frequency of Lateral Root (FLR, and Specific Root Length (SRL. These data are analyzed using analysis of variant with DMRT test at 0.05 level of significance. The result of this study shows that PGPR tend to reduce FLR values on the seedling root made from seeds. On the seedling root made from stem cutting, PGPR increase the root length, primary and secondary lateral root numbers, root diameter, FLR and SRL values as well.

  2. Crystallization and preliminary X-ray diffraction analysis of alanine racemase from Pseudomonas putida YZ-26

    International Nuclear Information System (INIS)

    A recombinant alanine racemase from the Pseudomonas putida YZ-26, has been crystallized by the sitting-drop vapor-diffusion method and X-ray diffraction data were collected to 2.4 Å. A recombinant form of alanine racemase (Alr) from Pseudomonas putida YZ-26 has been crystallized by the sitting-drop vapour diffusion method. X-ray diffraction data were collected to 2.4 Å resolution. The crystals belong to the space group C2221, with unit-cell parameters a = 118.08, b = 141.86, c = 113.83 Å, and contain an Alr dimer in the asymmetric unit. The Matthews coefficient and the solvent content were calculated to be 2.8 Å3 Da−1 and approximately 50%, respectively

  3. Kontinuierliche Co-Kultur von Tetrahymena thermophila und Pseudomonas putida in einem Bioreaktor

    OpenAIRE

    Hauptmann, Ulla

    2000-01-01

    Im Rahmen der vorliegenden Arbeit wurde ein mikrobielles Ökosystem in einem kontinuierlich betriebenen gerührten Bioreaktor (CSTR) im Labormaßstab etabliert und seine Wachstumskinetik untersucht. In diesem in vitro Räuber-Beute-System wurden der Ciliat Tetrahymena thermophila und das Bakterium Pseudomonas putida über einen Zeitraum von mehr als 400 Stunden gemeinsam kultiviert. Die Interaktion von Bakterien und Protozoen stellt einen elementaren Prozess in der Ökologie nahezu jedes G...

  4. Toxicity of Ionic Liquids and Organic Solvents towards Escherichia coli and Pseudomonas putida

    OpenAIRE

    Wood, Nicola

    2011-01-01

    i. AbstractThe University of ManchesterNicola WoodDegree of Doctor of PhilosophyToxicity of Ionic Liquids and Organic Solvents towards Escherichia coli and Pseudomonas putidaFunded by BBSRC2011By turning to biological catalysts such as whole cell microorganisms it is possible to both improve the specificity of a (bio) chemical transformation with the added benefit of reducing the energy demands of a number of synthetic processes which currently use chemical catalysts. The replacement of chemi...

  5. Mono-chlorophenol degradation by pseudomonas putida CP1 and a mixed microbial population

    OpenAIRE

    Farrell, Alan

    2000-01-01

    A commercial mixed culture, Biolyte HAB, degraded mono-chlorophenols using a metci- cleavage pathway. 2- and 3-chlorophenol degradation was incomplete, leading to the accumulation of dead-end metabolites. Biolyte HAB was capable of the complete degradation of 2.34 mM 4-chlorophenol, via the intermediate 5-chloro-2- hydroxymuconic semialdehyde, using the meta- cleavage pathway. Pseudomonas putida CPI degraded mono-chlorophenols to completion via an orthocleavage pathway. The ability of P. ...

  6. Optimierung von Pseudomonas putida für die Produktion niedermolekularer Verbindungen

    OpenAIRE

    Graf, Nadja

    2013-01-01

    Das Gram-negative Bakterium Pseudomonas putida ist aufgrund seines ausgeprägten Stoffwechsels für aliphatische und aromatische Kohlenwasserstoffe in den letzten Jahren zu einem der wichtigsten Wirtsorganismen in der Biotechnologie geworden. Für die gezielte Manipulation seines Genoms stehen gentechnische Methoden zur Verfügung, die jedoch ineffektiv und nur schwer zu handhaben sind. Basierend auf der Toxizität des Antimetaboliten 5-Fluoruracil und der Wirkung der Uracilphosphoribosyl-Transfer...

  7. Toxicity Testing of Pristine and Aged Silver Nanoparticles in Real Wastewaters Using Bioluminescent Pseudomonas putida

    OpenAIRE

    Florian Mallevre; Camille Alba; Craig Milne; Simon Gillespie; Teresa F. Fernandes; Thomas J. Aspray

    2016-01-01

    Impact of aging on nanoparticle toxicity in real matrices is scarcely investigated due to a lack of suitable methodologies. Herein, the toxicity of pristine and aged silver nanoparticles (Ag NPs) to a bioluminescent Pseudomonas putida bioreporter was measured in spiked crude and final wastewater samples (CWs and FWs, respectively) collected from four wastewater treatment plants (WWTPs). Results showed lower toxicity of pristine Ag NPs in CWs than in FWs. The effect of the matrix on the eventu...

  8. Addition of Aromatic Substrates Restores Trichloroethylene Degradation Activity in Pseudomonas putida F1

    OpenAIRE

    Morono, Yuki; Unno, Hajime; TANJI, Yasunori; Hori, Katsutoshi

    2004-01-01

    The rate of trichloroethylene (TCE) degradation by toluene dioxygenase (TDO) in resting cells of Pseudomonas putida F1 gradually decreased and eventually stopped within 1.5 h, as in previous reports. However, the subsequent addition of toluene, which is the principal substrate of TDO, resulted in its immediate degradation without a lag phase. After the consumption of toluene, degradation of TCE restarted at a rate similar to its initial degradation, suggesting that this degradation was mediat...

  9. Preferential Utilization of Aromatic Compounds over Glucose by Pseudomonas putida CSV86

    OpenAIRE

    Basu, Aditya; Apte, Shree K.; Phale, Prashant S.

    2006-01-01

    Pseudomonas putida CSV86, a naphthalene-degrading organism, exhibited diauxic growth on aromatic compounds plus glucose, with utilization of aromatics in the first log phase and of glucose in the second log phase. Glucose supplementation did not suppress the activity of degrading enzymes, which were induced upon addition of aromatic compounds. The induction was inhibited by chloramphenicol, suggesting that de novo protein synthesis was essential. Cells showed cometabolism of aromatic compound...

  10. Antimicrobial activities of commercial nanoparticles against an environmental soil microbe, Pseudomonas putida KT2440

    OpenAIRE

    Gajjar, Priyanka; Pettee, Brian; Britt, David W.; Huang, Wenjie; Johnson, William P.; Anderson, Anne J.

    2009-01-01

    Background The release of heavy metal-containing nanoparticles (NP) into the environment may be harmful to the efficacy of beneficial microbes that function in element cycling, pollutant degradation and plant growth. Nanoparticles of Ag, CuO and ZnO are of interest as antimicrobials against pathogenic bacteria. We demonstrate here their antimicrobial activity against the beneficial soil microbe, Pseudomonas putida KT2440. Results Toxicity was detected in a KT2440 construct possessing a plasmi...

  11. Characterization of the OCT plasmid encoding alkane oxidation and mercury resistance in Pseudomonas putida.

    OpenAIRE

    Harder, P A; Kunz, D A

    1986-01-01

    Transformation of Pseudomonas putida and analysis for plasmid DNA revealed that both n-alkane oxidation and mercury resistance are encoded on a single 220-megadalton OCT plasmid molecule. Derivatives of OCT having lost the mercury resistance function could be readily isolated and contained a smaller plasmid estimated to be 170 megadaltons. The results show that segregation of the mercury resistance property occurs not by loss of a separate MER plasmid as previously thought but by a deletion i...

  12. Colony morphology and transcriptome profiling of Pseudomonas putida KT2440 and its mutants deficient in alginate or all EPS synthesis under controlled matric potentials

    DEFF Research Database (Denmark)

    Gülez, Gamze; Altintas, Ali; Fazli, Mustafa;

    2014-01-01

    Pseudomonas putida is a versatile bacterial species adapted to soil and its fluctuations. Like many other species living in soil, P. putida often faces water limitation. Alginate, an exopolysaccharide (EPS) produced by P. putida, is known to create hydrated environments and alleviate the effect o...

  13. The Pseudomonas putida Lon protease is involved in N-acyl homoserine lactone quorum sensing regulation

    Directory of Open Access Journals (Sweden)

    Leoni Livia

    2007-07-01

    Full Text Available Abstract Background In Pseudomonas putida and Pseduomonas aeruginosa, the similar PpuR/RsaL/PpuI and LasR/RsaL/LasI acyl homoserine lactones (AHLs quorum sensing (QS systems have been shown to be under considerable regulation by other global regulators. A major regulator is the RsaL protein which strongly directly represses the transcription of the P. putida ppuI and P. aeruginosa lasI AHL synthases. In this study we screened a transposon mutant bank of P. putida in order to identify if any other regulators were involved in negative regulation of AHL QS. Results In our screen we identified three Tn5 mutants which displayed overproduction of AHLs in P. putida strain WCS358. Two of the mutants had a Tn5 located in the rsaL gene, whereas in one mutant the transposon was located in the lon protease gene. Lon proteases play important roles in protein quality control via degradation of misfolded proteins. It was determined that in the P. putida lon mutant, AHL levels, PpuR levels and ppuI promoter activity all increased significantly; we therefore postulated that PpuR is a target for Lon. The Lon protease had no effect on AHL production in P. aeruginosa. Conclusion The Lon protease is a negative regulator of AHL production in P. putida WCS358. The Lon protease has also been shown by others to influence AHL QS in Vibrio fischeri and Agrobacterium tumefaciens and can thus become an important regulator of AHL QS timing and regulation in bacteria.

  14. Establishment of pseudomonas putida strains for sensitive detection of heavy metals in effluents

    International Nuclear Information System (INIS)

    The objective of this study was to isolate a mutant of Pseudomonas putida that is more sensitive to heavy metal toxicants in water than the wild type. P. putida was the organism chosen in this study as it occurs naturally in unpolluted waters, is nonpathogenic, aerobic and because it is commonly applied in bacterial toxicity assays due to its sensitivity to toxicants. Three methods of mutagenesis were employed, which included N-methyl-N'-nitro-N-nitrosoguanidine (NG) ; ultraviolet light and transposon-mediated mutagenesis in order to generate as wide a range of mutants as possible. Four mutants, which were more sensitive to mercury, copper, lead, zinc, cadmium and silver were isolated using the NG method of mutagenesis. These mutants were designated strains 53, 56, 60 and 61 and were characterized as P. putida strains on the basis of Gram staining, biochemical reactions and immunological properties. The sensitivity of the mutants to a variety of industrial effluents was compared to that of the parent strain using a bacterial growth test. Using industrial effluents, one of the mutants, namely strain 56 was found to be more sensitive than the parent strain on 71.4% of the tests. Strains 60 and 61 were also both more sensitive than the parent strain on 42.9% of the occasions using industrial effluents. The uptake rates of radioactive mercury were measured for the parent strain of P. putida and the mutants that were found to be more sensitive to mercury

  15. Effect of Pseudomonas putida on growth and anthocyanin pigment in two poinsettia (Euphorbia pulcherrima) cultivars.

    Science.gov (United States)

    Zulueta-Rodriguez, Ramon; Cordoba-Matson, Miguel Victor; Hernandez-Montiel, Luis Guillermo; Murillo-Amador, Bernardo; Rueda-Puente, Edgar; Lara, Liliana

    2014-01-01

    Pseudomonas putida is plant growth promoting rhizobacteria (PGPR) that have the capacity to improve growth in plants. The purpose of this study was to determine growth and anthocyanin pigmentation of the bracts in two poinsettia Euphorbia pulcherrima cultivars (Prestige and Sonora Marble) using three strains of P. putida, as well as a mixture of the three (MIX). Comparison with the control group indicated for the most part that Prestige grew better than the Sonora Marble cultivars with the PGPR strains. Prestige with the MIX strain grew better compared to control for the number of cyathia (83 versus 70.4), volume of roots (45 versus 3  cm(3)), number of leaves (78 versus 58), and area of leaf (1,788 versus 1,331 cm(2)), except for the number of flowers (8.8 versus 11.6). To the naked eye, coloration of plants appeared identical in color compared to the control group. For all plants with P. putida strains, there was less anthocyanin pigment, but biomass was always greater with PGPR strains. Nevertheless, to the naked eye, the coloration of the plants appeared identical in color compared to the control group. This is the first study reporting the positive effects of P. putida rhizobacteria treatments on growth of poinsettia cultivars. PMID:25097888

  16. Effect of Pseudomonas putida on Growth and Anthocyanin Pigment in Two Poinsettia (Euphorbia pulcherrima Cultivars

    Directory of Open Access Journals (Sweden)

    Ramon Zulueta-Rodriguez

    2014-01-01

    Full Text Available Pseudomonas putida is plant growth promoting rhizobacteria (PGPR that have the capacity to improve growth in plants. The purpose of this study was to determine growth and anthocyanin pigmentation of the bracts in two poinsettia Euphorbia pulcherrima cultivars (Prestige and Sonora Marble using three strains of P. putida, as well as a mixture of the three (MIX. Comparison with the control group indicated for the most part that Prestige grew better than the Sonora Marble cultivars with the PGPR strains. Prestige with the MIX strain grew better compared to control for the number of cyathia (83 versus 70.4, volume of roots (45 versus 35 cm3, number of leaves (78 versus 58, and area of leaf (1,788 versus 1,331 cm2, except for the number of flowers (8.8 versus 11.6. To the naked eye, coloration of plants appeared identical in color compared to the control group. For all plants with P. putida strains, there was less anthocyanin pigment, but biomass was always greater with PGPR strains. Nevertheless, to the naked eye, the coloration of the plants appeared identical in color compared to the control group. This is the first study reporting the positive effects of P. putida rhizobacteria treatments on growth of poinsettia cultivars.

  17. Metal Inhibition of Growth and Manganese Oxidation in Pseudomonas putida GB-1

    Science.gov (United States)

    Pena, J.; Sposito, G.

    2009-12-01

    Biogenic manganese oxides (MnO2) are ubiquitous nanoparticulate minerals that contribute to the adsorption of nutrient and toxicant metals, the oxidative degradation of various organic compounds, and the respiration of metal-reducing bacteria in aquatic and terrestrial environments. The formation of these minerals is catalyzed by a diverse and widely-distributed group of bacteria and fungi, often through the enzymatic oxidation of aqueous Mn(II) to Mn(IV). In metal-impacted ecosystems, toxicant metals may alter the viability and metabolic activity of Mn-oxidizing organisms, thereby limiting the conditions under which biogenic MnO2 can form and diminishing their potential as adsorbent materials. Pseudomonas putida GB-1 (P. putida GB-1) is a model Mn-oxidizing laboratory culture representative of freshwater and soil biofilm-forming bacteria. Manganese oxidation in P. putida GB-1 occurs via two single-electron-transfer reactions, involving a multicopper oxidase enzyme found on the bacterial outer membrane surface. Near the onset of the stationary phase of growth, dark brown MnO2 particles are deposited in a matrix of bacterial cells and extracellular polymeric substances, thus forming heterogeneous biomineral assemblages. In this study, we assessed the influence of various transition metals on microbial growth and manganese oxidation capacity in a P. putida GB-1 culture propagated in a nutrient-rich growth medium. The concentration-response behavior of actively growing P. putida GB-1 cells was investigated for Fe, Co, Ni, Cu and Zn at pH ≈ 6 in the presence and absence of 1 mM Mn. Toxicity parameters such as EC0, EC50 and Hillslope, and EC100 were obtained from the sigmoidal concentration-response curves. The extent of MnO2 formation in the presence of the various metal cations was documented 24, 50, 74 and 104 h after the metal-amended medium was inoculated. Toxicity values were compared to twelve physicochemical properties of the metals tested. Significant

  18. Genetic analysis of plant endophytic Pseudomonas putida BP25 and chemo-profiling of its antimicrobial volatile organic compounds.

    Science.gov (United States)

    Sheoran, Neelam; Valiya Nadakkakath, Agisha; Munjal, Vibhuti; Kundu, Aditi; Subaharan, Kesavan; Venugopal, Vibina; Rajamma, Suseelabhai; Eapen, Santhosh J; Kumar, Aundy

    2015-04-01

    Black pepper associated bacterium BP25 was isolated from root endosphere of apparently healthy cultivar Panniyur-5 that protected black pepper against Phytophthora capsici and Radopholus similis - the major production constraints. The bacterium was characterized and mechanisms of its antagonistic action against major pathogens are elucidated. The polyphasic phenotypic analysis revealed its identity as Pseudomonas putida. Multi locus sequence typing revealed that the bacterium shared gene sequences with several other isolates representing diverse habitats. Tissue localization assays exploiting green fluorescence protein expression clearly indicated that PpBP25 endophytically colonized not only its host plant - black pepper, but also other distantly related plants such as ginger and arabidopsis. PpBP25 colonies could be enumerated from internal tissues of plants four weeks post inoculation indicated its stable establishment and persistence in the plant system. The bacterium inhibited broad range of pathogens such as Phytophthora capsici, Pythium myriotylum, Giberella moniliformis, Rhizoctonia solani, Athelia rolfsii, Colletotrichum gloeosporioides and plant parasitic nematode, Radopholus similis by its volatile substances. GC/MS based chemical profiling revealed presence of Heneicosane; Tetratetracontane; Pyrrolo [1,2-a] pyrazine-1,4-dione, hexahydro-3-(2-methylpropyl); Tetracosyl heptafluorobutyrate; 1-3-Eicosene, (E)-; 1-Heneicosanol; Octadecyl trifluoroacetate and 1-Pentadecene in PpBP25 metabolite. Dynamic head space GC/MS analysis of airborne volatiles indicated the presence of aromatic compounds such as 1-Undecene;Disulfide dimethyl; Pyrazine, methyl-Pyrazine, 2,5-dimethyl-; Isoamyl alcohol; Pyrazine, methyl-; Dimethyl trisulfide, etc. The work paved way for profiling of broad spectrum antimicrobial VOCs in endophytic PpBP25 for crop protection. PMID:25801973

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

    DEFF Research Database (Denmark)

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

    2003-01-01

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

  20. Pseudomonas putida KT2442 cultivated on glucose accumulates poly(3-hydroxyalkanoates) consisting of saturated and unsaturated monomers.

    OpenAIRE

    Huijberts, G N; Eggink, G.; Waard, P. de; Huisman, G W; Witholt, B

    1992-01-01

    The biosynthesis of poly(3-hydroxyalkanoates) (PHAs) by Pseudomonas putida KT2442 during growth on carbohydrates was studied. PHAs isolated from P. putida cultivated on glucose, fructose, and glycerol were found to have a very similar monomer composition. In addition to the major constituent 3-hydroxydecanoate, six other monomers were found to be present: 3-hydroxyhexanoate, 3-hydroxyoctanoate, 3-hydroxydodecanoate, 3-hydroxydodecenoate, 3-hydroxytetradecanoate, and 3-hydroxytetradecenoate. T...

  1. System for improving the production of polyhydroxyalkanoates (bioplastic) by fermentation from glycerol using a genetically modified strain of Pseudomonas putida

    OpenAIRE

    Fernández Escapa, Isabel; Cerro, Carlos del; Garcia, José Luis; Prieto, María Auxiliadora

    2011-01-01

    [EN] The present invention relates to the development and execution of a method for facilitating the production of substances, in particular polyhydroxyalkanoates (PHAs), in Pseudomonas putida from glycerol. For said purpose, a mutant strain derived from P. putida has been constructed which comprises a mutation in the chromosome of the glpR gene that enables the bacteria to use glycerol as a source of carbon and energy in a more efficient manner, and thus makes it possible to improve the prod...

  2. Comparison of kinetics of active tetracycline uptake and active tetracycline efflux in sensitive and plasmid RP4-containing Pseudomonas putida.

    OpenAIRE

    Hedstrom, R C; Crider, B P; Eagon, R. G.

    1982-01-01

    Membrane vesicles prepared from tetracycline-sensitive cells of Pseudomonas putida took up tetracycline by an active transport system with an apparent Km of 2.5 mM and a Vmax of 50 nmol min-1 mg protein-1. In contrast, resistance determinant RP4-containing P. putida had an active high-affinity efflux system for tetracycline with a Km of 2.0 to 3.54 microM and a Vmax of 0.15 nmol min-1 mg protein-1. Thus, the efflux system of tetracycline-resistant P. putida(RP4) had an average of 1,000-fold g...

  3. Pseudomonas putida KT2440 Strain Metabolizes Glucose through a Cycle Formed by Enzymes of the Entner-Doudoroff, Embden-Meyerhof-Parnas, and Pentose Phosphate Pathways.

    Science.gov (United States)

    Nikel, Pablo I; Chavarría, Max; Fuhrer, Tobias; Sauer, Uwe; de Lorenzo, Víctor

    2015-10-23

    The soil bacterium Pseudomonas putida KT2440 lacks a functional Embden-Meyerhof-Parnas (EMP) pathway, and glycolysis is known to proceed almost exclusively through the Entner-Doudoroff (ED) route. To investigate the raison d'être of this metabolic arrangement, the distribution of periplasmic and cytoplasmic carbon fluxes was studied in glucose cultures of this bacterium by using (13)C-labeled substrates, combined with quantitative physiology experiments, metabolite quantification, and in vitro enzymatic assays under both saturating and non-saturating, quasi in vivo conditions. Metabolic flux analysis demonstrated that 90% of the consumed sugar was converted into gluconate, entering central carbon metabolism as 6-phosphogluconate and further channeled into the ED pathway. Remarkably, about 10% of the triose phosphates were found to be recycled back to form hexose phosphates. This set of reactions merges activities belonging to the ED, the EMP (operating in a gluconeogenic fashion), and the pentose phosphate pathways to form an unforeseen metabolic architecture (EDEMP cycle). Determination of the NADPH balance revealed that the default metabolic state of P. putida KT2440 is characterized by a slight catabolic overproduction of reducing power. Cells growing on glucose thus run a biochemical cycle that favors NADPH formation. Because NADPH is required not only for anabolic functions but also for counteracting different types of environmental stress, such a cyclic operation may contribute to the physiological heftiness of this bacterium in its natural habitats. PMID:26350459

  4. Kinetics of cometabolic degradation of 2-chlorophenol and phenol by Pseudomonas putida

    Institute of Scientific and Technical Information of China (English)

    Xing-ping LIU

    2009-01-01

    In order to address the complex cometabolic degradation of toxic compounds,batch experiments on the biodegradation of 2-chlorophenol (2-CP) and phenol by Pseudomonas putida were carried out.The experimental results show that 2-CP has an inhibitory effect on cell growth and phenol degradation,which demonstrates that the interaction between substrates affects cell growth and substrate degradation.A kinetic model of cell growth and substrate transformation was also developed.The square of the correlation coefficient from the experiment was 0.97,indicating that this model properly simulates the cometabolic degradation of 2-CP and phenol.

  5. Trichloroethylene removal and oxidation toxicity mediated by toluene dioxygenase of Pseudomonas putida.

    OpenAIRE

    Heald, S.; Jenkins, R. O.

    1994-01-01

    Whole cells of Pseudomonas putida containing toluene dioxygenase were able to remove all detectable trichloroethylene (TCE) from assay mixtures. The capacity of cells to remove TCE was 77 microM/mg of protein with an initial rate of removal of 5.2 nmol/min/ng of protein. TCE oxidation resulted in a decrease in the growth rate of cultures and caused rapid cell death. Addition of dithiothreitol to assay mixtures increased the TCE removal capacity of cells by up to 67% but did not prevent TCE-me...

  6. The ssu Locus Plays a Key Role in Organosulfur Metabolism in Pseudomonas putida S-313

    OpenAIRE

    Kahnert, Antje; Vermeij, Paul; Wietek, Claudia; James, Peter; Leisinger, Thomas; Kertesz, Michael A.

    2000-01-01

    Pseudomonas putida S-313 can utilize a broad range of aromatic sulfonates as sulfur sources for growth in sulfate-free minimal medium. The sulfonates are cleaved monooxygenolytically to yield the corresponding phenols. miniTn5 mutants of strain S-313 which were no longer able to desulfurize arylsulfonates were isolated and were found to carry transposon insertions in the ssuEADCBF operon, which contained genes for an ATP-binding cassette-type transporter (ssuABC), a two-component reduced flav...

  7. TOL Plasmid Carriage Enhances Biofilm Formation and Increases Extracellular DNA Content in Pseudomonas Putida KT2440

    DEFF Research Database (Denmark)

    Smets, Barth F.; D'Alvise, Paul; Yankelovich, T.; Sjøholm, O.; Jin, Y.; Wuertz, S.

    Adherent growth of Pseudomonas putida KT2440 with and without the TOL plasmid (pWWO) at the solid-liquid and air-liquid interface was examined. We compared biofilm formation on glass in flow cells, and assayed pellicle (air-liquid interface biofilm) formation in stagnant liquid cultures by confocal...... laser scanning microscopy. The TOL-carrying strains formed pellicles and thick biofilms, whereas the same strains without the plasmid displayed little adherent growth. Microscopy using fluorescent nucleic acid- specific stains (cytox orange, propidium iodide) revealed differences in production of...

  8. Molecular characterization of the mde operon involved in L-methionine catabolism of Pseudomonas putida.

    OpenAIRE

    H. Inoue; Inagaki, K.; Eriguchi, S I; Tamura, T.; Esaki, N; Soda, K; Tanaka, H.

    1997-01-01

    A 15-kb region of Pseudomonas putida chromosomal DNA containing the mde operon and an upstream regulatory gene (mdeR) has been cloned and sequenced. The mde operon contains two structural genes involved in L-methionine degradative metabolism: the already-identified mdeA, which encodes L-methionine gamma-lyase (H. Inoue, K. Inagaki, M. Sugimoto, N. Esaki, K. Soda, and H. Tanaka. J. Biochem. (Tokyo) 117:1120-1125, 1995), and mdeB, which encodes a homologous protein to the homodimeric-type E1 co...

  9. Purification of a branched-chain keto acid dehydrogenase from Pseudomonas putida.

    OpenAIRE

    Sokatch, J R; McCully, V; Roberts, C M

    1981-01-01

    We purified branched-chain keto acid dehydrogenase to a specific activity of 10 mumol/min per mg of protein from Pseudomonas putida grown on valine. The purified enzyme was active with 2-ketoisovalerate, 2-ketoisocaproate, and 2-keto-3-methylvalerate in a ratio of 1.0:0.8:0.7 but showed no activity with either pyruvate or 2-ketoglutarate. There were four polypeptides in the purified enzyme (molecular weights, 49,000, 46,000, 39,000, and 37,000). The purified enzyme was deficient in the specif...

  10. Antibiotic resistance determinants in a Pseudomonas putida strain isolated from a hospital.

    Directory of Open Access Journals (Sweden)

    Lázaro Molina

    Full Text Available Environmental microbes harbor an enormous pool of antibiotic and biocide resistance genes that can impact the resistance profiles of animal and human pathogens via horizontal gene transfer. Pseudomonas putida strains are ubiquitous in soil and water but have been seldom isolated from humans. We have established a collection of P. putida strains isolated from in-patients in different hospitals in France. One of the isolated strains (HB3267 kills insects and is resistant to the majority of the antibiotics used in laboratories and hospitals, including aminoglycosides, ß-lactams, cationic peptides, chromoprotein enediyne antibiotics, dihydrofolate reductase inhibitors, fluoroquinolones and quinolones, glycopeptide antibiotics, macrolides, polyketides and sulfonamides. Similar to other P. putida clinical isolates the strain was sensitive to amikacin. To shed light on the broad pattern of antibiotic resistance, which is rarely found in clinical isolates of this species, the genome of this strain was sequenced and analysed. The study revealed that the determinants of multiple resistance are both chromosomally-borne as well as located on the pPC9 plasmid. Further analysis indicated that pPC9 has recruited antibiotic and biocide resistance genes from environmental microorganisms as well as from opportunistic and true human pathogens. The pPC9 plasmid is not self-transmissible, but can be mobilized by other bacterial plasmids making it capable of spreading antibiotic resistant determinants to new hosts.

  11. Antibiotic resistance determinants in a Pseudomonas putida strain isolated from a hospital.

    Science.gov (United States)

    Molina, Lázaro; Udaondo, Zulema; Duque, Estrella; Fernández, Matilde; Molina-Santiago, Carlos; Roca, Amalia; Porcel, Mario; de la Torre, Jesús; Segura, Ana; Plesiat, Patrick; Jeannot, Katy; Ramos, Juan-Luis

    2014-01-01

    Environmental microbes harbor an enormous pool of antibiotic and biocide resistance genes that can impact the resistance profiles of animal and human pathogens via horizontal gene transfer. Pseudomonas putida strains are ubiquitous in soil and water but have been seldom isolated from humans. We have established a collection of P. putida strains isolated from in-patients in different hospitals in France. One of the isolated strains (HB3267) kills insects and is resistant to the majority of the antibiotics used in laboratories and hospitals, including aminoglycosides, ß-lactams, cationic peptides, chromoprotein enediyne antibiotics, dihydrofolate reductase inhibitors, fluoroquinolones and quinolones, glycopeptide antibiotics, macrolides, polyketides and sulfonamides. Similar to other P. putida clinical isolates the strain was sensitive to amikacin. To shed light on the broad pattern of antibiotic resistance, which is rarely found in clinical isolates of this species, the genome of this strain was sequenced and analysed. The study revealed that the determinants of multiple resistance are both chromosomally-borne as well as located on the pPC9 plasmid. Further analysis indicated that pPC9 has recruited antibiotic and biocide resistance genes from environmental microorganisms as well as from opportunistic and true human pathogens. The pPC9 plasmid is not self-transmissible, but can be mobilized by other bacterial plasmids making it capable of spreading antibiotic resistant determinants to new hosts. PMID:24465371

  12. Metabolic Engineering of Pseudomonas putida KT2440 to Produce Anthranilate from Glucose.

    Science.gov (United States)

    Kuepper, Jannis; Dickler, Jasmin; Biggel, Michael; Behnken, Swantje; Jäger, Gernot; Wierckx, Nick; Blank, Lars M

    2015-01-01

    The Pseudomonas putida KT2440 strain was engineered in order to produce anthranilate (oAB, ortho-aminobenzoate), a precursor of the aromatic amino acid tryptophan, from glucose as sole carbon source. To enable the production of the metabolic intermediate oAB, the trpDC operon encoding an anthranilate phosphoribosyltransferase (TrpD) and an indole-3-glycerol phosphate synthase (TrpC), were deleted. In addition, the chorismate mutase (pheA) responsible for the conversion of chorismate over prephenate to phenylpyruvate was deleted in the background of the deletion of trpDC to circumvent a potential drain of precursor. To further increase the oAB production, a feedback insensitive version of 3-deoxy-D-arabino-heptulosonate-7-phosphate synthase encoded by the aroG (D146N) gene and an anthranilate synthase (trpE (S40F) G) were overexpressed separately and simultaneously in the deletion mutants. With optimized production conditions in a tryptophan-limited fed-batch process a maximum of 1.54 ± 0.3 g L(-1) (11.23 mM) oAB was obtained with the best performing engineered P. putida KT2440 strain (P. putida ΔtrpDC pSEVA234_aroG (D146N) _trpE (S40F) G). PMID:26635771

  13. Metabolic engineering of Pseudomonas putida KT2440 to produce anthranilate from glucose

    Directory of Open Access Journals (Sweden)

    Jannis eKuepper

    2015-11-01

    Full Text Available The Pseudomonas putida KT2440 strain was engineered in order to produce anthranilate (oAB, ortho-aminobenzoate, a precursor of the aromatic amino acid tryptophan, from glucose as sole carbon source. To enable the production of the metabolic intermediate oAB, the trpDC operon encoding an anthranilate phosphoribosyltransferase (TrpD and an indole-3-glycerol phosphate synthase (TrpC, were deleted. In addition, the chorismate mutase (pheA responsible for the conversion of chorismate over prephenate to phenylpyruvate was deleted in the background of the deletion of trpDC to circumvent a potential drain of precursor. To further increase the oAB production, a feedback insensitive version of 3-deoxy-D-arabino-heptulosonate-7-phosphate (DAHP synthase encoded by the aroGD146N gene and an anthranilate synthase (trpES40FG were overexpressed separately and simultaneously in the deletion mutants. With optimized production conditions in a tryptophan-limited fed-batch process a maximum of 1.54 ±0.3 g L-1 (11.23 mM oAB was obtained with the best performing engineered P. putida KT2440 strain (P. putida ∆trpDC pSEVA234_aroGD146N_trpES40FG.

  14. Metabolic engineering of Pseudomonas putida for production of docosahexaenoic acid based on a myxobacterial PUFA synthase.

    Science.gov (United States)

    Gemperlein, Katja; Zipf, Gregor; Bernauer, Hubert S; Müller, Rolf; Wenzel, Silke C

    2016-01-01

    Long-chain polyunsaturated fatty acids (LC-PUFAs) can be produced de novo via polyketide synthase-like enzymes known as PUFA synthases, which are encoded by pfa biosynthetic gene clusters originally discovered from marine microorganisms. Recently similar gene clusters were detected and characterized in terrestrial myxobacteria revealing several striking differences. As the identified myxobacterial producers are difficult to handle genetically and grow very slowly we aimed to establish heterologous expression platforms for myxobacterial PUFA synthases. Here we report the heterologous expression of the pfa gene cluster from Aetherobacter fasciculatus (SBSr002) in the phylogenetically distant model host bacteria Escherichia coli and Pseudomonas putida. The latter host turned out to be the more promising PUFA producer revealing higher production rates of n-6 docosapentaenoic acid (DPA) and docosahexaenoic acid (DHA). After several rounds of genetic engineering of expression plasmids combined with metabolic engineering of P. putida, DHA production yields were eventually increased more than threefold. Additionally, we applied synthetic biology approaches to redesign and construct artificial versions of the A. fasciculatus pfa gene cluster, which to the best of our knowledge represents the first example of a polyketide-like biosynthetic gene cluster modulated and synthesized for P. putida. Combination with the engineering efforts described above led to a further increase in LC-PUFA production yields. The established production platform based on synthetic DNA now sets the stage for flexible engineering of the complex PUFA synthase. PMID:26617065

  15. Metabolomics reveals the physiological response of Pseudomonas putida KT2440 (UWC1) after pharmaceutical exposure.

    Science.gov (United States)

    Currie, Felicity; Broadhurst, David I; Dunn, Warwick B; Sellick, Christopher A; Goodacre, Royston

    2016-04-22

    Human pharmaceuticals have been detected in wastewater treatment plants, rivers, and estuaries throughout Europe and the United States. It is widely acknowledged that there is insufficient information available to determine whether prolonged exposure to low levels of these substances is having an impact on the microbial ecology in such environments. In this study we attempt to measure the effects of exposing cultures of Pseudomonas putida KT2440 (UWC1) to six pharmaceuticals by looking at differences in metabolite levels. Initially, we used Fourier transform infrared (FT-IR) spectroscopy coupled with multivariate analysis to discriminate between cell cultures exposed to different pharmaceuticals. This suggested that on exposure to propranolol there were significant changes in the lipid complement of P. putida. Metabolic profiling with gas chromatography-mass spectrometry (GC-MS), coupled with univariate statistical analyses, was used to identify endogenous metabolites contributing to discrimination between cells exposed to the six drugs. This approach suggested that the energy reserves of exposed cells were being expended and was particularly evident on exposure to propranolol. Adenosine triphosphate (ATP) concentrations were raised in P. putida exposed to propranolol. Increased energy requirements may be due to energy dependent efflux pumps being used to remove propranolol from the cell. PMID:26932201

  16. Novel broad host range shuttle vectors for expression in Escherichia coli, Bacillus subtilis and Pseudomonas putida.

    Science.gov (United States)

    Troeschel, Sonja Christina; Thies, Stephan; Link, Olga; Real, Catherine Isabell; Knops, Katja; Wilhelm, Susanne; Rosenau, Frank; Jaeger, Karl-Erich

    2012-10-15

    Novel shuttle vectors named pEBP were constructed to allow the gene expression in different bacterial hosts including Escherichia coli, Bacillus subtilis and Pseudomonas putida. These vectors share the inducible promoters P(T7) and P(Xyl) and a cos site to enable packaging of plasmid DNA into phage, and carry different multiple cloning sites and antibiotic resistance genes. Vector pEBP41 generally replicates episomally while pEBP18 replicates episomally in Gram-negative bacteria only, but integrates into the chromosome of B. subtilis. Plasmid copy numbers determined for E. coli and P. putida were in the range of 5-50 per cell. The functionality of pEBP18 and pEBP41 was confirmed by expression of two lipolytic enzymes, namely lipase A from B. subtilis and cutinase from the eukaryotic fungus Fusarium solani pisi in three different host strains. Additionally, we report here the construction of a T7 RNA polymerase-based expression strain of P. putida. PMID:22440389

  17. ISOLATION AND CHARACTERIZATION OF A MOLYBDENUM-REDUCING, PHENOL- AND CATECHOL-DEGRADING PSEUDOMONAS PUTIDA STRAIN AMR-12 IN SOILS FROM EGYPT

    Directory of Open Access Journals (Sweden)

    M. Abd. AbdEl-Mongy

    2016-02-01

    Full Text Available Sites contaminated with both heavy metals and organic xenobiotic pollutants warrants the effective use of either a multitude of bacterial degraders or bacteria having the capacity to detoxify numerous toxicants simultaneously. A molybdenum-reducing bacterium with the capacity to degrade phenolics is reported. Molybdenum (sodium molybdate reduction was optimum between pH 6.0 and 7.0 and between 20 and 30 °C. The most suitable electron donor was glucose. A narrow range of phosphate concentrations between 5.0 and 7.5 mM was required for optimal reduction, while molybdate between 20 and 30 mM were needed for optimal reduction. The scanning absorption spectrum of the molybdenum blue produced indicated that Mo-blue is a reduced phosphomolybdate. Molybdenum reduction was inhibited by the heavy metals mercury, silver and chromium. Biochemical analysis identified the bacterium as Pseudomonas putida strain Amr-12. Phenol and phenolics cannot support molybdenum reduction. However, the bacterium was able to grow on the phenolic compounds (phenol and catechol with observable lag periods. Maximum growth on phenol and catechol occurred around the concentrations of 600 mg∙L-1. The ability of this bacterium to detoxify molybdenum and grown on toxic phenolic makes this bacterium an important tool for bioremediation.

  18. Entner-Doudoroff pathway for sulfoquinovose degradation in Pseudomonas putida SQ1.

    Science.gov (United States)

    Felux, Ann-Katrin; Spiteller, Dieter; Klebensberger, Janosch; Schleheck, David

    2015-08-01

    Sulfoquinovose (SQ; 6-deoxy-6-sulfoglucose) is the polar head group of the plant sulfolipid SQ-diacylglycerol, and SQ comprises a major proportion of the organosulfur in nature, where it is degraded by bacteria. A first degradation pathway for SQ has been demonstrated recently, a "sulfoglycolytic" pathway, in addition to the classical glycolytic (Embden-Meyerhof) pathway in Escherichia coli K-12; half of the carbon of SQ is abstracted as dihydroxyacetonephosphate (DHAP) and used for growth, whereas a C3-organosulfonate, 2,3-dihydroxypropane sulfonate (DHPS), is excreted. The environmental isolate Pseudomonas putida SQ1 is also able to use SQ for growth, and excretes a different C3-organosulfonate, 3-sulfolactate (SL). In this study, we revealed the catabolic pathway for SQ in P. putida SQ1 through differential proteomics and transcriptional analyses, by in vitro reconstitution of the complete pathway by five heterologously produced enzymes, and by identification of all four organosulfonate intermediates. The pathway follows a reaction sequence analogous to the Entner-Doudoroff pathway for glucose-6-phosphate: It involves an NAD(+)-dependent SQ dehydrogenase, 6-deoxy-6-sulfogluconolactone (SGL) lactonase, 6-deoxy-6-sulfogluconate (SG) dehydratase, and 2-keto-3,6-dideoxy-6-sulfogluconate (KDSG) aldolase. The aldolase reaction yields pyruvate, which supports growth of P. putida, and 3-sulfolactaldehyde (SLA), which is oxidized to SL by an NAD(P)(+)-dependent SLA dehydrogenase. All five enzymes are encoded in a single gene cluster that includes, for example, genes for transport and regulation. Homologous gene clusters were found in genomes of other P. putida strains, in other gamma-Proteobacteria, and in beta- and alpha-Proteobacteria, for example, in genomes of Enterobacteria, Vibrio, and Halomonas species, and in typical soil bacteria, such as Burkholderia, Herbaspirillum, and Rhizobium. PMID:26195800

  19. Enhancing Indigo Production by Over-Expression of the Styrene Monooxygenase in Pseudomonas putida.

    Science.gov (United States)

    Cheng, Lei; Yin, Sheng; Chen, Min; Sun, Baoguo; Hao, Shuai; Wang, Chengtao

    2016-08-01

    As an important traditional blue dye, indigo has been used in food and textile industry for centuries, which can be produced via the styrene oxygenation pathway in Pseudomonas putida. Hence, the styrene monooxygenase gene styAB and oxide isomerase gene styC are over-expressed in P. putida to investigate their roles in indigo biosynthesis. RT-qPCR analysis indicated that transcriptions of styA and styB were increased by 2500- and 750-folds in the styAB over-expressed strain B4-01, compared with the wild-type strain B4, consequently significantly enhancing the indole monooxygenase activity. Transcription of styC was also increased by 100-folds in the styC over-expressed strain B4-02. Besides, styAB over-expression slightly up-regulated the transcription of styC in B4-01, while styC over-expression hardly exerted an effect on the transcriptional levels of styA and styB and indole monooxygenase activity in B4-02. Furthermore, shaking flask experiments showed that indigo production in B4-01 reached 52.13 mg L(-1) after 24 h, which was sevenfold higher than that in B4. But no obvious increase in indigo yield was observed in B4-02. Over-expression of styAB significantly enhanced the indigo production, revealing that the monooxygenase STYAB rather than oxide isomerase STYC probably acted as the key rate-limiting enzyme in the indigo biosynthesis pathway in P. putida. This work provided a new strategy for enhancing indigo production in Pseudomonas. PMID:27154464

  20. Enhanced Biological Phosphorus Removal with Pseudomonas putida GM6 from Activated Sludge

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The enhanced biological phosphorus removal (EBPR) method is widely adopted for phosphorus removal from wastewater, yet little is known about its microbiological and molecular mechanisms. Therefore, it is difficult to predict and control the deterioration of the EBPR process in a large-scale municipal sewage treatment plant. This study used a novel strain isolated in the laboratory, Pseudomonas putida GM6, which had a high phosphate accumulating ability and could recover rapidly from the deteriorated system and enhance the capability of phosphorus removal in activated sludge. Strain GM6 marked with gfp gene, which was called GMTR, was delivered into a bench-scale sequencing batch reactor (SBR)of low efficiency, to investigate the colonization of GMTR and removal of phosphorus. After 21 days, the proportion of GMTR in the total bacteria of the sludge reached 9.2%, whereas the phosphorus removal rate was 96%, with an effluent concentration of about 0.2 mg L-1. In the reactor with the addition of GMTR, phosphorus was removed quickly, in 1 h under anaerobic conditions, and in 2 h under aerobic conditions. These evidences were characteristic of EBPR processes.Field testing was conducted at a hospital sewage treatment facility with low phosphorus removal capability. Twentyone days after Pseudononas putida GM6 was added, effluent phosphorus concentration remained around 0.3 mg L-1,corresponding to a removal rate of 96.8%. It was therefore demonstrated that Pseudomonas putida GM6 could be used for a quick startup and enhancement of wastewater biological phosphorus removal, which provided a scientific basis for potential large-scale engineering application.

  1. Bioaugmentation of a 4-chloronitrobenzene contaminated soil with Pseudomonas putida ZWL73

    International Nuclear Information System (INIS)

    The strain Pseudomonas putida ZWL73, which metabolizes 4-chloronitrobenzene (4CNB) by a partial-reductive pathway, was inoculated into lab-scale 4CNB-contaminated soil for bioaugmentation purposes in this study. The degradation of 4CNB was clearly stimulated, as indicated with the gradual accumulation of ammonium and chloride. Simultaneously, the diversity and quantity of cultivable heterotrophic bacteria decreased due to 4CNB contamination, while the quantity of 4CNB-resistant bacteria increased. During the bioaugmentation, denaturing gradient gel electrophoresis analysis showed the changes of diversity in dominant populations of intrinsic soil microbiota. The results showed that Alphaproteobacteria and Betaproteobacteria were not distinctly affected, but Actinobacteria were apparently stimulated. In addition, an interesting dynamic within Acidobacteria was observed, as well as an influence on ammonia-oxidizing bacteria population. These combined findings demonstrate that the removal of 4CNB in soils by inoculating strain ZWL73 is feasible, and that specific populations in soils rapidly changed in response to 4CNB contamination and subsequent bioaugmentation. - Pseudomonas putida ZWL73 can accelerate 4CNB removal in lab-scale soils, causing dynamic changes within intrinsic Actinobacteria and Acidobacteria

  2. Bioaugmentation of a 4-chloronitrobenzene contaminated soil with Pseudomonas putida ZWL73

    Energy Technology Data Exchange (ETDEWEB)

    Niu Guilan [State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071 (China); Graduate School, Chinese Academy of Sciences, Beijing 100049 (China); Zhang Junjie [State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071 (China); Zhao Shuo [State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071 (China); Graduate School, Chinese Academy of Sciences, Beijing 100049 (China); Liu Hong [State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071 (China); Boon, Nico [Laboratory of Microbial Ecology and Technology (LabMET), Ghent University, Coupure Links 653, B-9000 Gent (Belgium); Zhou Ningyi [State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071 (China)], E-mail: n.zhou@pentium.whiov.ac.cn

    2009-03-15

    The strain Pseudomonas putida ZWL73, which metabolizes 4-chloronitrobenzene (4CNB) by a partial-reductive pathway, was inoculated into lab-scale 4CNB-contaminated soil for bioaugmentation purposes in this study. The degradation of 4CNB was clearly stimulated, as indicated with the gradual accumulation of ammonium and chloride. Simultaneously, the diversity and quantity of cultivable heterotrophic bacteria decreased due to 4CNB contamination, while the quantity of 4CNB-resistant bacteria increased. During the bioaugmentation, denaturing gradient gel electrophoresis analysis showed the changes of diversity in dominant populations of intrinsic soil microbiota. The results showed that Alphaproteobacteria and Betaproteobacteria were not distinctly affected, but Actinobacteria were apparently stimulated. In addition, an interesting dynamic within Acidobacteria was observed, as well as an influence on ammonia-oxidizing bacteria population. These combined findings demonstrate that the removal of 4CNB in soils by inoculating strain ZWL73 is feasible, and that specific populations in soils rapidly changed in response to 4CNB contamination and subsequent bioaugmentation. - Pseudomonas putida ZWL73 can accelerate 4CNB removal in lab-scale soils, causing dynamic changes within intrinsic Actinobacteria and Acidobacteria.

  3. Ni2+ -uptake in Pseudomonas putida strain S4: a possible role of Mg2+ -uptake pump

    Indian Academy of Sciences (India)

    V N Tripathi; S Srivastava

    2006-03-01

    Essential metal ion homeostasis is based on regulated uptake of metal ions, both during its scarcity and abundance. Pseudomonas putida strain S4, a multimetal resistant bacterium, was employed to investigate Ni2+ entry into cells. It was observed that Mg2+ regulates the entry of Ni2+ and by this plays a protective role to minimize Ni2+ toxicity in this strain. This protection was evident in both growth as well as viability. Intracellular accumulation of Ni2+ varied in accordance with Mg2+ concentrations in the medium. It was hypothesized that Ni2+ enters the cell using a broad Mg2+ pump, i.e. the CorA system, as the CorA inhibitor, i.e. Co(III) Hex, also inhibits Ni2+ uptake. This led to the inference that Mg2+-based protection was basically due to competitive inhibition of Ni2+ uptake. We also show that Zn2+ can further regulate the entry of Ni2+.

  4. Effect of exopolymers on oxidative dissolution of natural rhodochrosite by Pseudomonas putida strain MnB1: An electrochemical study

    International Nuclear Information System (INIS)

    Highlights: • The biogeochemical behavior of natural rhodochrosite was investigated by electrochemical methods. • Bacterial exopolymers contributed to the increasing dissolution of natural rhodochrosite. • Oxidative dissolution of natural rhodochrosite was well explained by Tafel and EIS analysis. - Abstract: Oxidative dissolution of natural rhodochrosite by the Mn(II) oxidizing bacterium Pseudomonas putida strain MnB1 was investigated based on batch and electrochemical experiments using natural rhodochrosite as the working electrode. Tafel curves and batch experiments revealed that bacterial exopolymers (EPS) significantly increased dissolution of natural rhodochrosite. The corrosion current significantly increased with reaction time for EPS treatment. However, the corrosion process was blocked in the presence of cells plus extra EPS due to formation of the passivation layer. Moreover, the scanning electron microscopy and the energy dispersive spectroscopy (SEM–EDS) results showed that the surface of the natural rhodochrosite was notably changed in the presence of EPS alone or/and bacterial cells. This study is helpful for understanding the role of EPS in bacterially oxidation of Mn(II). It also indicates that the Mn(II) oxidizing bacteria may exert their effects on Mn(II) cycle and other biological and biogeochemical processes much beyond their local ambient environment because of the catalytically dissolution of solid Mn(II) by EPS and the possible long distance transport of the detached EPS

  5. Bioluminescent Bioreporter Pseudomonas putida TVA8 as a Detector of Water Pollution. Operational Conditions and Selectivity of Free Cells Sensor

    Czech Academy of Sciences Publication Activity Database

    Kuncová, Gabriela; Pazlarová, J.; Hlavatá, Alena; Ripp, S.; Sayler, G.S.

    2011-01-01

    Roč. 11, č. 3 (2011), s. 882-887. ISSN 1470-160X R&D Projects: GA MŠk ME 893 Institutional research plan: CEZ:AV0Z40720504 Keywords : whole-cell biosensor * bioluminiscence * pseudomonas putida TVA8 Subject RIV: EI - Biotechnology ; Bionics Impact factor: 2.695, year: 2011

  6. Crystal Structure of the Leucine Aminopeptidase from Pseudomonas putida Reveals the Molecular Basis for its Enantioselectivity and Broad Substrate Specificity

    NARCIS (Netherlands)

    Kale, Avinash; Pijning, Tjaard; Sonke, Theo; Dijkstra, Bauke W.; Thunnissen, Andy-Mark W. H.; Guss, M.

    2010-01-01

    The zinc-dependent leucine aminopeptidase from Pseudomonas putida (ppLAP) is an important enzyme for the industrial production of enantiomerically pure amino acids. To provide a better understanding of its structure function relationships, the enzyme was studied by X-ray crystallography. Crystal str

  7. Novel Dehalogenase Mechanism for 2,3-Dichloro-1-Propanol Utilization in Pseudomonas putida Strain MC4

    NARCIS (Netherlands)

    Arif, Muhammad Ilan; Samin, Ghufrana; van Leeuwen, Jan G. E.; Oppentocht, Jantien; Janssen, Dick B.

    2012-01-01

    A Pseudomonas putida strain (MC4) that can utilize 2,3-dichloro-1-propanol (DCP) and several aliphatic haloacids and haloalcohols as sole carbon and energy source for growth was isolated from contaminated soil. Degradation of DCP was found to start with oxidation and concomitant dehalogenation catal

  8. Regulation of phenylacetic acid uptake is σ54 dependent in Pseudomonas putida CA-3

    Directory of Open Access Journals (Sweden)

    O' Mahony Mark M

    2011-10-01

    Full Text Available Abstract Background Styrene is a toxic and potentially carcinogenic alkenylbenzene used extensively in the polymer processing industry. Significant quantities of contaminated liquid waste are generated annually as a consequence. However, styrene is not a true xenobiotic and microbial pathways for its aerobic assimilation, via an intermediate, phenylacetic acid, have been identified in a diverse range of environmental isolates. The potential for microbial bioremediation of styrene waste has received considerable research attention over the last number of years. As a result the structure, organisation and encoded function of the genes responsible for styrene and phenylacetic acid sensing, uptake and catabolism have been elucidated. However, a limited understanding persists in relation to host specific regulatory molecules which may impart additional control over these pathways. In this study the styrene degrader Pseudomonas putida CA-3 was subjected to random mini-Tn5 mutagenesis and mutants screened for altered styrene/phenylacetic acid utilisation profiles potentially linked to non-catabolon encoded regulatory influences. Results One mutant, D7, capable of growth on styrene, but not on phenylacetic acid, harboured a Tn5 insertion in the rpoN gene encoding σ54. Complementation of the D7 mutant with the wild type rpoN gene restored the ability of this strain to utilise phenylacetic acid as a sole carbon source. Subsequent RT-PCR analyses revealed that a phenylacetate permease, PaaL, was expressed in wild type P. putida CA-3 cells utilising styrene or phenylacetic acid, but could not be detected in the disrupted D7 mutant. Expression of plasmid borne paaL in mutant D7 was found to fully restore the phenylacetic acid utilisation capacity of the strain to wild type levels. Bioinformatic analysis of the paaL promoter from P. putida CA-3 revealed two σ54 consensus binding sites in a non-archetypal configuration, with the transcriptional start site

  9. Growth independent rhamnolipid production from glucose using the non-pathogenic Pseudomonas putida KT2440

    Directory of Open Access Journals (Sweden)

    Wittgens Andreas

    2011-10-01

    Full Text Available Abstract Background Rhamnolipids are potent biosurfactants with high potential for industrial applications. However, rhamnolipids are currently produced with the opportunistic pathogen Pseudomonas aeruginosa during growth on hydrophobic substrates such as plant oils. The heterologous production of rhamnolipids entails two essential advantages: Disconnecting the rhamnolipid biosynthesis from the complex quorum sensing regulation and the opportunity of avoiding pathogenic production strains, in particular P. aeruginosa. In addition, separation of rhamnolipids from fatty acids is difficult and hence costly. Results Here, the metabolic engineering of a rhamnolipid producing Pseudomonas putida KT2440, a strain certified as safety strain using glucose as carbon source to avoid cumbersome product purification, is reported. Notably, P. putida KT2440 features almost no changes in growth rate and lag-phase in the presence of high concentrations of rhamnolipids (> 90 g/L in contrast to the industrially important bacteria Bacillus subtilis, Corynebacterium glutamicum, and Escherichia coli. P. putida KT2440 expressing the rhlAB-genes from P. aeruginosa PAO1 produces mono-rhamnolipids of P. aeruginosa PAO1 type (mainly C10:C10. The metabolic network was optimized in silico for rhamnolipid synthesis from glucose. In addition, a first genetic optimization, the removal of polyhydroxyalkanoate formation as competing pathway, was implemented. The final strain had production rates in the range of P. aeruginosa PAO1 at yields of about 0.15 g/gglucose corresponding to 32% of the theoretical optimum. What's more, rhamnolipid production was independent from biomass formation, a trait that can be exploited for high rhamnolipid production without high biomass formation. Conclusions A functional alternative to the pathogenic rhamnolipid producer P. aeruginosa was constructed and characterized. P. putida KT24C1 pVLT31_rhlAB featured the highest yield and titer reported

  10. Regulation of phenylacetic acid uptake is sigma54 dependent in Pseudomonas putida CA-3.

    LENUS (Irish Health Repository)

    O' Leary, Niall D

    2011-10-13

    Abstract Background Styrene is a toxic and potentially carcinogenic alkenylbenzene used extensively in the polymer processing industry. Significant quantities of contaminated liquid waste are generated annually as a consequence. However, styrene is not a true xenobiotic and microbial pathways for its aerobic assimilation, via an intermediate, phenylacetic acid, have been identified in a diverse range of environmental isolates. The potential for microbial bioremediation of styrene waste has received considerable research attention over the last number of years. As a result the structure, organisation and encoded function of the genes responsible for styrene and phenylacetic acid sensing, uptake and catabolism have been elucidated. However, a limited understanding persists in relation to host specific regulatory molecules which may impart additional control over these pathways. In this study the styrene degrader Pseudomonas putida CA-3 was subjected to random mini-Tn5 mutagenesis and mutants screened for altered styrene\\/phenylacetic acid utilisation profiles potentially linked to non-catabolon encoded regulatory influences. Results One mutant, D7, capable of growth on styrene, but not on phenylacetic acid, harboured a Tn5 insertion in the rpoN gene encoding σ54. Complementation of the D7 mutant with the wild type rpoN gene restored the ability of this strain to utilise phenylacetic acid as a sole carbon source. Subsequent RT-PCR analyses revealed that a phenylacetate permease, PaaL, was expressed in wild type P. putida CA-3 cells utilising styrene or phenylacetic acid, but could not be detected in the disrupted D7 mutant. Expression of plasmid borne paaL in mutant D7 was found to fully restore the phenylacetic acid utilisation capacity of the strain to wild type levels. Bioinformatic analysis of the paaL promoter from P. putida CA-3 revealed two σ54 consensus binding sites in a non-archetypal configuration, with the transcriptional start site being resolved by

  11. Activity and three-dimensional distribution of toluene-degrading Pseudomonas putida in a multispecies biofilm assessed by quantitative in situ hybridization and scanning confocal laser microscopy

    DEFF Research Database (Denmark)

    Møller, Søren; Pedersen, Anne Rathmann; Poulsen, L.K.;

    1996-01-01

    As a representative member of the toluene-degrading population in a biofilter for waste gas treatment, Pseudomonas putida was investigated with a 16S rRNA targeting probe, The three-dimensional distribution of P. putida was visualized in the biofilm matrix by scanning confocal laser microscopy...... at a maximal rate in the biofilm environment, Assuming that the rRNA content reflected the cellular activity, a lower toluene degradation rate for P. putida present in the biofilm could be estimated, This calculation Indicated that P. putida mas responsible for a significant part (65%) of the toluene...... consequently P. putida may be actively degrading toluene in all regions of the biofilm. Furthermore, measurements of growth rate-related parameters fur P. putida showed reduced I RNA content and cell size (relative to that ill a batch culture), indicating that the P. putida population mas not degrading toluene...

  12. In situ biosurfactant production and hydrocarbon removal by Pseudomonas putida CB-100 in bioaugmented and biostimulated oil-contaminated soil.

    Science.gov (United States)

    Ángeles, Martínez-Toledo; Refugio, Rodríguez-Vázquez

    2013-01-01

    In situ biosurfactant (rhamnolipid) production by Pseudomonas putida CB-100 was achieved during a bioaugmented and biostimulated treatment to remove hydrocarbons from aged contaminated soil from oil well drilling operations. Rhamnolipid production and contaminant removal were determined for several treatments of irradiated and non-irradiated soils: nutrient addition (nitrogen and phosphorus), P. putida addition, and addition of both (P. putida and nutrients). The results were compared against a control treatment that consisted of adding only sterilized water to the soils. In treatment with native microorganisms (non-irradiated soils) supplemented with P. putida, the removal of total petroleum hydrocarbons (TPH) was 40.6%, the rhamnolipid production was 1.54 mg/kg, and a surface tension of 64 mN/m was observed as well as a negative correlation (R = -0.54; p biosurfactant production and surface tension were 2.03 mg/kg and 67.3 mN/m, respectively. In irradiated soil treated with P. putida, TPH removal was 24.5% with rhamnolipid generation of 1.79 mg/kg and 65.6 mN/m of surface tension, and a correlation between bacterial growth and biosurfactant production (R = -0.64; p biosurfactants were produced, and the surface tension was 55.6 mN/m. In summary, in irradiated and non-irradiated soils, in situ rhamnolipid production by P. putida enhanced TPH decontamination of the soil. PMID:24294259

  13. Screening and optimization of low-cost medium for Pseudomonas putida Rs-198 culture using RSM

    Directory of Open Access Journals (Sweden)

    Yanjie Peng

    2014-12-01

    Full Text Available The plant growth-promoting rhizobacterial strain Pseudomonas putida Rs-198 was isolated from salinized soils from Xinjiang Province. We optimized the composition of the low-cost medium of P. putida Rs-198 based on its bacterial concentration, as well as its phosphate-dissolving and indole acetic acid (IAA-producing capabilities using the response surface methodology (RSM, and a mathematical model was developed to show the effect of each medium component and its interactions on phosphate dissolution and IAA production. The model predicted a maximum phosphate concentration in medium containing 63.23 mg/L inorganic phosphate with 49.22 g/L corn flour, 14.63 g/L soybean meal, 2.03 g/L K2HPO4, 0.19 g/L MnSO4 and 5.00 g/L NaCl. The maximum IAA concentration (18.73 mg/L was predicted in medium containing 52.41 g/L corn flour, 15.82 g/L soybean meal, 2.40 g/L K2HPO4, 0.17 g/L MnSO4 and 5.00 g/L NaCl. These predicted values were also verified through experiments, with a cell density of 10(13 cfu/mL, phosphate dissolution of 64.33 mg/L, and IAA concentration of 18.08 mg/L. The excellent correlation between predicted and measured values of each model justifies the validity of both the response models. The study aims to provide a basis for industrialized fermentation using P. putida Rs-198.

  14. Pseudomonas putida response in membrane bioreactors under salicylic acid-induced stress conditions

    Energy Technology Data Exchange (ETDEWEB)

    Collado, Sergio; Rosas, Irene; González, Elena; Gutierrez-Lavin, Antonio; Diaz, Mario, E-mail: mariodiaz@uniovi.es

    2014-02-01

    Highlights: • MBR under feed-induced stress conditions: starvation and changing feeding conditions. • High capacity of MBR to withstand high variations in feed loads. • Slow biofilm formation under starvation conditions during the first days. • Observed growth of P. putida for substrate to microorganism ratio higher than 0.6 g/g. • Maximum specific growth rate and growth yield values of around 37.5 h{sup −1} and 0.5 g/g. - Abstract: Starvation and changing feeding conditions are frequently characteristics of wastewater treatment plants. They are typical causes of unsteady-state operation of biological systems and provoke cellular stress. The response of a membrane bioreactor functioning under feed-induced stress conditions is studied here. In order to simplify and considerably amplify the response to stress and to obtain a reference model, a pure culture of Pseudomonas putida was selected instead of an activated sludge and a sole substrate (salicylic acid) was employed. The system degraded salicylic acid at 100–1100 mg/L with a high level of efficiency, showed rapid acclimation without substrate or product inhibition phenomena and good stability in response to unsteady states caused by feed variations. Under starvation conditions, specific degradation rates of around 15 mg/g h were achieved during the adaptation of the biomass to the new conditions and no biofilm formation was observed during the first days of experimentation using an initial substrate to microorganisms ratio lower than 0.1. When substrate was added to the reactor as pulses resulting in rapidly changing concentrations, P. putida growth was observed only for substrate to microorganism ratios higher than 0.6, with a maximum Y{sub X/S} of 0.5 g/g. Biofilm development under changing feeding conditions was fast, biomass detachment only being significant for biomass concentrations on the membrane surface that were higher than 16 g/m{sup 2}.

  15. Pseudomonas putida response in membrane bioreactors under salicylic acid-induced stress conditions

    International Nuclear Information System (INIS)

    Highlights: • MBR under feed-induced stress conditions: starvation and changing feeding conditions. • High capacity of MBR to withstand high variations in feed loads. • Slow biofilm formation under starvation conditions during the first days. • Observed growth of P. putida for substrate to microorganism ratio higher than 0.6 g/g. • Maximum specific growth rate and growth yield values of around 37.5 h−1 and 0.5 g/g. - Abstract: Starvation and changing feeding conditions are frequently characteristics of wastewater treatment plants. They are typical causes of unsteady-state operation of biological systems and provoke cellular stress. The response of a membrane bioreactor functioning under feed-induced stress conditions is studied here. In order to simplify and considerably amplify the response to stress and to obtain a reference model, a pure culture of Pseudomonas putida was selected instead of an activated sludge and a sole substrate (salicylic acid) was employed. The system degraded salicylic acid at 100–1100 mg/L with a high level of efficiency, showed rapid acclimation without substrate or product inhibition phenomena and good stability in response to unsteady states caused by feed variations. Under starvation conditions, specific degradation rates of around 15 mg/g h were achieved during the adaptation of the biomass to the new conditions and no biofilm formation was observed during the first days of experimentation using an initial substrate to microorganisms ratio lower than 0.1. When substrate was added to the reactor as pulses resulting in rapidly changing concentrations, P. putida growth was observed only for substrate to microorganism ratios higher than 0.6, with a maximum YX/S of 0.5 g/g. Biofilm development under changing feeding conditions was fast, biomass detachment only being significant for biomass concentrations on the membrane surface that were higher than 16 g/m2

  16. Activity and three-dimensional distribution of toluene-degrading Pseudomonas putida in a multispecies biofilm assessed by quantitative in situ hybridization and scanning confocal laser microscopy

    DEFF Research Database (Denmark)

    Møller, Søren; Pedersen, Anne Rathmann; Poulsen, L.K.; Arvin, Erik; Molin, Søren

    1996-01-01

    As a representative member of the toluene-degrading population in a biofilter for waste gas treatment, Pseudomonas putida was investigated with a 16S rRNA targeting probe, The three-dimensional distribution of P. putida was visualized in the biofilm matrix by scanning confocal laser microscopy...

  17. PH-stat fed-batch process to enhance the production of cis, cis-muconate from benzoate by Pseudomonas putida KT2440-JD1

    NARCIS (Netherlands)

    Duuren, J.B.J.H. van; Wijte, D.; Karge, B.; Martins dos Santos, V.A.; Yang, Y.; Mars, A.E.; Eggink, G.

    2012-01-01

    Pseudomonas putida KT2440-JD1 is able to cometabolize benzoate to cis, cis-muconate in the presence of glucose as growth substrate. P. putida KT2440-JD1 was unable to grow in the presence of concentrations above 50 mM benzoate or 600 mM cis, cis-muconate. The inhibitory effects of both compounds wer

  18. Improved p-hydroxybenzoate production by engineered Pseudomonas putida S12 by using a mixed-substrate feeding strategy

    OpenAIRE

    Meijnen, J.P.; Verhoef, S.; Briedjlal, A.A.; de Winde, J. H.; Ruijssenaars, H.J.

    2011-01-01

    The key precursors for p-hydroxybenzoate production by engineered Pseudomonas putida S12 are phosphoenolpyruvate (PEP) and erythrose-4-phosphate (E4P), for which the pentose phosphate (PP) pathway is an important source. Since PP pathway fluxes are typically low in pseudomonads, E4P and PEP availability is a likely bottleneck for aromatics production which may be alleviated by stimulating PP pathway fluxes via co-feeding of pentoses in addition to glucose or glycerol. As P. putida S12 lacks t...

  19. Degradation of waste waters from olive oil mills by Yarrowia lipolytica ATCC 20255 and Pseudomonas putida

    Energy Technology Data Exchange (ETDEWEB)

    De Felice, B.; Pontecorvo, G.; Carfagna, M. [Univ. of Naples, Caserta (Italy). Inst. of Biology

    1997-12-31

    Waste water from olive oil processing may cause severe pollution in the Mediterranean area, since they have a high level of chemical oxygen demand (COD) (100-200 g/l) and contain other organic and inorganic compounds. In all olive oil producing countries, the reduction of pollution in olive oil mill waste waters at reasonable costs and using techniques suitable for most industrial applications is an unsolved problem. For this paper, the yeast Yarrowia lipolytica ATCC 20255 was grown on waste waters from an olive oil mill in a 3.5 l fermenter under batch culture conditions. The results showed that the yeast was capable of reducing the COD value by 80% in 24 h. In this way, a useful biomass of 22.45 g/l as single cell protein (SCP) and enzyme lipase were produced. During this process, most of the organic and inorganic substances were consumed, only aromatic pollutants were still present in the fermentation effluents. Therefore, we used a phenol degrader, namely Pseudomonas putida, to reduce phenolic compounds in the fermentation effluents after removing Yarrowia lipolytica cells. P. putida was effective in reducing phenols in only 12 h. (orig.)

  20. Assessing the safety of Pseudomonas putida introduction in the environment: an overview of ecotoxicological tests.

    Science.gov (United States)

    de Castro, Vera Lúcia S S; Jonsson, Cláudio Martin; Silva, Célia Maria M; de Holanda Nunes Maia, Aline

    2010-04-01

    Risk assessment guidelines for the environmental release of microbial agents are performed in a tiered sequence which includes evaluation of exposure effects on non-target organisms. However, it becomes important to verify whether environmental risk assessment from temperate studies is applicable to tropical countries, as Brazil. Pseudomonas putida is a bacteria showing potential to be used for environmental applications as bioremediation and plant disease control. This study investigates the effects of this bacteria exposure on rodents and aquatic organisms (Daphnia similis) that are recommended to be used as non-target organism in environmental risk assessments. Also, the microbial activity in three different soils under P. putida exposure was evaluated. Rats did not show clinical alterations, although the agent was recovered 16h after the exposure in lung homogenates. The bacteria did not reduce significantly the reproduction and survival of D. similis. The soil enzymatic activities presented fluctuating values after inoculation with bacteria. The measurement of perturbations in soil biochemical characteristics is presented as an alternative way of monitoring the overall effects of the microbial agent to be introduced even in first stage (Tier I) of the risk assessment in tropical ecosystems. PMID:19800380

  1. Homology modeling and function of trehalose synthase from Pseudomonas putida P06.

    Science.gov (United States)

    Su, Jing; Wang, Tengfei; Ma, Chunling; Li, Zhongkui; Li, Zhenzhen; Wang, Ruiming

    2014-05-01

    Trehalose is a non-reducing disaccharide that has wide applications in the food industry and pharmaceutical manufacturing. Trehalose synthase (TreS) from Pseudomonas putida P06 catalyzes the reversible interconversion of maltose and trehalose and may have applications in the food industry. However, the catalytic mechanism of TreS is not well understood. Here, we investigated the structural characteristics of this enzyme by homology modeling. The highly conserved Asp294 residue was identified to be critical for catalytic activity. In addition, flexible docking studies of the enzyme-substrate system were performed to predict the interactions between TreS and its substrate, maltose. Amino acids that interact extensively with the substrate and stabilize the substrate in an orientation suitable for enzyme catalysis were identified. The importance of these residues for catalytic activity was confirmed by the biochemical characterization of the relevant mutants generated by site-directed mutagenesis. PMID:24563286

  2. TOL plasmid carriage enhances biofilm formation and increases extracellular DNA content in Pseudomonas putida KT2440

    DEFF Research Database (Denmark)

    D'Alvise, Paul; Sjoholm, O.R.; Yankelevich, T.;

    2010-01-01

    Adherent growth of Pseudomonas putida KT2440 with and without the TOL plasmid (pWWO) at the solid-liquid and air-liquid interface was examined. We compared biofilm formation on glass in flow cells, and assayed pellicle (air-liquid interface biofilm) formation in stagnant liquid cultures by confocal...... laser scanning microscopy. The TOL-carrying strains formed pellicles and thick biofilms, whereas the same strains without the plasmid displayed little adherent growth. Microscopy using fluorescent nucleic acid-specific stains revealed differences in the production of extracellular polymeric substances......: TOL carriage leads to more extracellular DNA (eDNA) in pellicles and biofilms. Pellicles were dissolved by DNase I treatment. Enhanced cell lysis due to plasmid carriage was ruled out as the mechanism for eDNA release. We report, for the first time, that carriage of a conjugative plasmid leads to...

  3. Novel polyhydroxyalkanoate copolymers produced in Pseudomonas putida by metagenomic polyhydroxyalkanoate synthases.

    Science.gov (United States)

    Cheng, Jiujun; Charles, Trevor C

    2016-09-01

    Bacterially produced biodegradable polyhydroxyalkanoates (PHAs) with versatile properties can be achieved using different PHA synthases (PhaCs). This work aims to expand the diversity of known PhaCs via functional metagenomics and demonstrates the use of these novel enzymes in PHA production. Complementation of a PHA synthesis-deficient Pseudomonas putida strain with a soil metagenomic cosmid library retrieved 27 clones expressing either class I, class II, or unclassified PHA synthases, and many did not have close sequence matches to known PhaCs. The composition of PHA produced by these clones was dependent on both the supplied growth substrates and the nature of the PHA synthase, with various combinations of short-chain-length (SCL) and medium-chain-length (MCL) PHA. These data demonstrate the ability to isolate diverse genes for PHA synthesis by functional metagenomics and their use for the production of a variety of PHA polymer and copolymer mixtures. PMID:27333909

  4. TOL Plasmid Carriage Enhances Biofilm Formation and Increases Extracellular DNA Content in Pseudomonas Putida KT2440

    DEFF Research Database (Denmark)

    Smets, Barth F.; D'Alvise, Paul; Yankelovich, T.;

    Adherent growth of Pseudomonas putida KT2440 with and without the TOL plasmid (pWWO) at the solid-liquid and air-liquid interface was examined. We compared biofilm formation on glass in flow cells, and assayed pellicle (air-liquid interface biofilm) formation in stagnant liquid cultures by confocal...... laser scanning microscopy. The TOL-carrying strains formed pellicles and thick biofilms, whereas the same strains without the plasmid displayed little adherent growth. Microscopy using fluorescent nucleic acid- specific stains (cytox orange, propidium iodide) revealed differences in production...... combined with specific cytostains; release of cytoplasmic material was assayed by a β-glucosidase assay. Enhanced cell lysis due to plasmid carriage was ruled out as the mechanism for eDNA release. We report, for the first time, that carriage of a conjugative plasmid leads to increased biofilm formation...

  5. Competition triggers plasmid-mediated enhancement of substrate utilisation in Pseudomonas putida.

    Directory of Open Access Journals (Sweden)

    Hiren Joshi

    Full Text Available Competition between species plays a central role in the activity and structure of communities. Stable co-existence of diverse organisms in communities is thought to be fostered by individual tradeoffs and optimization of competitive strategies along resource gradients. Outside the laboratory, microbes exist as multispecies consortia, continuously interacting with one another and the environment. Survival and proliferation of a particular species is governed by its competitive fitness. Therefore, bacteria must be able to continuously sense their immediate environs for presence of competitors and prevailing conditions. Here we present results of our investigations on a novel competition sensing mechanism in the rhizosphere-inhabiting Pseudomonas putida KT2440, harbouring gfpmut3b-modified Kan(R TOL plasmid. We monitored benzyl alcohol (BA degradation rate, along with GFP expression profiling in mono species and dual species cultures. Interestingly, enhanced plasmid expression (monitored using GFP expression and consequent BA degradation were observed in dual species consortia, irrespective of whether the competitor was a BA degrader (Pseudomonas aeruginosa or a non-degrader (E. coli. Attempts at elucidation of the mechanistic aspects of induction indicated the role of physical interaction, but not of any diffusible compounds emanating from the competitors. This contention is supported by the observation that greater induction took place in presence of increasing number of competitors. Inert microspheres mimicking competitor cell size and concentration did not elicit any significant induction, further suggesting the role of physical cell-cell interaction. Furthermore, it was also established that cell wall compromised competitor had minimal induction capability. We conclude that P. putida harbouring pWW0 experience a competitive stress when grown as dual-species consortium, irrespective of the counterpart being BA degrader or not. The immediate

  6. Expression of Pseudomonas aeruginosa transposable phages in Pseudomonas putida cells. I. Establishment of lysogeny and lytic growth efficiency

    International Nuclear Information System (INIS)

    Expression of the genomes of Pseudomonas aeruginosa transposable phages (TP) in the cells of a heterologous host, P. putida PpGl, was studied. A high efficiency of TP lytic growth in PpGl cells was obtained both after zygotic induction following RP4::TP plasmid transfer and after thermoinduction of PpGl cells lysogenic for thermoinducible prophage D3112cts15. Characteristic for PpGl cells was a high TP yield (20-25 phage D3112cts15 particles per cell), which was evidence of a high level of TP transposition in cells of this species. The frequency of RP4::TP transfer into PpGl and PA01 cells was equal, but the lysogeny detection rat was somewhat lower in PpGl. Pseudomonas aeruginosa TP can integrate into the PpGl chromosome, producing inducible lysogens. The presence of RP4 is not necessary for the expression of the TP genome in PpGl cells. The D3112cts15 TP may be used for interspecific transduction of plasmids and chromosomal markers

  7. Biochemical Analysis of Recombinant AlkJ from Pseudomonas putida Reveals a Membrane-Associated, Flavin Adenine Dinucleotide-Dependent Dehydrogenase Suitable for the Biosynthetic Production of Aliphatic Aldehydes

    OpenAIRE

    Kirmair, Ludwig; Skerra, Arne

    2014-01-01

    The noncanonical alcohol dehydrogenase AlkJ is encoded on the alkane-metabolizing alk operon of the mesophilic bacterium Pseudomonas putida GPo1. To gain insight into the enzymology of AlkJ, we have produced the recombinant protein in Escherichia coli and purified it to homogeneity using His6 tag affinity and size exclusion chromatography (SEC). Despite synthesis in the cytoplasm, AlkJ was associated with the bacterial cell membrane, and solubilization with n-dodecyl-β-d-maltoside was necessa...

  8. In situ biosurfactant production and hydrocarbon removal by Pseudomonas putida CB-100 in bioaugmented and biostimulated oil-contaminated soil

    Directory of Open Access Journals (Sweden)

    Martínez-Toledo Ángeles

    2013-01-01

    Full Text Available In situ biosurfactant (rhamnolipid production by Pseudomonas putida CB-100 was achieved during a bioaugmented and biostimulated treatment to remove hydrocarbons from aged contaminated soil from oil well drilling operations. Rhamnolipid production and contaminant removal were determined for several treatments of irradiated and non-irradiated soils: nutrient addition (nitrogen and phosphorus, P. putida addition, and addition of both (P. putida and nutrients. The results were compared against a control treatment that consisted of adding only sterilized water to the soils. In treatment with native microorganisms (non-irradiated soils supplemented with P. putida, the removal of total petroleum hydrocarbons (TPH was 40.6%, the rhamnolipid production was 1.54 mg/kg, and a surface tension of 64 mN/m was observed as well as a negative correlation (R = -0.54; p < 0.019 between TPH concentration (mg/kg and surface tension (mN/m, When both bacteria and nutrients were involved, TPH levels were lowered to 33.7%, and biosurfactant production and surface tension were 2.03 mg/kg and 67.3 mN/m, respectively. In irradiated soil treated with P. putida, TPH removal was 24.5% with rhamnolipid generation of 1.79 mg/kg and 65.6 mN/m of surface tension, and a correlation between bacterial growth and biosurfactant production (R = -0.64; p < 0.009 was observed. When the nutrients and P. putida were added, TPH removal was 61.1%, 1.85 mg/kg of biosurfactants were produced, and the surface tension was 55.6 mN/m. In summary, in irradiated and non-irradiated soils, in situ rhamnolipid production by P. putida enhanced TPH decontamination of the soil.

  9. The Role of CzcRS Two-Component Systems in the Heavy Metal Resistance of Pseudomonas putida X4

    Directory of Open Access Journals (Sweden)

    Pulin Liu

    2015-07-01

    Full Text Available The role of different czcRS genes in metal resistance and the cross-link between czcRS and czcCBA in Pseudomonas putida X4 were studied to advance understanding of the mechanisms by which P. putida copes with metal stress. Similar to P. putida KT2440, two complete czcRS1 and czcRS2 two-component systems, as well as a czcR3 without the corresponding sensing component were amplified in P. putida X4. The histidine kinase genes czcS1 and czcS2 were inactivated and fused to lacZ by homologous recombination. The lacZ fusion assay revealed that Cd2+ and Zn2+ caused a decrease in the transcription of czcRS1, whereas Cd2+ treatment enhanced the transcription of czcRS2. The mutation of different czcRSs showed that all czcRSs are necessary to facilitate full metal resistance in P. putida X4. A putative gene just downstream of czcR3 is related to metal ion resistance, and its transcription was activated by Zn2+. Data from quantitative real-time polymerase chain reaction (qRT-PCR strongly suggested that czcRSs regulate the expression of czcCBA, and a cross-link exists between different czcRSs.

  10. Integrated foam fractionation for heterologous rhamnolipid production with recombinant Pseudomonas putida in a bioreactor.

    Science.gov (United States)

    Beuker, Janina; Steier, Anke; Wittgens, Andreas; Rosenau, Frank; Henkel, Marius; Hausmann, Rudolf

    2016-03-01

    Heterologeous production of rhamnolipids in Pseudomonas putida is characterized by advantages of a non-pathogenic host and avoidance of the native quorum sensing regulation in Pseudomonas aeruginosa. Yet, downstream processing is a major problem in rhamnolipid production and increases in complexity at low rhamnolipid titers and when using chemical foam control. This leaves the necessity of a simple concentrating and purification method. Foam fractionation is an elegant method for in situ product removal when producing microbial surfactants. However, up to now in situ foam fractionation is nearly exclusively reported for the production of surfactin with Bacillus subtilis. So far no cultivation integrated foam fractionation process for rhamnolipid production has been reported. This is probably due to excessive bacterial foam enrichment in that system. In this article a simple integrated foam fractionation process is reported for heterologous rhamnolipid production in a bioreactor with easily manageable bacterial foam enrichments. Rhamnolipids were highly concentrated in the foam during the cultivation process with enrichment factors up to 200. The described process was evaluated at different pH, media compositions and temperatures. Foam fractionation processes were characterized by calculating procedural parameter including rhamnolipid and bacterial enrichment, rhamnolipid recovery, YX/S, YP/X, and specific as well as volumetric productivities. Comparing foam fractionation parameters of the rhamnolipid process with the surfactin process a high effectiveness of the integrated foam fractionation for rhamnolipid production was demonstrated. PMID:26860613

  11. ISOLATION AND IDENTIFICATION OF A THERMOTOLERANT PLANT GROWTH PROMOTING PSEUDOMONAS PUTIDA PRODUCING TREHALOSE SYNTHASE

    Directory of Open Access Journals (Sweden)

    Ali Sk.Z.

    2013-08-01

    Full Text Available A thermotolerant plant growth promoting Pseudomonas isolate growing at 40oC producing trehalose synthase (TreS was isolated from rhizosphere soil under semi arid conditions of India. Trehalose synthase was extracted; purified and enzymatic activity was examined at various temperatures and pH. The optimum temperature and pH was 38oC and pH 7.5 and the activity declined at above or below the optimum pH and temperature. The enzyme was active on maltose and trehalose among saccharides tested. The enzyme had a higher catalytic activity for maltose with a trehalose yield of 72% than for trehalose where 30% yield of maltose was achieved, indicating maltose as preferred substrate. The isolate showed multiple plant growth promoting traits (indole acetic acid (IAA, phosphate solubilization, siderophore and ammonia both at ambient (28oC and high temperature (40oC. Based on phenotypic and 16SrRNA analysis the isolate was identified as Pseudomonas putida (Accession No. GU396283.

  12. Surface display of monkey metallothionein {alpha} tandem repeats and EGFP fusion protein on Pseudomonas putida X4 for biosorption and detection of cadmium

    Energy Technology Data Exchange (ETDEWEB)

    He, Xiaochuan; Chen, Wenli; Huang, Qiaoyun [Huazhong Agricultural Univ., Wuhan (China). State Key Lab. of Agricultural Microbiology

    2012-09-15

    Monkey metallothionein {alpha} domain tandem repeats (4mMT{alpha}), which exhibit high cadmium affinity, have been displayed for the first time on the surface of a bacterium using ice nucleation protein N-domain (inaXN) protein from the Xanthomonas campestris pv (ACCC - 10049) as an anchoring motif. The shuttle vector pIME, which codes for INAXN-4mMT{alpha}-EGFP fusion, was constructed and used to target 4mMT{alpha} and EGFP on the surface of Pseudomonas putida X4 (CCTCC - 209319). The surface location of the INAXN-4mMT{alpha}-EGFP fusion was further verified by western blot analysis and immunofluorescence microscopy. The growth of X4 showed resistance to cadmium presence. The presence of surface-exposed 4mMT{alpha} on the engineered strains was four times higher than that of the wild-type X4. The Cd{sup 2+} accumulation by X4/pIME was not only four times greater than that of the original host bacterial cells but was also remarkably unaffected by the presence of Cu{sup 2+} and Zn{sup 2+}. Moreover, the surface-engineered strains could effectively bind Cd{sup 2+} under a wide range of pH levels, from 4 to 7. P. putida X4/pIME with surface-expressed 4mMT{alpha}-EGFP had twice the cadmium binding capacity as well as 1.4 times the fluorescence as the cytoplasmic 4mMTa-EGFP. These results suggest that P. putida X4 expressing 4mMT{alpha}-EGFP with the INAXN anchor motif on the surface would be a useful tool for the remediation and biodetection of environmental cadmium contaminants. (orig.)

  13. Production and characterization of a recombinant single-chain antibody (scFv) for tracing the σ54 factor of Pseudomonas putida.

    Science.gov (United States)

    Jurado, Paola; Fernández, Luis Angel; de Lorenzo, Víctor

    2012-07-31

    The number of alternative sigma factor molecules per bacterial cell determines either stochasticity or evenness of transcription of cognate promoters. An approach for examining the abundance of sigmas in any sample of bacterial origin is explained here which relies on the production of a recombinant highly specific, high-affinity single-chain variable Fv domain (scFv) targeted towards unique protein sites of the factor. Purposely, a super-binder scFv recognizing a distinct epitope of the less abundant sigma σ(54) of Pseudomonas putida (also known as σ(N)) was obtained and its properties examined in detail. To this end, an scFv library was generated from mRNA extracted from lymphocytes of mice immunized with the purified σ(54) protein of this bacterium. The library was displayed on a phage system and subjected to various rounds of panning with purified σ(54) for capturing extreme binders. The resulting high-affinity anti-σ(54) phage antibody (Phab) clone named C2 strongly attached a small region located between positions 172 and 183 of the primary amino acid sequence of σ(54) that overlaps its core RNA polymerase-binding region. The purified scFv-C2 detected minute amounts of σ(54) in whole cell protein extracts not only of P. putida but also Escherichia coli cells and putatively in other bacteria as well. The affinity constant of the purified antibody was measured by surface plasmon resonance (SPR) and found to have a K(D) (k(off)/k(on)) in the range of 2×10(-9)M. The considerable affinity and specificity of this recombinant antibody makes it a tool of choice for quantitative studies on gene expression of σ(54)-dependent promoters in P. putida and other Gram-negative bacteria. PMID:22206981

  14. Crystallization and preliminary X-ray diffraction analysis of the azoreductase PpAzoR from Pseudomonas putida MET94

    International Nuclear Information System (INIS)

    PpAzoR, an FMN-dependent NADPH azoreductase from Pseudomonas putida MET94, has been crystallized using the sitting-drop vapour-diffusion technique. PpAzoR, an FMN-dependent NADPH azoreductase from Pseudomonas putida MET94, has been crystallized using the sitting-drop vapour-diffusion technique. The crystals diffracted to 1.6 Å resolution using synchrotron radiation and belonged to the orthorhombic space group F222, with unit-cell parameters a = 72.1, b = 95.5, c = 146.1 Å. Data sets were collected from the native protein to 2.2 Å resolution using in-house equipment and to 1.6 Å resolution using synchrotron radiation and the three-dimensional structure was determined by the molecular-replacement method

  15. Biotransformation of Hydroxylaminobenzene and Aminophenol by Pseudomonas putida 2NP8 Cells Grown in the Presence of 3-Nitrophenol

    OpenAIRE

    Zhao, Jian-Shen; Singh, Ajay; Huang, Xiao-Dong; Ward, Owen P.

    2000-01-01

    Biotransformation products of hydroxylaminobenzene and aminophenol produced by 3-nitrophenol-grown cells of Pseudomonas putida 2NP8, a strain grown on 2- and 3-nitrophenol, were characterized. Ammonia, 2-aminophenol, 4-aminophenol, 4-benzoquinone, N-acetyl-4-aminophenol, N-acetyl-2-aminophenol, 2-aminophenoxazine-3-one, 4-hydroquinone, and catechol were produced from hydroxylaminobenzene. Ammonia, N-acetyl-2-aminophenol, and 2-aminophenoxazine-3-one were produced from 2-aminophenol. All of th...

  16. Genetic organization and transcriptional analysis of a major gene cluster involved in siderophore biosynthesis in Pseudomonas putida WCS358.

    OpenAIRE

    Marugg, J. D.; Nielander, H.B.; Horrevoets, A J; Van Megen, I; van Genderen, I; Weisbeek, P.J.

    1988-01-01

    In iron-limited environments, the plant-growth-stimulating Pseudomonas putida WCS358 produces a yellow-green fluorescent siderophore called pseudobactin 358. The transcriptional organization and the iron-regulated expression of a major gene cluster involved in the biosynthesis and transport of pseudobactin 358 were analyzed in detail. The cluster comprises a region with a minimum length of 33.5 kilobases and contains at least five transcriptional units, of which some are relatively large. The...

  17. Regulation of enzymes of the 3,5-xylenol-degradative pathway in Pseudomonas putida: evidence for a plasmid.

    OpenAIRE

    Hopper, D. J.; Kemp, P D

    1980-01-01

    Constitutive synthesis of enzymes responsible for methyl group oxidation in 3,5-xylenol degradation and an associated p-cresol methylhydroxylase in Pseudomonas putida NCIB 9869 was shown by their retention at high specific activities in cells transferred from 3,5-xylenol medium to glutamate medium. The specific activities of other enzymes of the 3,5-xylenol pathway declined upon removal of aromatic substrate, consistent with their inducible control. Specific activities of the methyl-oxidizing...

  18. Stability of a Pseudomonas putida KT2440 Bacteriophage-Carried Genomic Island and Its Impact on Rhizosphere Fitness

    OpenAIRE

    Quesada, José Miguel; Soriano, María Isabel; Espinosa-Urgel, Manuel

    2012-01-01

    The stability of seven genomic islands of Pseudomonas putida KT2440 with predicted potential for mobilization was studied in bacterial populations associated with the rhizosphere of corn plants by multiplex PCR. DNA rearrangements were detected for only one of them (GI28), which was lost at high frequency. This genomic island of 39.4 kb, with 53 open reading frames, shows the characteristic organization of genes belonging to tailed phages. We present evidence indicating that it corresponds to...

  19. Proteomics reveals a core molecular response of Pseudomonas putida F1 to acute chromate challenge

    Directory of Open Access Journals (Sweden)

    McCarthy Andrea T

    2010-05-01

    Full Text Available Abstract Background Pseudomonas putida is a model organism for bioremediation because of its remarkable metabolic versatility, extensive biodegradative functions, and ubiquity in contaminated soil environments. To further the understanding of molecular pathways responding to the heavy metal chromium(VI [Cr(VI], the proteome of aerobically grown, Cr(VI-stressed P. putida strain F1 was characterized within the context of two disparate nutritional environments: rich (LB media and minimal (M9L media containing lactate as the sole carbon source. Results Growth studies demonstrated that F1 sensitivity to Cr(VI was impacted substantially by nutrient conditions, with a carbon-source-dependent hierarchy (lactate > glucose >> acetate observed in minimal media. Two-dimensional HPLC-MS/MS was employed to identify differential proteome profiles generated in response to 1 mM chromate under LB and M9L growth conditions. The immediate response to Cr(VI in LB-grown cells was up-regulation of proteins involved in inorganic ion transport, secondary metabolite biosynthesis and catabolism, and amino acid metabolism. By contrast, the chromate-responsive proteome derived under defined minimal growth conditions was characterized predominantly by up-regulated proteins related to cell envelope biogenesis, inorganic ion transport, and motility. TonB-dependent siderophore receptors involved in ferric iron acquisition and amino acid adenylation domains characterized up-regulated systems under LB-Cr(VI conditions, while DNA repair proteins and systems scavenging sulfur from alternative sources (e.g., aliphatic sulfonates tended to predominate the up-regulated proteome profile obtained under M9L-Cr(VI conditions. Conclusions Comparative analysis indicated that the core molecular response to chromate, irrespective of the nutritional conditions tested, comprised seven up-regulated proteins belonging to six different functional categories including transcription, inorganic ion

  20. Isolation of a strain of Pseudomonas putida capable of metabolizing anionic detergent sodium dodecyl sulfate (SDS

    Directory of Open Access Journals (Sweden)

    A Kumar

    2011-05-01

    Full Text Available Background and objectives: Sodium Dodecyl Sulfate (SDS is one of the most widely used anionic detergents. The present study deals with isolation and identification of SDS-degrading bacteria from a detergent contaminated pond situated in Varanasi city, India."nMaterials and Methods: Employing enrichment technique in minimal medium (PBM, SDS-degrading bacteria were isolated from pond water sample. Rate of degradation of SDS was studied in liquid PBM and also degradation of different concentrations of SDS was also studied to find out maximum concentration of SDS degraded by the potent isolates. Alkyl sulfatase activity (key enzyme in SDS degradation was estimated in crude cell extracts and multiplicity of alkyl sulfatase was studied by Native PAGE Zymography. The potent isolate was identified by 16S rRNA sequence analysis."nResults: Using enrichment technique in minimal medium containing SDS as a sole carbon source, initially three SDS degrading isolates were recovered. However, only one isolate, SP3, was found to be an efficient degrader of SDS. It was observed that this strain could completely metabolize 0.1% SDS in 16 h, 0.2% SDS in 20 h and 0.3% SDS in 24 h of incubation. Specific activity of alkyl sulfatase was 0.087±0.004 μmol SDS/mg protein/min and Native PAGE Zymography showed presence of alkyl sulfatase of Rf value of 0.21. This isolate was identified as Pseudomonas putida strain SP3."nConclusion: This is the report of isolation of SDS-degrading strain of P. putida, which shows high rate of SDS degradation and can degrade up to 0.3% SDS. It appears that this isolate can be exploited for bioremediation of this detergent from water systems.

  1. The Regulation of para-Nitrophenol Degradation in Pseudomonas putida DLL-E4

    Science.gov (United States)

    Chen, Qiongzhen; Tu, Hui; Luo, Xue; Zhang, Biying; Huang, Fei; Li, Zhoukun; Wang, Jue; Shen, Wenjing; Wu, Jiale; Cui, Zhongli

    2016-01-01

    Pseudomonas putida DLL-E4 can efficiently degrade para-nitrophenol and its intermediate metabolite hydroquinone. The regulation of para-nitrophenol degradation was studied, and PNP induced a global change in the transcriptome of P. putida DLL-E4. When grown on PNP, the wild-type strain exhibited significant downregulation of 2912 genes and upregulation of 845 genes, whereas 2927 genes were downregulated and 891 genes upregulated in a pnpR-deleted strain. Genes related to two non-coding RNAs (ins1 and ins2), para-nitrophenol metabolism, the tricarboxylic acid cycle, the outer membrane porin OprB, glucose dehydrogenase Gcd, and carbon catabolite repression were significantly upregulated when cells were grown on para-nitrophenol plus glucose. pnpA, pnpR, pnpC1C2DECX1X2, and pnpR1 are key genes in para-nitrophenol degradation, whereas pnpAb and pnpC1bC2bDbEbCbX1bX2b have lost the ability to degrade para-nitrophenol. Multiple components including transcriptional regulators and other unknown factors regulate para-nitrophenol degradation, and the transcriptional regulation of para-nitrophenol degradation is complex. Glucose utilization was enhanced at early stages of para-nitrophenol supplementation. However, it was inhibited after the total consumption of para-nitrophenol. The addition of glucose led to a significant enhancement in para-nitrophenol degradation and up-regulation in the expression of genes involved in para-nitrophenol degradation and carbon catabolite repression (CCR). It seemed that para-nitrophenol degradation can be regulated by CCR, and relief of CCR might contribute to enhanced para-nitrophenol degradation. In brief, the regulation of para-nitrophenol degradation seems to be controlled by multiple factors and requires further study. PMID:27191401

  2. Potential of Pseudomonas putida PCI2 for the Protection of Tomato Plants Against Fungal Pathogens.

    Science.gov (United States)

    Pastor, Nicolás; Masciarelli, Oscar; Fischer, Sonia; Luna, Virginia; Rovera, Marisa

    2016-09-01

    Tomato is one of the most economically attractive vegetable crops due to its high yields. Diseases cause significant losses in tomato production worldwide. We carried out Polymerase Chain Reaction studies to detect the presence of genes encoding antifungal compounds in the DNA of Pseudomonas putida strain PCI2. We also used liquid chromatography-electrospray tandem mass spectrometry to detect and quantify the production of compounds that increase the resistance of plants to diseases from culture supernatants of PCI2. In addition, we investigated the presence of 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase in PCI2. Finally, PCI2 was used for inoculation of tomato seeds to study its potential biocontrol activity against Fusarium oxysporum MR193. The obtained results showed that no fragments for the encoding genes of hydrogen cyanide, pyoluteorin, 2,4-diacetylphloroglucinol, pyrrolnitrin, or phenazine-1-carboxylic acid were amplified from the DNA of PCI2. On the other hand, PCI2 produced salicylic acid and jasmonic acid in Luria-Bertani medium and grew in a culture medium containing ACC as the sole nitrogen source. We observed a reduction in disease incidence from 53.33 % in the pathogen control to 30 % in tomato plants pre-inoculated with PCI2 as well as increases in shoot and root dry weights in inoculated plants, as compared to the pathogenicity control. This study suggests that inoculation of tomato seeds with P. putida PCI2 increases the resistance of plants to root rot caused by F. oxysporum and that PCI2 produces compounds that may be involved at different levels in increasing such resistance. Thus, PCI2 could represent a non-contaminating management strategy potentially applicable in vegetable crops such as tomato. PMID:27246499

  3. The Regulation of para-Nitrophenol Degradation in Pseudomonas putida DLL-E4.

    Directory of Open Access Journals (Sweden)

    Qiongzhen Chen

    Full Text Available Pseudomonas putida DLL-E4 can efficiently degrade para-nitrophenol and its intermediate metabolite hydroquinone. The regulation of para-nitrophenol degradation was studied, and PNP induced a global change in the transcriptome of P. putida DLL-E4. When grown on PNP, the wild-type strain exhibited significant downregulation of 2912 genes and upregulation of 845 genes, whereas 2927 genes were downregulated and 891 genes upregulated in a pnpR-deleted strain. Genes related to two non-coding RNAs (ins1 and ins2, para-nitrophenol metabolism, the tricarboxylic acid cycle, the outer membrane porin OprB, glucose dehydrogenase Gcd, and carbon catabolite repression were significantly upregulated when cells were grown on para-nitrophenol plus glucose. pnpA, pnpR, pnpC1C2DECX1X2, and pnpR1 are key genes in para-nitrophenol degradation, whereas pnpAb and pnpC1bC2bDbEbCbX1bX2b have lost the ability to degrade para-nitrophenol. Multiple components including transcriptional regulators and other unknown factors regulate para-nitrophenol degradation, and the transcriptional regulation of para-nitrophenol degradation is complex. Glucose utilization was enhanced at early stages of para-nitrophenol supplementation. However, it was inhibited after the total consumption of para-nitrophenol. The addition of glucose led to a significant enhancement in para-nitrophenol degradation and up-regulation in the expression of genes involved in para-nitrophenol degradation and carbon catabolite repression (CCR. It seemed that para-nitrophenol degradation can be regulated by CCR, and relief of CCR might contribute to enhanced para-nitrophenol degradation. In brief, the regulation of para-nitrophenol degradation seems to be controlled by multiple factors and requires further study.

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

    Energy Technology Data Exchange (ETDEWEB)

    Daniel P. Molloy

    2004-02-24

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

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

    DEFF Research Database (Denmark)

    Thuesen, Marianne Hallberg; Nørgaard, Allan; Hansen, Anne Merete; Caspersen, Michael Bjerg; Christensen, Hans Erik Mølager

    2003-01-01

    The gene of the di-heme protein cytochrome c(4) from Pseudomonas stutzeri was expressed in Pseudomonas putida. High-yield expression of the protein was achieved by high-cell-density fed-batch cultivation using an exponential glucose feeding strategy. The recombinant cytochrome c(4) protein was...... cytochrome c(4). Furthermore, the calculated and experimentally determined molecular masses of recombinant cytochrome c(4) were identical. Biochemical characterization of both wild-type and mutant derivatives of the protein will be greatly enhanced and facilitated by the described high-yield fermentation and...

  6. Interesterification of butter fat by partially purified extracellular lipases from Pseudomonas putida, Aspergillus niger and Rhizopus oryzae.

    Science.gov (United States)

    Pabai, F; Kermasha, S; Morin, A

    1995-11-01

    Three extracellular lipases were produced by batch fermentation of Pseudomonas putida ATCC 795, Aspergillus niger CBS 131.52 and Rhizopus oryzae ATCC 34612 during the late phase of growth, at 72, 96 and 96 h, respectively. The lipases were partially purified by (NH4)2SO4 fractionation. The lipase of P. putida was optimal at pH 8.0 whereas those from A. niger and R. oryzae were optimal at pH 7.5. The A. niger lipase had the lowest V max value (0.51×10(-3) U/min) and R. oryzae the highest (1.86×10(-3) U/min). The K m values for P. putida, A. niger and R. oryzae lipases were 1.18, 0.97, and 0.98 mg/ml, respectively. Native PAGE of the partially-purified lipase extracts showed two to four major bands. The interesterification of butter fat by A. niger lipase decreased the water activity as well as the hydrolytic activity. The A. niger lipase had the highest interesterification yield value (26%) and the R. oryzae lipase the lowest (4%). In addition, A. niger lipase exhibited the highest decrease (17%) in long-chain hypercholesterolemic fatty acids (C12:0, C14:0 and C16:0) at the sn-2-position; the P. putida lipase demonstrated the least favourable changes in specificity at the same position. PMID:24415019

  7. The alternative sigma factor, sigmaS, affects polyhydroxyalkanoate metabolism in Pseudomonas putida.

    Science.gov (United States)

    Raiger-Iustman, Laura J; Ruiz, Jimena A

    2008-07-01

    To determine whether the stationary sigma factor, sigma(S), influences polyhydroxyalkanoate metabolism in Pseudomonas putida KT2440, an rpoS-negative mutant was constructed to evaluate polyhydroxyalkanoate accumulation and expression of a translational fusion to the promoter region of the genes that code for polyhydroxyalkanoate synthase 1 (phaC1) and polyhydroxyalkanoate depolymerase (phaZ). By comparison with the wild-type, the rpoS mutant showed a higher polyhydroxyalkanoate degradation rate and increased expression of the translational fusion during the stationary growth phase. These results suggest that sigma(S) might control the genes involved in polyhydroxyalkanoate metabolism, possibly in an indirect manner. In addition, survival and oxidative stress assays performed under polyhydroxyalkanoate- and nonpolyhydroxyalkanoate- accumulating conditions demonstrated that the accumulated polyhydroxyalkanoate increased the survival and stress tolerance of the rpoS mutant. According to this, polyhydroxyalkanoate accumulation would help cells to overcome the adverse conditions encountered during the stationary phase in the strain that lacks RpoS. PMID:18498401

  8. Effect of silver nanoparticles on Pseudomonas putida biofilms at different stages of maturity

    International Nuclear Information System (INIS)

    Highlights: • Biofilm stages in static batch conditions were similar to dynamic conditions. • Expression of csgA gene increased earlier than alg8 gene in biofilm maturation. • AgNPs had higher effect on less mature biofilms. • Removal of extracellular polymeric substance made biofilms susceptible to AgNPs. - Abstract: This study determined the effect of silver nanoparticles (AgNPs) on Pseudomonas putida KT2440 biofilms at different stages of maturity. Three biofilm stages (1–3, representing early to late stages of development) were identified from bacterial adenosine triphosphate (ATP) activity under static (96-well plate) and dynamic conditions (Center for Disease Control and Prevention biofilm reactor). Extracellular polymeric substance (EPS) levels, measured using crystal violet and total carbohydrate assays, and expression of the EPS-associated genes, csgA and alg8, supported the conclusion that biofilms at later stages were older than those at earlier stages. More mature biofilms (stages 2 and 3) showed little to no reduction in ATP activity following exposure to AgNPs. In contrast, the same treatment reduced ATP activity by more than 90% in the less mature stage 1 biofilms. Regardless of maturity, biofilms with EPS stripped off were more susceptible to AgNPs than controls with intact EPS, demonstrating that EPS is critical for biofilm tolerance of AgNPs. The findings from this study show that stage of maturity is an important factor to consider when studying effect of AgNPs on biofilms

  9. Synergistic effect of Pseudomonas putida and Bacillus amyloliquefaciens ameliorates drought stress in chickpea (Cicer arietinum L.).

    Science.gov (United States)

    Kumar, Manoj; Mishra, Sankalp; Dixit, Vijaykant; Kumar, Manoj; Agarwal, Lalit; Chauhan, Puneet Singh; Nautiyal, Chandra Shekhar

    2016-01-01

    Two plant growth promoting rhizobacteria (PGPR) Pseudomonas putida NBRIRA and Bacillus amyloliquefaciens NBRISN13 with ability to tolerate abiotic stress along with multiple PGP traits like ACC deaminase activity, minerals solubilisation, hormones production, biofilm formation, siderophore activity were evaluated for their synergistic effect to ameliorate drought stress in chickpea. Earlier we have reported both the strains individually for their PGP attributes and stress amelioration in host plants. The present study explains in detail the possibilities and benefits of utilizing these 2 PGPR in consortium for improving the chickpea growth under control and drought stressed condition. In vitro results clearly demonstrate that both the PGPR strains are compatible to each other and their synergistic growth enhances the PGP attributes. Greenhouse experiments were conducted to evaluate the effect of inoculation of both strains individually and consortia in drought tolerant and sensitive cultivars (BG362 and P1003). The growth parameters were observed significantly higher in consortium as compared to individual PGPR. Colonization of both PGPR in chickpea rhizosphere has been visualized by using gfp labeling. Apart from growth parameters, defense enzymes, soil enzymes and microbial diversity were significantly modulated in individually PGPR and in consortia inoculated plants. Negative effects of drought stress has been ameliorated and apparently seen by higher biomass and reversal of stress indicators in chickpea cultivars treated with PGPR individually or in consortia. Findings from the present study demonstrate that synergistic application has better potential to improve plant growth promotion under drought stress conditions. PMID:26362119

  10. Effect of silver nanoparticles on Pseudomonas putida biofilms at different stages of maturity

    Energy Technology Data Exchange (ETDEWEB)

    Thuptimdang, Pumis, E-mail: pumis.th@gmail.com [International Program in Hazardous Substance and Environmental Management, Graduate School, Chulalongkorn University, Bangkok 10330 (Thailand); Center of Excellence on Hazardous Substance Management, Bangkok 10330 (Thailand); Limpiyakorn, Tawan, E-mail: tawan.l@chula.ac.th [Center of Excellence on Hazardous Substance Management, Bangkok 10330 (Thailand); Department of Environmental Engineering, Chulalongkorn University, Bangkok 10330 (Thailand); Research Unit Control of Emerging Micropollutants in Environment, Chulalongkorn University, Bangkok 10330 (Thailand); McEvoy, John, E-mail: john.mcevoy@ndsu.edu [Department of Veterinary and Microbiological Sciences, North Dakota State University, Fargo, ND 58108 (United States); Prüß, Birgit M., E-mail: birgit.pruess@ndsu.edu [Department of Veterinary and Microbiological Sciences, North Dakota State University, Fargo, ND 58108 (United States); Khan, Eakalak, E-mail: eakalak.khan@ndsu.edu [Department of Civil and Environmental Engineering, North Dakota State University, Fargo, ND 58108 (United States)

    2015-06-15

    Highlights: • Biofilm stages in static batch conditions were similar to dynamic conditions. • Expression of csgA gene increased earlier than alg8 gene in biofilm maturation. • AgNPs had higher effect on less mature biofilms. • Removal of extracellular polymeric substance made biofilms susceptible to AgNPs. - Abstract: This study determined the effect of silver nanoparticles (AgNPs) on Pseudomonas putida KT2440 biofilms at different stages of maturity. Three biofilm stages (1–3, representing early to late stages of development) were identified from bacterial adenosine triphosphate (ATP) activity under static (96-well plate) and dynamic conditions (Center for Disease Control and Prevention biofilm reactor). Extracellular polymeric substance (EPS) levels, measured using crystal violet and total carbohydrate assays, and expression of the EPS-associated genes, csgA and alg8, supported the conclusion that biofilms at later stages were older than those at earlier stages. More mature biofilms (stages 2 and 3) showed little to no reduction in ATP activity following exposure to AgNPs. In contrast, the same treatment reduced ATP activity by more than 90% in the less mature stage 1 biofilms. Regardless of maturity, biofilms with EPS stripped off were more susceptible to AgNPs than controls with intact EPS, demonstrating that EPS is critical for biofilm tolerance of AgNPs. The findings from this study show that stage of maturity is an important factor to consider when studying effect of AgNPs on biofilms.

  11. Performance and Kinetic Evaluation of Ethyl Acetate Biodegradation in a Biofilter Using Pseudomonas Putida

    Directory of Open Access Journals (Sweden)

    Hossein Zare

    2012-01-01

    Full Text Available Biodegradation of ethyl acetate in batch and continuous cultures was investigated. Pseudomonas putida was selected as a biological agent to biodegrade ethyl acetate. In batch experiment, biodegradation of ethyl acetate was performed in the range of 25-35°C. Walnut shells treated with alkaline solution as natural packing materials provided an appropriate environment for the growth and immobilization of microorganisms. The active biofilm was fully established on the surface of natural packing material. In the early stage, experiments were performed at Empty Bed Resistance Time (EBRT of 60 s. Maximum removal efficiency of 99% was achieved at inlet concentrations lower than 430 ppm of ethyl acetate. The removal efficiency dropped to 80% with an increase of inlet concentration of ethyl acetate. In order to enhance the removal efficiency, the EBRT was increased from 60 to 75 s. At EBRT of 75 s, the removal efficiency was maintained above 80% even though the inlet concentration increased to 5150 ppm. Michaelis-Menten and Logistic models were perfectly fitted to experimental data. In addition, the kinetic parameters of presented models were defined

  12. Evaluation of Zosteric Acid for Mitigating Biofilm Formation of Pseudomonas putida Isolated from a Membrane Bioreactor System

    Directory of Open Access Journals (Sweden)

    Andrea Polo

    2014-05-01

    Full Text Available This study provides data to define an efficient biocide-free strategy based on zosteric acid to counteract biofilm formation on the membranes of submerged bioreactor system plants. 16S rRNA gene phylogenetic analysis showed that gammaproteobacteria was the prevalent taxa on fouled membranes of an Italian wastewater plant. Pseudomonas was the prevalent genus among the cultivable membrane-fouler bacteria and Pseudomonas putida was selected as the target microorganism to test the efficacy of the antifoulant. Zosteric acid was not a source of carbon and energy for P. putida cells and, at 200 mg/L, it caused a reduction of bacterial coverage by 80%. Biofilm experiments confirmed the compound caused a significant decrease in biomass (−97% and thickness (−50%, and it induced a migration activity of the peritrichous flagellated P. putida over the polycarbonate surface not amenable to a biofilm phenotype. The low octanol-water partitioning coefficient and the high water solubility suggested a low bioaccumulation potential and the water compartment as its main environmental recipient and capacitor. Preliminary ecotoxicological tests did not highlight direct toxicity effects toward Daphnia magna. For green algae Pseudokirchneriella subcapitata an effect was observed at concentrations above 100 mg/L with a significant growth of protozoa that may be connected to a concurrent algal growth inhibition.

  13. Evaluation of Zosteric Acid for Mitigating Biofilm Formation of Pseudomonas putida Isolated from a Membrane Bioreactor System

    Science.gov (United States)

    Polo, Andrea; Foladori, Paola; Ponti, Benedetta; Bettinetti, Roberta; Gambino, Michela; Villa, Federica; Cappitelli, Francesca

    2014-01-01

    This study provides data to define an efficient biocide-free strategy based on zosteric acid to counteract biofilm formation on the membranes of submerged bioreactor system plants. 16S rRNA gene phylogenetic analysis showed that gammaproteobacteria was the prevalent taxa on fouled membranes of an Italian wastewater plant. Pseudomonas was the prevalent genus among the cultivable membrane-fouler bacteria and Pseudomonas putida was selected as the target microorganism to test the efficacy of the antifoulant. Zosteric acid was not a source of carbon and energy for P. putida cells and, at 200 mg/L, it caused a reduction of bacterial coverage by 80%. Biofilm experiments confirmed the compound caused a significant decrease in biomass (−97%) and thickness (−50%), and it induced a migration activity of the peritrichous flagellated P. putida over the polycarbonate surface not amenable to a biofilm phenotype. The low octanol-water partitioning coefficient and the high water solubility suggested a low bioaccumulation potential and the water compartment as its main environmental recipient and capacitor. Preliminary ecotoxicological tests did not highlight direct toxicity effects toward Daphnia magna. For green algae Pseudokirchneriella subcapitata an effect was observed at concentrations above 100 mg/L with a significant growth of protozoa that may be connected to a concurrent algal growth inhibition. PMID:24879523

  14. The impact of ColRS two-component system and TtgABC efflux pump on phenol tolerance of Pseudomonas putida becomes evident only in growing bacteria

    OpenAIRE

    Kivisaar Maia; Lilje Liisa; Ilves Heili; Putrinš Marta; Hõrak Rita

    2010-01-01

    Abstract Background We have recently found that Pseudomonas putida deficient in ColRS two-component system is sensitive to phenol and displays a serious defect on solid glucose medium where subpopulation of bacteria lyses. The latter phenotype is significantly enhanced by the presence of phenol in growth medium. Here, we focused on identification of factors affecting phenol tolerance of the colR-deficient P. putida. Results By using transposon mutagenesis approach we identified a set of pheno...

  15. Metabolism of Chlorotoluenes by Burkholderia sp. Strain PS12 and Toluene Dioxygenase of Pseudomonas putida F1: Evidence for Monooxygenation by Toluene and Chlorobenzene Dioxygenases

    OpenAIRE

    Lehning, A.; Fock, U.; Wittich, R.; Timmis, K N; Pieper, D.H.

    1997-01-01

    The degradation of toluene by Pseudomonas putida F1 and of chlorobenzenes by Burkholderia sp. strain PS12 is initiated by incorporation of dioxygen into the aromatic nucleus to form cis-dihydrodihydroxybenzenes. Toluene-grown cells of P. putida F1 and 3-chlorobenzoate-grown cells of Burkholderia sp. strain PS12 were found to monooxygenate the side chain of 2- and 3-chlorotoluene to the corresponding chlorobenzyl alcohols. Further metabolism of these products was slow, and the corresponding ch...

  16. Characterization and Two-Dimensional Crystallization of Membrane Component AlkB of the Medium-Chain Alkane Hydroxylase System from Pseudomonas putida GPo1

    OpenAIRE

    Alonso, Hernan; Roujeinikova, Anna

    2012-01-01

    The alkane hydroxylase system of Pseudomonas putida GPo1 allows it to use alkanes as the sole source of carbon and energy. Bacterial alkane hydroxylases have tremendous potential as biocatalysts for the stereo- and regioselective transformation of a wide range of chemically inert unreactive alkanes into valuable reactive chemical precursors. We have produced and characterized the first 2-dimensional crystals of the integral membrane component of the P. putida alkane hydroxylase system, the no...

  17. Genetic and functional characterization of the gene cluster directing the biosynthesis of putisolvin I and II in Pseudomonas putida strain PCL1445

    OpenAIRE

    Dubern, J.F.; Coppoolse, E.R.; Stiekema, W.J.; Bloemberg, G. V.

    2008-01-01

    Pseudomonas putida PCL1445 secretes two cyclic lipopeptides, putisolvin I and putisolvin II, which possess a surface-tension-reducing ability, and are able to inhibit biofilm formation and to break down biofilms of Pseudomonas species including Pseudomonas aeruginosa. The putisolvin synthetase gene cluster (pso) and its surrounding region were isolated, sequenced and characterized. Three genes, termed psoA, psoB and psoC, were identified and shown to be involved in putisolvin biosynthesis. Th...

  18. Colony morphology and transcriptome profiling of Pseudomonas putida KT2440 and its mutants deficient in alginate or all EPS synthesis under controlled matric potentials

    DEFF Research Database (Denmark)

    Gülez, Gamze; Altintas, Ali; Fazli, Mustafa;

    2014-01-01

    Pseudomonas putida is a versatile bacterial species adapted to soil and its fluctuations. Like many other species living in soil, P. putida often faces water limitation. Alginate, an exopolysaccharide (EPS) produced by P. putida, is known to create hydrated environments and alleviate the effect of...... different EPS components under mild water limitation. To create environmentally realistic water limited conditions as observed in soil, we used the Pressurized Porous Surface Model. Our main hypothesis was that under water limitation and in the absence of alginate other exopolysaccharides would be more...

  19. Draft Genome Sequences of Pseudomonas fluorescens Strains PA4C2 and PA3G8 and Pseudomonas putida PA14H7, Three Biocontrol Bacteria against Dickeya Phytopathogens

    OpenAIRE

    Cigna, Jérémy; Raoul des Essarts, Yannick; Mondy, Samuel; Hélias, Valérie; Beury-Cirou, Amélie; Faure, Denis

    2015-01-01

    Pseudomonas fluorescens strains PA4C2 and PA3G8 and Pseudomonas putida strain PA14H7 were isolated from potato rhizosphere and show an ability to inhibit the growth of Dickeya phytopathogens. Here, we report their draft genome sequences, which provide a basis for understanding the molecular mechanisms involved in antibiosis against Dickeya.

  20. Influence of oxygen transfer on Pseudomonas putida effects on growth rate and biodesulfurization capacity.

    Science.gov (United States)

    Escobar, S; Rodriguez, A; Gomez, E; Alcon, A; Santos, V E; Garcia-Ochoa, Felix

    2016-04-01

    The growth rate and desulfurization capacity accumulated by the cells during the growth of Pseudomonas putida KTH2 under different oxygen transfer conditions in a stirred and sparged tank bioreactor have been studied. Hydrodynamic conditions were changed using different agitation conditions. During the culture, several magnitudes associated to growth, such as the specific growth rate, the dissolved oxygen concentration and the carbon source consumption have been measured. Experimental results indicate that cultures are influenced by the fluid dynamic conditions into the bioreactor. An increase in the stirrer speed from 400 to 700 rpm has a positive influence on the cell growth rate. Nevertheless, the increase of agitation from 700 to 2000 rpm hardly has any influence on the growth rate. The effect of fluid dynamics on the cells development of the biodesulfurization (BDS) capacity of the cells during growth is different. The activities of the intracellular enzymes involved in the 4S pathway change with dissolved oxygen concentration. The enzyme activities have been evaluated in cells at several growth time and different hydrodynamic conditions. An increase of the agitation from 100 to 300 rpm has a positive influence on the development of the overall BDS capacity of the cells during growth. This capacity shows a decrease for higher stirrer speeds and the activity of the enzymes monooxygenases DszC and DszA decreases dramatically. The highest value of the activity of DszB enzyme was obtained with cells cultured at 100 rpm, while this activity decreases when the stirrer speed was increased higher than this value. PMID:26762940

  1. Antimicrobial activities of commercial nanoparticles against an environmental soil microbe, Pseudomonas putida KT2440

    Directory of Open Access Journals (Sweden)

    Huang Wenjie

    2009-06-01

    Full Text Available Abstract Background The release of heavy metal-containing nanoparticles (NP into the environment may be harmful to the efficacy of beneficial microbes that function in element cycling, pollutant degradation and plant growth. Nanoparticles of Ag, CuO and ZnO are of interest as antimicrobials against pathogenic bacteria. We demonstrate here their antimicrobial activity against the beneficial soil microbe, Pseudomonas putida KT2440. Results Toxicity was detected in a KT2440 construct possessing a plasmid bearing the luxAB reporter genes. "As manufactured" preparations of nano- Ag, -CuO and -ZnO caused rapid dose-dependent loss of light output in the biosensor. Cell death accompanied loss in Lux activity with treatments by nano-Ag and -CuO, but with -ZnO the treatments were bacteriostatic rather than bactericidal. Bulk equivalents of these products showed no inhibitory activity, indicating that particle size was determinant in activity. Flow Field-Flow Fractionation (FlFFF of an aqueous suspension of the nano-CuO and ZnO revealed a small proportion of 5 nm NP and aggregated particulates with sizes ranging between 70 nm and 300 nm; the majority portion of material was aggregated into particles larger than 300 nm in size. Thus within the commercial preparation there may be microbially active and inactive forms. Conclusion The "as-made" NP of Ag, CuO and ZnO have toxic effects on a beneficial soil microbe, leading to bactericidal or bacteriostatic effects depending on the NP employed. The lack of toxicity from bulk materials suggests that aggregation of the NP into larger particles, possibly by factors present in the environment may reduce their nontarget antimicrobial activity.

  2. New dye-decolorizing peroxidases from Bacillus subtilis and Pseudomonas putida MET94: towards biotechnological applications.

    Science.gov (United States)

    Santos, Ana; Mendes, Sónia; Brissos, Vânia; Martins, Lígia O

    2014-03-01

    This work provides spectroscopic, catalytic, and stability fingerprints of two new bacterial dye-decolorizing peroxidases (DyPs) from Bacillus subtilis (BsDyP) and Pseudomonas putida MET94 (PpDyP). DyPs are a family of microbial heme-containing peroxidases with wide substrate specificity, including high redox potential aromatic compounds such as synthetic dyes or phenolic and nonphenolic lignin units. The genes encoding BsDyP and PpDyP, belonging to subfamilies A and B, respectively, were cloned and heterologously expressed in Escherichia coli. The recombinant PpDyP is a 120-kDa homotetramer while BsDyP enzyme consists of a single 48-kDa monomer. The optimal pH of both enzymes is in the acidic range (pH 4-5). BsDyP has a bell-shape profile with optimum between 20 and 30 °C whereas PpDyP shows a peculiar flat and broad (10-30 °C) temperature profile. Anthraquinonic or azo dyes, phenolics, methoxylated aromatics, and also manganese and ferrous ions are substrates used by the enzymes. In general, PpDyP exhibits higher activities and accepts a wider scope of substrates than BsDyP; the spectroscopic data suggest distinct heme microenvironments in the two enzymes that might account for the distinctive catalytic behavior. However, the Bs enzyme with activity lasting for up to 53 h at 40 °C is more stable towards temperature or chemical denaturation than the PpDyP. The results of this work will guide future optimization of the biocatalytis towards their utilization in the fields of environmental or industrial biotechnology. PMID:23820555

  3. Functional Characterization of the Quorum Sensing Regulator RsaL in the Plant-Beneficial Strain Pseudomonas putida WCS358

    OpenAIRE

    Rampioni, Giordano; Bertani, Iris; Pillai, Cejoice Ramachandran; Venturi, Vittorio; Zennaro, Elisabetta; Leoni, Livia

    2012-01-01

    In many bacteria, quorum sensing (QS) systems rely on a signal receptor and a synthase producing N-acyl-homoserine lactone(s) as the signal molecule(s). In some species, the rsaL gene, located between the signal receptor and synthase genes, encodes a repressor limiting signal synthase expression and hence signal molecule production. Here we investigate the molecular mechanism of action of the RsaL protein in the plant growth-promoting rhizobacterium Pseudomonas putida WCS358 (RsaLWCS). In P. ...

  4. Metabolite profiling reveals abiotic stress tolerance in Tn5 mutant of Pseudomonas putida.

    Directory of Open Access Journals (Sweden)

    Vasvi Chaudhry

    Full Text Available Pseudomonas is an efficient plant growth-promoting rhizobacteria (PGPR; however, intolerance to drought and high temperature limit its application in agriculture as a bioinoculant. Transposon 5 (Tn5 mutagenesis was used to generate a stress tolerant mutant from a PGPR Pseudomonas putida NBRI1108 isolated from chickpea rhizosphere. A mutant NBRI1108T, selected after screening of nearly 10,000 transconjugants, exhibited significant tolerance towards high temperature and drought. Southern hybridization analysis of EcoRI and XhoI restricted genomic DNA of NBRI1108T confirmed that it had a single Tn5 insertion. The metabolic changes in the polar and non-polar extracts of NBRI1108 and NBRI1108T were examined using 1H, 31P nuclear magnetic resonance (NMR spectroscopy and gas chromatography-mass spectrometry (GC-MS. Thirty six chemically diverse metabolites consisting of amino acids, fatty acids and phospholipids were identified and quantified. Insertion of Tn5 influenced amino acid and phospholipid metabolism and resulted in significantly higher concentration of aspartic acid, glutamic acid, glycinebetaine, glycerophosphatidylcholine (GPC and putrescine in NBRI1108T as compared to that in NBRI1108. The concentration of glutamic acid, glycinebetaine and GPC increased by 34%, 95% and 100%, respectively in the NBRI1108T as compared to that in NBRI1108. High concentration of glycerophosphatidylethanolamine (GPE and undetected GPC in NBRI1108 indicates that biosynthesis of GPE may have taken place via the methylation pathway of phospholipid biosynthesis. However, high GPC and low GPE concentration in NBRI1108T suggest that methylation pathway and phosphatidylcholine synthase (PCS pathway of phospholipid biosynthesis are being followed in the NBRI1108T. Application of multivariate principal component analysis (PCA on the quantified metabolites revealed clear variations in NBRI1108 and NBRI1108T in polar and non-polar metabolites. Identification of abiotic

  5. Biosynthetic Origin of the Antibiotic Pseudopyronines A and B in Pseudomonas putida BW11M1.

    Science.gov (United States)

    Bauer, Judith S; Ghequire, Maarten G K; Nett, Markus; Josten, Michaele; Sahl, Hans-Georg; De Mot, René; Gross, Harald

    2015-11-01

    Within the framework of our effort to discover new antibiotics from pseudomonads, pseudopyronines A and B were isolated from the plant-derived Pseudomonas putida BW11M1. Pseudopyronines are 3,6-dialkyl-4-hydroxy-2-pyrones and displayed high in vitro activities against several human pathogens, and in our hands also towards the plant pathogen Pseudomonas savastanoi. Here, the biosynthesis of pseudopyronine B was studied by a combination of feeding experiments with isotopically labeled precursors, genomic sequence analysis, and gene deletion experiments. The studies resulted in the deduction of all acetate units and revealed that the biosynthesis of these α-pyrones occurs with a single PpyS-homologous ketosynthase. It fuses, with some substrate flexibility, a 3-oxo-fatty acid and a further unbranched saturated fatty acid, both of medium chain-length and provided by primary metabolism. PMID:26507104

  6. Biological production of hydroxylated aromatics: Optimization strategies for Pseudomonas putida S12

    OpenAIRE

    A. Verhoef

    2010-01-01

    To replace environmentally unfriendly petrochemical production processes, the demand for bio-based production of organic chemicals is increasing. This thesis focuses on the biological production of hydroxylated aromatics from renewable substrates by engineered P. putida S12 including several cases of strain improvement. Chapter 2 describes the construction of a P. putida S12 strain that produces p-hydroxybenzoate via the aromatic amino acid tyrosine. Previous research on biosynthesis of aroma...

  7. Nitrogen contribution proportion from soil, fertilizer and pseudomonas putida like in sorghum plantation on South Sumatra's inceptisols

    International Nuclear Information System (INIS)

    The proportion of N which absorbed either from natural source (soil), N-fertilizer or N sub.2-fixing microorganism on sorghum plantation in marginal alang-alang lands that group to inceptisol should be studied in securing the soil fertility. In this experiment, N contribution of those N sources was determined during vegetative stage of sorghum on three subgroup of south sumatera's inceptisols. A greenhouse experiment that arranged in randomized complete block design using 2 factorial split plot was carried out in IPB Bogor from May-December 1998. The observation was focused on partition of N contribution from the soil, N-fertilizer and Pseudomonas putida like(N sub.2-fixing microorganism) on total plant-content 4 and 8 weeks after plantations (WAP). N-partition from those N-sources was done based o A-value method. Sorghum was absorb larger proportion of N from soil(63,36%-48,83% on 4 WAP and 64,58 % on WAP) than from fertilizer and P.putida like on all of the soil subgroups. Soil-N absorption was highest on oxic dystropept. Pseudomonas putida like was not able to subtite soil-N and fertilizer-N in sufficient amount to vigorous plant growth particularly on typica humitropept and typic dystropept. The microorganism was only provide a small amount of N to sorghum on oxic dystropept (23,05-23,95 % on 4 WAP and 15,91-34,44 % on 8WAP). The increment of plant root surface area could be enhance in greater extent of plant-N absorption than N sub.2-fixation. Thus, plantation of marginal tolerant sorghum still need addition of N-fertilizer

  8. Genetic engineering of Pseudomonas putida KT2440 for rapid and high-yield production of vanillin from ferulic acid.

    Science.gov (United States)

    Graf, Nadja; Altenbuchner, Josef

    2014-01-01

    Vanillin is one of the most important flavoring agents used today. That is why many efforts have been made on biotechnological production from natural abundant substrates. In this work, the nonpathogenic Pseudomonas putida strain KT2440 was genetically optimized to convert ferulic acid to vanillin. Deletion of the vanillin dehydrogenase gene (vdh) was not sufficient to prevent vanillin degradation. Additional inactivation of a molybdate transporter, identified by transposon mutagenesis, led to a strain incapable to grow on vanillin as sole carbon source. The bioconversion was optimized by enhanced chromosomal expression of the structural genes for feruloyl-CoA synthetase (fcs) and enoyl-CoA hydratase/aldolase (ech) by introduction of the strong tac promoter system. Further genetic engineering led to high initial conversion rates and molar vanillin yields up to 86% within just 3 h accompanied with very low by-product levels. To our knowledge, this represents the highest productivity and molar vanillin yield gained with a Pseudomonas strain so far. Together with its high tolerance for ferulic acid, the developed, plasmid-free P. putida strain represents a promising candidate for the biotechnological production of vanillin. PMID:24136472

  9. Crystallization and crystallographic analysis of the ligand-binding domain of the Pseudomonas putida chemoreceptor McpS in complex with malate and succinate

    International Nuclear Information System (INIS)

    The crystallization of the ligand-binding domain of the methyl-accepting chemotaxis protein chemoreceptor McpS (McpS-LBD) is reported. Methyl-accepting chemotaxis proteins (MCPs) are transmembrane proteins that sense changes in environmental signals, generating a chemotactic response and regulating other cellular processes. MCPs are composed of two main domains: a ligand-binding domain (LBD) and a cytosolic signalling domain (CSD). Here, the crystallization of the LBD of the chemoreceptor McpS (McpS-LBD) is reported. McpS-LBD is responsible for sensing most of the TCA-cycle intermediates in the soil bacterium Pseudomonas putida KT2440. McpS-LBD was expressed, purified and crystallized in complex with two of its natural ligands (malate and succinate). Crystals were obtained by both the counter-diffusion and the hanging-drop vapour-diffusion techniques after pre-incubation of McpS-LBD with the ligands. The crystals were isomorphous and belonged to space group C2, with two molecules per asymmetric unit. Diffraction data were collected at the ESRF synchrotron X-ray source to resolutions of 1.8 and 1.9 Å for the malate and succinate complexes, respectively

  10. 2-ketogluconic acid secretion by incorporation of Pseudomonas putida KT 2440 gluconate dehydrogenase (gad) operon in Enterobacter asburiae PSI3 improves mineral phosphate solubilization.

    Science.gov (United States)

    Kumar, Chanchal; Yadav, Kavita; Archana, G; Naresh Kumar, G

    2013-09-01

    Enterobacter asburiae PSI3 is known to efficiently solubilize rock phosphate by secretion of approximately 50 mM gluconic acid in Tris-buffered medium in the presence of 75 mM glucose and in a mixture of seven aldosugars each at 15 mM concentration, mimicking alkaline vertisol soils. Efficacy of this bacterium in the rhizosphere requires P release in the presence of low amount of sugars. To achieve this, E. asburiae PSI3 has been manipulated to express gluconate dehydrogenase (gad) operon of Pseudomonas putida KT 2440 to produce 2-ketogluconic acid. E. asburiae PSI3 harboring gad operon had 438 U of GAD activity, secreted 11.63 mM 2-ketogluconic and 21.65 mM gluconic acids in Tris-rock phosphate-buffered medium containing 45 mM glucose. E. asburiae PSI3 gad transformant solubilized 0.84 mM P from rock phosphate in TRP-buffered liquid medium. In the presence of a mixture of seven sugars each at 12 mM, the transformant brought about a drop in pH to 4.1 and released 0.53 mM P. PMID:23666029

  11. Mineralization of Paraoxon and Its Use as a Sole C and P Source by a Rationally Designed Catabolic Pathway in Pseudomonas putida

    OpenAIRE

    de la Peña Mattozzi, Matthew; Tehara, Sundiep K.; Hong, Thomas; Keasling, Jay D.

    2006-01-01

    Organophosphate compounds, which are widely used as pesticides and chemical warfare agents, are cholinesterase inhibitors. These synthetic compounds are resistant to natural degradation and threaten the environment. We constructed a strain of Pseudomonas putida that can efficiently degrade a model organophosphate, paraoxon, and use it as a carbon, energy, and phosphorus source. This strain was engineered with the pnp operon from Pseudomonas sp. strain ENV2030, which encodes enzymes that trans...

  12. Organo-mineral interactions in Pseudomonas putida-birnessite assemblages: Impact on mineral reactivity

    Science.gov (United States)

    Simanova, Anna; Kroll, Alexandra; Pena, Jasquelin

    2016-04-01

    The ability of microorganisms to precipitate biogenic birnessite nanoparticles is widely spread in the bacterial and fungal trees of life, with this process accounting largely for the formation of birnessite in nature. Birnessite minerals occur typically as nanoparticles that exhibit significant chemical and structural disorder. Furthermore, the mineral is embedded within a biomass matrix composed of microbial cells and extracellular polymeric substances, where the biomass not only provides reactive surfaces but can mediate electron transfer reactions. The overarching question guiding our research is: How do nanoscale properties and admixing with microbial biomass modify the reactivity of Mn oxide minerals? In this study, we investigate the biomass-birnessite composites of Pseudomonas putida GB-1 biomass and δ-MnO2 nanoparticles. We characterized the structure and composition of the mineral fraction using X-ray diffraction, Mn K-edge X-ray absorption spectroscopy and wet-chemical methods. To characterize the biomass fraction, we employed FTIR spectroscopy and size-exclusion chromatography analysis of the extracellular polymeric substances. Finally, we measured Ni(II) sorption isotherms at pH 6 and Ni K-edge EXAFS spectra to determine the extent and mechanism of Ni sorption in the biomass-mineral composites and in biomass-only and mineral-only systems. This approach provided direct and indirect evidence for the extent of organo-mineral interactions in the composites, as well as a direct measure of sorption reactivity in the composites relative to biomass-only and mineral-only systems. We found that admixing of mineral nanoparticles with biomass reduced the reactivity of the edge sites of birnessite particles towards Ni(II) through the attachment of organic moieties to the mineral particles and/or modification of the assemblage surface charge properties. In addition, the interaction of biomass components with MnO2 particles leads to partial Mn(IV) reduction and

  13. The regulatory logic of m-xylene biodegradation by Pseudomonas putida mt-2 exposed by dynamic modelling of the principal node Ps/Pr of the TOL plasmid

    NARCIS (Netherlands)

    Koutinas, M.; Lam, M.C.; Kiparissides, A.; Silva-Rocha, R.; Godinho, M.; Livingston, A.G.; Pistikopoulos, E.N.; Lorenzo, de V.; Martins Dos Santos, V.A.P.; Mantalaris, A.

    2010-01-01

    P>The structure of the extant transcriptional control network of the TOL plasmid pWW0 born by Pseudomonas putida mt-2 for biodegradation of m-xylene is far more complex than one would consider necessary from a mere engineering point of view. In order to penetrate the underlying logic of such a ne

  14. Multivariate analysis of microarray data by principal component discriminant analysis: Prioritizing relevant transcripts linked to the degradation of different carbohydrates in Pseudomonas putida S12

    NARCIS (Netherlands)

    Werf, M.J. van der; Pieterse, B.; Luijk, N. van; Schuren, F.; Werff van der - Vat, B. van der; Overkamp, K.; Jellema, R.H.

    2006-01-01

    The value of the multivariate data analysis tools principal component analysis (PCA) and principal component discriminant analysis (PCDA) for prioritizing leads generated by microarrays was evaluated. To this end, Pseudomonas putida S12 was grown in independent triplicate fermentations on four diffe

  15. Metabolic flux analysis of a phenol producing mutant of Pseudomonas putida S12: Verification and complementation of hypotheses derived from transcriptomics

    NARCIS (Netherlands)

    Wierckx, N.; Ruijssenaars, H.J.; Winde, J.H.de; Schmid, A.; Blank, L.M.

    2009-01-01

    The physiological effects of genetic and transcriptional changes observed in a phenol producing mutant of the solvent-tolerant Pseudomonas putida S12 were assessed with metabolic flux analysis. The upregulation of a malate/lactate dehydrogenase encoding gene could be connected to a flux increase fro

  16. Draft Genome Sequence of Pseudomonas putida CBF10-2, a Soil Isolate with Bioremediation Potential in Agricultural and Industrial Environmental Settings.

    Science.gov (United States)

    Iyer, Rupa; Damania, Ashish

    2016-01-01

    Pseudomonas putida CBF10-2 is a microorganism isolated from farmland soil in Fairchild, TX, found to degrade high-impact xenobiotics, including organophosphate insecticides, petroleum hydrocarbons, and both monocyclic and polycyclic aromatics. The versatility of CBF10-2 makes it useful for multipurpose bioremediation of contaminated sites in agricultural and industrial environments. PMID:27417844

  17. Contrasting colonization and plant growth promoting capacity between wild type and gfp-derative of the endophyte Pseudomonas putida W619 in hybrid poplar

    Energy Technology Data Exchange (ETDEWEB)

    Weyens N.; van der Lelie D.; Boulet, J.; Adriaensen, D.; Timmermans, J.-P.; Prinsen, E.; Van Oevelen, S.; D" Haen, J.; Smeets, K.; Taghavi, S.; Vangronsveld, J.

    2011-06-09

    This study aims to investigate the colonization of poplar by the endophyte Pseudomonas putida W619 and its capacity to promote plant growth. Poplar cuttings were inoculated with P. putida W619 (wild-type or gfp-labelled). The colonization of both strains was investigated and morphological, physiological and biochemical parameters were analyzed to evaluate plant growth promotion. Inoculation with P. putida W619 (wild-type) resulted in remarkable growth promotion, decreased activities of antioxidative defence related enzymes, and reduced stomatal resistance, all indicative of improved plant health and growth in comparison with the non-inoculated cuttings. In contrast, inoculation with gfp-labelled P. putida W619 did not promote growth; it even had a negative effect on plant health and growth. Furthermore, compared to the wildtype strain, colonization by the gfp-labelled P. putida W619::gfp1 was much lower; it only colonized the rhizosphere and root cortex while the wild-type strain also colonized the root xylem vessels. Despite the strong plant growth promoting capacity of P. putida W619 (wild-type), after gfp labelling its growth promoting characteristics disappeared and its colonization capacity was strongly influenced; for these reasons gfp labelling should be applied with sufficient caution.

  18. Characterization of a marine-isolated mercury-resistant Pseudomonas putida strain SP1 and its potential application in marine mercury reduction

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Weiwei; Chen, Lingxin; Liu, Dongyan [Chinese Academy of Sciences, Yantai, SD (China). Yantai Inst. of Coastal Zone Research (YICCAS); Chinese Academy of Sciences, Yantai, SD (China). Shandong Provincial Key Lab. of Coastal Zone Environmental Processes

    2012-02-15

    The Pseudomonas putida strain SP1 was isolated from marine environment and was found to be resistant to 280 {mu}M HgCl{sub 2}. SP1 was also highly resistant to other metals, including CdCl{sub 2}, CoCl{sub 2}, CrCl{sub 3}, CuCl{sub 2}, PbCl{sub 2}, and ZnSO{sub 4}, and the antibiotics ampicillin (Ap), kanamycin (Kn), chloramphenicol (Cm), and tetracycline (Tc). mer operon, possessed by most mercury-resistant bacteria, and other diverse types of resistant determinants were all located on the bacterial chromosome. Cold vapor atomic absorption spectrometry and a volatilization test indicated that the isolated P. putida SP1 was able to volatilize almost 100% of the total mercury it was exposed to and could potentially be used for bioremediation in marine environments. The optimal pH for the growth of P. putida SP1 in the presence of HgCl{sub 2} and the removal of HgCl{sub 2} by P. putida SP1 was between 8.0 and 9.0, whereas the optimal pH for the expression of merA, the mercuric reductase enzyme in mer operon that reduces reactive Hg{sup 2+} to volatile and relatively inert monoatomic Hg{sup 0} vapor, was around 5.0. LD50 of P. putida SP1 to flounder and turbot was 1.5 x 10{sup 9} CFU. Biofilm developed by P. putida SP1 was 1- to 3-fold lower than biofilm developed by an aquatic pathogen Pseudomonas fluorescens TSS. The results of this study indicate that P. putida SP1 is a low virulence strain that can potentially be applied in the bioremediation of HgCl{sub 2} contamination over a broad range of pH. (orig.)

  19. Interaction of Cadmium With the Aerobic Bacterium Pseudomonas Mendocina

    Science.gov (United States)

    Schramm, P. J.; Haack, E. A.; Maurice, P. A.

    2006-05-01

    The fate of toxic metals in the environment can be heavily influenced by interaction with bacteria in the vadose zone. This research focuses on the interactions of cadmium with the strict aerobe Pseudomonas mendocina. P. mendocina is a gram-negative bacterium that has shown potential in the bioremediation of recalcitrant organic compounds. Cadmium is a common environmental contaminant of wide-spread ecological consequence. In batch experiments P. mendocina shows typical bacterial growth curves, with an initial lag phase followed by an exponential phase and a stationary to death phase; concomitant with growth was an increase in pH from initial values of 7 to final values at 96 hours of 8.8. Cd both delays the onset of the exponential phase and decreases the maximum population size, as quantified by optical density and microscopic cell counts (DAPI). The total amount of Cd removed from solution increases over time, as does the amount of Cd removed from solution normalized per bacterial cell. Images obtained with transmission electron microscopy (TEM) showed the production of a cadmium, phosphorus, and iron containing precipitate that was similar in form and composition to precipitates formed abiotically at elevated pH. However, by late stationary phase, the precipitate had been re-dissolved, perhaps by biotic processes in order to obtain Fe. Stressed conditions are suggested by TEM images showing the formation of pili, or nanowires, when 20ppm Cd was present and a marked decrease in exopolysaccharide and biofilm material in comparison to control cells (no cadmium added).

  20. Characterization of starvation-induced dispersion in Pseudomonas putida biofilms: genetic elements and molecular mechanisms

    DEFF Research Database (Denmark)

    Gjermansen, M.; Nilsson, M.; Yang, Liang; Tolker-Nielsen, T.

    2010-01-01

    adhesion and were deficient in subsequent biofilm formation, suggesting that LapG affects LapA, and that the LapA protein functions both as a surface adhesin and as a biofilm matrix component. Lowering of the intracellular c-di-GMP level via induction of an EAL domain protein led to dispersal of P. putida...

  1. Toxicities effects of pharmaceutical, olive mill and textile wastewaters before and after degradation by Pseudomonas putida mt-2

    Directory of Open Access Journals (Sweden)

    Mansour Hedi

    2012-02-01

    Full Text Available Abstract Background Removal of numerous classes of chemical pollutants from the industrial wastewater such as textile, pharmaceutical and olive mill using conventional wastewater treatment, is incomplete and several studies suggested that improvement of this situation would require the application of biological treatment techniques. Dyes, polyphenols and drugs are an environmental pollutants extremely toxics to plants and other living organisms including humans. These effluents were previously treated by Pseudomonas putida. The main of this work was to evaluate the in vivo toxicity of the three wastewaters. Methods Writhes and convulsant effect of effluents were carried out and were compared to the treated effluents. Only pharmaceutical wastewater was exhibited a convulsant effect which observed in mice treated by effluent. On the other hand, all industrial wastewater induced significantly an algogenic effects particularly when mice were treated by the pharmaceutical wastewater (Number of writhes = 44. Conclusion Toxicity was totally removed when mice were treated by the bio remediated effluent. This indicates that P. putida was able to completely detoxify the toxic industrial effluent.

  2. Antimicrobial effects of selected plant essential oils on the growth of a Pseudomonas putida strain isolated from meat.

    Science.gov (United States)

    Oussalah, Mounia; Caillet, Stéphane; Saucier, Linda; Lacroix, Monique

    2006-06-01

    The inhibitory effect of 60 different essential oils was evaluated on a Pseudomonas putida strain of meat origin, associated with meat spoilage. Essential oils were tested at concentrations from 0.003 to 0.8% (wt/vol) to determine minimum inhibitory and maximal tolerated concentrations (MIC and MTC, respectively) using an agar medium culture. Of the 60 samples tested, Corydothymus capitatus essential oil was the most active showing a MIC of 0.025% and a MTC of 0.06%. Seven essential oils (Cinnamomum cassia, Origanum compactum, Origanum heracleoticum, Satureja hortensis, Satureja montana, Thymus vulgaris carvacroliferum, Thymus vulgaris thymoliferum) have shown a strong antimicrobial activity against P. putida with a MIC of 0.05% and a MTC ranging from 0.013% to 0.025%. Ten other oils (Cinnamomum verum (leaf and bark), Eugenia caryophyllus, Cymbopogon martinii var. motia, Cymbopogon nardus, Melaleuca linariifolia, Origanum majorana, Pimenta dioica, Thymus satureoides, Thymus serpyllum) showed a high antimicrobial activity showing a MIC ranging from 0.1% to 0.4%, while the remaining were less active showing a MIC⩾0.8%. PMID:22062294

  3. A tricistronic heat shock operon is important for stress tolerance of Pseudomonas putida and conserved in many environmental bacteria.

    Science.gov (United States)

    Krajewski, Stefanie S; Joswig, Matthias; Nagel, Miriam; Narberhaus, Franz

    2014-06-01

    Small heat shock proteins (sHsps) including the well-studied IbpA protein from Escherichia coli are molecular chaperones that bind to non-native proteins and prevent them from aggregation. We discovered an entirely unexplored tricistronic small heat shock gene cluster in Pseudomonas putida. The genes pp3314, pp3313 and pp3312 (renamed to hspX, hspY and hspZ respectively) are transcribed in a single transcript. In addition to σ(32) -dependent transcriptional control, translation of the first and second gene of the operon is controlled by RNA thermometers with novel architectures. Biochemical analysis of HspY, HspZ and P. putida IbpA demonstrated that they assemble into homo-oligomers of different sizes whose quaternary structures alter in a temperature-dependent manner. IbpA and HspY are able to prevent the model substrate citrate synthase from thermal aggregation in vitro. Increased stress sensitivity of a P. putida strain lacking HspX, HspY and HspZ revealed an important role of these sHsps in stress adaptation. The hspXYZ operon is conserved among metabolically related bacteria that live in hostile environments including polluted soils. This heat shock operon might act as a protective system to promote survival in such ecological niches. PMID:24612349

  4. Gene Sequence, Soluble Expression and Homologous Comparison of a D-Hydantoinase from Pseudomonas putida YZ-26

    Institute of Scientific and Technical Information of China (English)

    SHI Ya-wei; ZHAO Li-xia; NIU Li-xi; FENG Xia; YUAN Jing-ming

    2005-01-01

    A 1440bp open-reading frame encoding D-hydantoinase from Pseudomonas putida YZ-26 was cloned and sequenced(GenBank AY387829). The DNA fragment was inserted into Nde and BamHI sites of vector pET-3a, yielding a recombinant plasmid, pET-HDT. After being transferred into the host strain, the artificial strain, pET-HDT/E.coli BL21 can express the D-hydantoinase as the soluble form in the Lura-Bertani medium without addition of any inducers. The activity of the enzyme toward substrate DL-hydantoin can reach 3000-4000 IU per cells from one-liter bacterial culture incubated at 30 ℃ for 10-12 h. By the comparison of amino acid sequence homology, hydrophobic residues analysis and secondary structure prediction, it was found that D-hydantoinase reported herein is quite similar to that from Pseudomonas putdia CCRC12857, and alike to that from Pseudomonas putdia DSM84 or other bacteria. A rapid and efficient purification procedure of the enzyme was performed by a three-step procedure: ammonium sulfate fractionation, phenyl Sepharose hydrophobic interaction chromatography and Sephacryl S-200 gel filtration. The molecular mass of the monomeric enzyme is 52042 Da as determined by MALDI-TOF mass spectrometry.

  5. Nosocomial infections caused by multidrug-resistant isolates of pseudomonas putida producing VIM-1 metallo-beta-lactamase.

    Science.gov (United States)

    Lombardi, Gianluigi; Luzzaro, Francesco; Docquier, Jean-Denis; Riccio, Maria Letizia; Perilli, Mariagrazia; Colì, Alessandra; Amicosante, Gianfranco; Rossolini, Gian Maria; Toniolo, Antonio

    2002-11-01

    Successful carbapenem-based chemotherapy for the treatment of Pseudomonas infections has been seriously hindered by the recent appearance of IMP- and VIM-type metallo-beta-lactamases, which confer high-level resistance to carbapenems and most other beta-lactams. Recently, multidrug-resistant Pseudomonas putida isolates for which carbapenem MICs were >/=32 micro g/ml were recovered from cultures of urine from three inpatients in the general intensive care unit of the Ospedale di Circolo, Varese, Italy. Enzyme assays revealed production of a metallo-beta-lactamase activity, while molecular analysis detected in each isolate a bla(VIM-1) determinant carried by an apparently identical medium-sized plasmid. Conjugation experiments were unsuccessful in transferring the beta-lactamase determinant to Escherichia coli or Pseudomonas aeruginosa. Macrorestriction analysis by pulsed-field gel electrophoresis demonstrated that the isolates were of clonal origin. PCR mapping and sequencing of the variable region of the plasmid-borne class 1 integron carrying the bla(VIM-1) determinant (named In110) showed that the bla(VIM-1)-containing cassette was identical to that previously found in strains of different species from other Italian hospitals and that the cassette array of In110 was not identical but clearly related to that of In70 (a bla(VIM-1)-containing plasmid-borne integron from an Achromobacter xylosoxidans isolate), pointing to a common origin of this cassette and to a related evolutionary history of their cognate integrons. PMID:12409373

  6. Cow Dung Substrate for the Potential Production of Alkaline Proteases by Pseudomonas putida Strain AT in Solid-State Fermentation

    Directory of Open Access Journals (Sweden)

    Ponnuswamy Vijayaraghavan

    2014-01-01

    Full Text Available Cow dung and agroresidues were used as the substrates for the production of alkaline proteases by Pseudomonas putida strain AT in solid-state fermentation. Among the various substrates evaluated, cow dung supported maximum (1351±217 U/g protease production. The optimum conditions for the production of alkaline proteases were a fermentation period of 48 h, 120% (v/w moisture, pH 9, and the addition of 6% (v/w inoculum, 1.5% (w/w trehalose, and 2.0% (w/w yeast extract to the cow dung substrate. The enzyme was active over a range of temperatures (50–70°C and pHs (8–10, with maximum activity at 60°C and pH 9. These enzymes showed stability towards surfactants, detergents, and solvent and digested various natural proteins.

  7. Massilia putida sp. nov., a dimethyl disulfide-producing bacterium isolated from wolfram mine tailing.

    Science.gov (United States)

    Feng, Guang-Da; Yang, Song-Zhen; Li, Hua-Ping; Zhu, Hong-Hui

    2016-01-01

    A heavy metal-resistant and dimethyl disulfide-producing bacterial strain, designated 6NM-7T, was isolated from wolfram mine tailing, Dayu County, Jiangxi Province, PR China. Strain 6NM-7T was aerobic, Gram-stain-negative and motile by means of a single polar flagellum. Phylogenetic analysis, based on 16S rRNA gene sequences, showed that strain 6NM-7T was affiliated with the genus Massilia and was closely related to Massilia norwichensis LMG 28164T (98.8 % 16S rRNA gene sequence similarity), Massilia kyonggiensis KACC 17471T (98.4 %), Massilia niastensis KACC 12599T (97.8 %), Massilia tieshanensis KACC 14940T (97.3 %), Massilia haematophila KACC 13771T (97.2 %), Massilia namucuonensis CGMCC 1.11014T (97.1 %) and Massilia aerilata KACC 12505T (97.1 %). The DNA-DNA relatedness values between strain 6NM-7T and its closely related type strains were all below 70 %. The major respiratory quinone was unbiquinone 8 (Q-8) and the major cellular fatty acids consisted of C16 : 0 (33.2 %), summed feature 3 (C16 : 1ω7c and/or iso-C15 : 0 2-OH; 21.8 %), C17 : 0 cyclo (20.8 %), C18 : 1ω7c (7.4 %) and C10 : 0 3-OH (5.8 %). The major polar lipids consisted of phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol. The genomic DNA G+C content of strain 6NM-7T was 66.8 ± 0.6 mol%. On the basis of the results of this polyphasic taxonomic study, strain 6NM-7T should be assigned to a novel species of the genus Massilia, for which the name Massilia putida sp. nov. is proposed. The type strain is 6NM-7T ( = DSM 27523T = KCTC 42761T). PMID:26449383

  8. ABILITY OF BACTERIAL CONSORTIUM: Bacillus coagulans, Bacilus licheniformis, Bacillus pumilus, Bacillus subtilis, Nitrosomonas sp. and Pseudomonas putida IN BIOREMEDIATION OF WASTE WATER IN CISIRUNG WASTE WATER TREATMENT PLANT

    OpenAIRE

    Ratu SAFITRI; Bambang PRIADIE; Mia MIRANTI; Arum Widi ASTUTI

    2015-01-01

    This study was conducted in order to determine the ability of bacterial consortium: Bacillus coagulans, Bacilus licheniformis, Bacillus pumilus, Bacillus subtilis, Nitrosomonas sp., and Pseudomonas putida in bioremediation of wastewater origin Cisirung WWTP. This study uses an experimental method completely randomized design (CRD), which consists of two treatment factors (8x8 factorial design). The first factor is a consortium of bacteria (K), consisting of 8 level factors (k1, k2, k3, k4, k5...

  9. Alginate Production by Pseudomonas putida Creates a Hydrated Microenvironment and Contributes to Biofilm Architecture and Stress Tolerance under Water-Limiting Conditions▿

    OpenAIRE

    Chang, Woo-Suk; van de Mortel, Martijn; Nielsen, Lindsey; Nino de Guzman, Gabriela; Li, Xiaohong; Halverson, Larry J.

    2007-01-01

    Biofilms exist in a variety of habitats that are routinely or periodically not saturated with water, and residents must integrate cues on water abundance (matric stress) or osmolarity (solute stress) into lifestyle strategies. Here we examine this hypothesis by assessing the extent to which alginate production by Pseudomonas putida strain mt-2 and by other fluorescent pseudomonads occurs in response to water limitations and how the presence of alginate in turn influences biofilm development a...

  10. In-vitro antibacterial activities of the essential oils of aromatic plants against Erwinia herbicola (Lohnis) and pseudomonas putida (Kris Hamilton)

    OpenAIRE

    Pandey Abhay K; Singh Pooja; Palni Uma T.; Tripathi N.N.

    2012-01-01

    This study was designed to examine in vitro antibacterial activities of essential oils extracted from 53 aromatic plants of Gorakhpur Division (UP, INDIA) for the control of two phytopathogenic bacteria namely Erwinia herbicola and Pseudomonas putida causing several post-harvest diseases in fruits and vegetables. Out of 53 oils screened, 8 oils such as Chenopodium ambrosioides, Citrus aurantium, Clausena pentaphylla, Hyptis suaveolens, Lippia alba, Mentha arvensis, Ocimum sanctum and Vi...

  11. Synthesis of Diblock copolymer poly-3-hydroxybutyrate -block-poly-3-hydroxyhexanoate [PHB-b-PHHx] by a β-oxidation weakened Pseudomonas putida KT2442

    OpenAIRE

    Tripathi Lakshmi; Wu Lin-Ping; Chen Jinchun; Chen Guo-Qiang

    2012-01-01

    Abstract Background Block polyhydroxyalkanoates (PHA) were reported to be resistant against polymer aging that negatively affects polymer properties. Recently, more and more attempts have been directed to make PHA block copolymers. Diblock copolymers PHB-b-PHHx consisting of poly-3-hydroxybutyrate (PHB) block covalently bonded with poly-3-hydroxyhexanoate (PHHx) block were for the first time produced successfully by a recombinant Pseudomonas putida KT2442 with its β-oxidation cycle deleted to...

  12. The Homogentisate Pathway: a Central Catabolic Pathway Involved in the Degradation of l-Phenylalanine, l-Tyrosine, and 3-Hydroxyphenylacetate in Pseudomonas putida

    OpenAIRE

    Arias-Barrau, Elsa; Olivera, Elías R.; Luengo, José M.; Fernández, Cristina; Galán, Beatriz; García, José L.; Díaz, Eduardo; Miñambres, Baltasar

    2004-01-01

    Pseudomonas putida metabolizes Phe and Tyr through a peripheral pathway involving hydroxylation of Phe to Tyr (PhhAB), conversion of Tyr into 4-hydroxyphenylpyruvate (TyrB), and formation of homogentisate (Hpd) as the central intermediate. Homogentisate is then catabolized by a central catabolic pathway that involves three enzymes, homogentisate dioxygenase (HmgA), fumarylacetoacetate hydrolase (HmgB), and maleylacetoacetate isomerase (HmgC), finally yielding fumarate and acetoacetate. Wherea...

  13. Reduction of Cell Lysate Viscosity during Processing of Poly(3-Hydroxyalkanoates) by Chromosomal Integration of the Staphylococcal Nuclease Gene in Pseudomonas putida

    OpenAIRE

    Boynton, Zhuang L.; Koon, Joseph J.; Brennan, Elaine M.; Clouart, Jeralyn D.; Horowitz, Daniel M.; Gerngross, Tillman U.; Huisman, Gjalt W.

    1999-01-01

    Poly(3-hydroxyalkanoates) (PHAs) are biodegradable thermoplastics which are accumulated by many bacterial species in the form of intracellular granules and which are thought to serve as reserves of carbon and energy. Pseudomonas putida accumulates a polyester, composed of medium-side-chain 3-hydroxyalkanoic acids, which has excellent film-forming properties. Industrial processing of PHA involves purification of the PHA granules from high-cell-density cultures. After the fermentation process, ...

  14. Effect of pseudobactin 358 production by Pseudomonas putida WCS358 on suppression of fusarium wilt of carnations by nonpathogenic Fusarium oxysporum Fo47.

    OpenAIRE

    Lemanceau, P.; Bakker, P A; de Kogel, W.J.; Alabouvette, C.; Schippers, B.

    1992-01-01

    Nonpathogenic Fusarium oxysporum Fo47b10 combined with Pseudomonas putida WCS358 efficiently suppressed fusarium wilt of carnations grown in soilless culture. This suppression was significantly higher than that obtained by inoculation of either antagonistic microorganism alone. The increased suppression obtained by Fo47b10 combined with WCS358 only occurred when Fo47b10 was introduced at a density high enough (at least 10 times higher than that of the pathogen) to be efficient on its own. P. ...

  15. Cloning and characterization of a bifunctional glycosyl hydrolase from an antagonistic Pseudomonas putida strain P3(4).

    Science.gov (United States)

    Singh, Naosekpam Ajit; Shanmugam, Veerubommu

    2012-06-01

    A fluorescent pseudomonad strain P3(4) showing chitinolysis on chitinase detection agar and antagonism against Fusarium oxysporum f.sp dianthi causing vascular wilt of carnation was isolated from pea rhizosphere soil. PCR primers specific for glycosyl hydrolase family 5 (GH5) of Pseudomonas putida isolate KT2440 amplified a 947 bp fragment of the GH5 gene from P3(4). Cloning of this gene into Escherichia coli M15 using an expression vector pQE-30UA and screening on chitin and chitosan detection agar identified one positive clone (Pchi(+) ). Sequence analysis of the cloned insert revealed an open reading frame of 947 nucleotides corresponding to a protein of 315 amino acids with a predicted molecular mass of 38.0 kDa. The deduced amino acid sequence of the open reading frame (gene product/GH) showed 83-84% homology to the GH5 of P. putida strains F1 and KT2440, respectively. The purified enzyme was homogenous, as examined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and was visualized as single fluorescent band in native gel assay with 4-methylumbelliferyl-N -acetyl-β;-D-glucosaminide and glycol chitosan, respectively. For hydrolysis of 4-nitrophenyl-N -acetyl-β;-D-glucosaminide (pNP-(GlcNAc) and colloidal chitosan, the enzyme had an optimal temperature of 40 °C, and was stable within the temperature range of 10 °C to 40 °C. The enzyme showed an optimal pH of 3.5, with maximum stabilities at 5.0 and 5.5 for hydrolysis of pNP-(GlcNAc) and colloidal chitosan, respectively. Fe(3+) and Cu(2+) stimulated chitinase and chitosanase activities by 74.2 and 51.4%, respectively. The purified GH displayed 70 and 45% inhibition of spore germination of the pathogenic fungi, Fusarium oxysporum f.sp. dianthi and Alternaria solani, respectively. PMID:21953214

  16. Dependence of the initial adhesion of biofilm forming Pseudomonas putida mt2 on physico-chemical material properties.

    Science.gov (United States)

    Montag, Dominik; Frant, Marion; Horn, Harald; Liefeith, Klaus

    2012-01-01

    Bacterial adhesion is strongly dependent on the physico-chemical properties of materials and plays a fundamental role in the development of a growing biofilm. Selected materials were characterized with respect to their physico-chemical surface properties. The different materials, glass and several polymer foils, showed a stepwise range of surface tensions (γ(s)) between 10.3 and 44.7 mN m(-1). Measured zeta potential values were in the range between -74.8 and -28.3 mV. The initial bacterial adhesion parameter q(max) was found to vary between 6.6 × 10(6) and 28.1 × 10(6) cm(-2). By correlation of the initial adhesions kinetic parameters with the surface tension data, the optimal conditions for the immobilization of Pseudomonas putida mt2 were found to be at a surface tension of 24.7 mN m(-1). Both higher and lower surface tensions lead to a smaller number of adherent cells per unit surface area. Higher energy surfaces, commonly termed hydrophilic, could constrain bacterial adhesion because of their more highly ordered water structure (exclusion zone) close to the surface. At low energy surfaces, commonly referred to as hydrophobic, cell adhesion is inhibited due to a thin, less dense zone (depletion layer or clathrate structure) close to the surface. Correlation of q (max) with zeta potential results in a linear relationship. Since P. putida carries weak negative charges, a measurable repulsive effect can be assumed on negative surfaces. PMID:22452391

  17. Functional Characterization of the Mannitol Promoter of Pseudomonas fluorescens DSM 50106 and Its Application for a Mannitol-Inducible Expression System for Pseudomonas putida KT2440.

    Directory of Open Access Journals (Sweden)

    Jana Hoffmann

    Full Text Available A new pBBR1MCS-2-derived vector containing the Pseudomonas fluorescens DSM10506 mannitol promoter PmtlE and mtlR encoding its AraC/XylS type transcriptional activator was constructed and optimized for low basal expression. Mannitol, arabitol, and glucitol-inducible gene expression was demonstrated with Pseudomonas putida and eGFP as reporter gene. The new vector was applied for functional characterization of PmtlE. Identification of the DNA binding site of MtlR was achieved by in vivo eGFP measurement with PmtlE wild type and mutants thereof. Moreover, purified MtlR was applied for detailed in vitro investigations using electrophoretic mobility shift assays and DNaseI footprinting experiments. The obtained data suggest that MtlR binds to PmtlE as a dimer. The proposed DNA binding site of MtlR is AGTGC-N5-AGTAT-N7-AGTGC-N5-AGGAT. The transcription activation mechanism includes two binding sites with different binding affinities, a strong upstream binding site and a weaker downstream binding site. The presence of the weak downstream binding site was shown to be necessary to sustain mannitol-inducibility of PmtlE. Two possible functions of mannitol are discussed; the effector might stabilize binding of the second monomer to the downstream half site or promote transcription activation by inducing a conformational change of the regulator that influences the contact to the RNA polymerase.

  18. Expression of Fap amyloids in Pseudomonas aeruginosa, P. fluorescens, and P. putida results in aggregation and increased biofilm formation

    DEFF Research Database (Denmark)

    Dueholm, Morten S.; Søndergaard, Mads T; Nilsson, Martin;

    2013-01-01

    The fap operon, encoding functional amyloids in Pseudomonas (Fap), is present in most pseudomonads, but so far the expression and importance for biofilm formation has only been investigated for P. fluorescens strain UK4. In this study, we demonstrate the capacity of P. aeruginosa PAO1, P. fluorescens...... Pf-5, and P. putida F1 to express Fap fibrils, and investigated the effect of Fap expression on aggregation and biofilm formation. The fap operon in all three Pseudomonas species conferred the ability to express Fap fibrils as shown using a recombinant approach. This Fap overexpression consistently...

  19. Draft Genome Sequence of Perfluorooctane Acid-Degrading Bacterium Pseudomonas parafulva YAB-1

    OpenAIRE

    Yi, Langbo; Tang, Chongjian; Peng, Qingjing; Peng, Qingzhong; Chai, Liyuan

    2015-01-01

    Pseudomonas parafulva YAB-1, isolated from perfluorinated compound-contaminated soil, has the ability to degrade perfluorooctane acid (PFOA) compound. Here, we report the draft genome sequence and annotation of the PFOA-degrading bacterium P. parafulva YAB-1. The data provide the basis to investigate the molecular mechanism of PFOA metabolism.

  20. Draft Genome Sequence of Perfluorooctane Acid-Degrading Bacterium Pseudomonas parafulva YAB-1

    Science.gov (United States)

    Tang, Chongjian; Peng, Qingjing; Peng, Qingzhong

    2015-01-01

    Pseudomonas parafulva YAB-1, isolated from perfluorinated compound-contaminated soil, has the ability to degrade perfluorooctane acid (PFOA) compound. Here, we report the draft genome sequence and annotation of the PFOA-degrading bacterium P. parafulva YAB-1. The data provide the basis to investigate the molecular mechanism of PFOA metabolism. PMID:26337877

  1. Whole-Genome Shotgun Sequence of Pseudomonas viridiflava, a Bacterium Species Pathogenic to Arabidopsis thaliana

    OpenAIRE

    Lefort, Francois; Calmin, Gautier; Crovadore, Julien; Osteras, Magne; Farinelli, Laurent

    2013-01-01

    We report here the first whole-genome shotgun sequence of Pseudomonas viridiflava strain UASWS38, a bacterium species pathogenic to the biological model plant Arabidopsis thaliana but also usable as a biological control agent and thus of great scientific interest for understanding the genetics of plant-microbe interactions.

  2. Genome sequence of the mycorrhizal helper bacterium Pseudomonas fluorescens BBc6R8

    Energy Technology Data Exchange (ETDEWEB)

    Deveau, Aurelie [French National Insitute for Agricultural Research (INRA); Grob, Harald [University of Bonn, Germany; Morin, Emmanuelle [INRA, Nancy, France; Karpinets, Tatiana V [ORNL; Utturkar, Sagar M [ORNL; Mehnaz, Samina [University of the Punjab, Pakistan; Kurz, Sven [University of Bonn, Germany; Martin, Francis [INRA, Nancy, France; Frey-Klett, Pascale [INRA, Nancy, France; Labbe, Jessy L [ORNL

    2014-01-01

    We report the draft genome sequence of the mycorrhiza helper bacterium Pseudomonas fluorescens strain BBc6R8 . Several traits which could be involved in the mycorrhiza helper ability of the bacterial strain such as multiple secretion systems, auxin metabolism and phosphate mobilization were evidenced in the genome.

  3. Potential of the TCE-degrading endophyte Pseudomonas putida W619-TCE to improve plant growth and reduce TCE phytotoxicity and evapotranspiration in poplar cuttings

    Energy Technology Data Exchange (ETDEWEB)

    Weyens, N.; van der Lelie, D.; Truyens, S.; Dupae, J.; Newman, L.; Taghavi, S.; Carleer, R.; Vangronsveld, J.

    2010-09-01

    The TCE-degrading poplar endophyte Pseudomonas putida W619-TCE was inoculated in poplar cuttings, exposed to 0, 200 and 400 mg l{sup -1} TCE, that were grown in two different experimental setups. During a short-term experiment, plants were grown hydroponically in half strength Hoagland nutrient solution and exposed to TCE for 3 days. Inoculation with P. putida W619-TCE promoted plant growth, reduced TCE phytotoxicity and reduced the amount of TCE present in the leaves. During a mid-term experiment, plants were grown in potting soil and exposed to TCE for 3 weeks. Here, inoculation with P. putida W619-TCE had a less pronounced positive effect on plant growth and TCE phytotoxicity, but resulted in strongly reduced amounts of TCE in leaves and roots of plants exposed to 400 mg l{sup -1} TCE, accompanied by a lowered evapotranspiration of TCE. Dichloroacetic acid (DCAA) and trichloroacetic acid (TCAA), which are known intermediates of TCE degradation, were not detected. The endophyte P. putida W619-TCE degrades TCE during its transport through the xylem, leading to reduced TCE concentrations in poplar, and decreased TCE evapotranspiration.

  4. Potential of the TCE-degrading endophyte Pseudomonas putida W619-TCE to improve plant growth and reduce TCE phytotoxicity and evapotranspiration in poplar cuttings

    International Nuclear Information System (INIS)

    The TCE-degrading poplar endophyte Pseudomonas putida W619-TCE was inoculated in poplar cuttings, exposed to 0, 200 and 400 mg l-1 TCE, that were grown in two different experimental setups. During a short-term experiment, plants were grown hydroponically in half strength Hoagland nutrient solution and exposed to TCE for 3 days. Inoculation with P. putida W619-TCE promoted plant growth, reduced TCE phytotoxicity and reduced the amount of TCE present in the leaves. During a mid-term experiment, plants were grown in potting soil and exposed to TCE for 3 weeks. Here, inoculation with P. putida W619-TCE had a less pronounced positive effect on plant growth and TCE phytotoxicity, but resulted in strongly reduced amounts of TCE in leaves and roots of plants exposed to 400 mg l-1 TCE, accompanied by a lowered evapotranspiration of TCE. Dichloroacetic acid (DCAA) and trichloroacetic acid (TCAA), which are known intermediates of TCE degradation, were not detected. - The endophyte P. putida W619-TCE degrades TCE during its transport through the xylem, leading to reduced TCE concentrations in poplar, and decreased TCE evapotranspiration.

  5. U(VI) biosorption by bi-functionalized Pseudomonas putida @ chitosan bead: Modeling and optimization using RSM.

    Science.gov (United States)

    Sohbatzadeh, Hozhabr; Keshtkar, Ali Reza; Safdari, Jaber; Fatemi, Faezeh

    2016-08-01

    In this work, Pseudomonas putida cells immobilized into chitosan beads (PICB) were synthesized to investigate the impact of microorganism entrapment on biosorption capacity of prepared biosorbent for U(VI) biosorption from aqueous solutions. Response Surface Methodology (RSM) based on Central Composite Design (CCD) was utilized to evaluate the performance of the PICB in comparison with chitosan beads (CB) under batch mode. Performing experiments under optimal condition sets viz. pH 5, initial U(VI) concentration 500mg/L, biosorbent dosage 0.4g/L and 20wt.% bacterial cells showed that the observed biosorption capacity enhanced by 1.27 times from 398mg/g (CB) to 504mg/g (PICB) that confirmed the effectiveness of cells immobilization process. FTIR and potentiometric titration were then utilized to characterize the prepared biosorbents. While the dominant functional group in the binding process was NH3(+) (4.78meq/g) in the CB, the functional groups of NH3(+), NH2, OH, COOH (6.00meq/g) were responsible for the PICB. The equilibrium and kinetic studies revealed that the Langmuir isotherm model and the pseudo-second-order kinetic model were in better fitness with the CB and PICB experimental data. In conclusion, the present study indicated that the PICB could be a suitable biosorbent for uranium (VI) biosorption from aqueous solutions. PMID:27180295

  6. Growth stimulation of Bacillus cereus and Pseudomonas putida using nanostructured ZnO thin film as transducer element

    Energy Technology Data Exchange (ETDEWEB)

    Loukanov, Alexandre, E-mail: loukanov@mail.saitama-u.ac.jp [Saitama University, Department of Chemistry, Faculty of Science (Japan); Filipov, Chavdar [University of Forestry, Department of Infectious pathology, hygiene, technology and control of food stuffs of animal origin, Faculty of Veterinary Medicine (Bulgaria); Valcheva, Violeta [Bulgarian Academy of Science, Department of Infectious Diseases, Institute of microbiology (Bulgaria); Lecheva, Marta [University of Mining and Geology “St. Ivan Rilski”, Laboratory of Engineering NanoBiotechnology, Department of Engineering Geoecology (Bulgaria); Emin, Saim [University of Nova Gorica, Materials Research Laboratory (Slovenia)

    2015-04-15

    The semiconductor zinc oxide nanomaterial (ZnO or ZnO:H) is widely used in advanced biosensor technology for the design of highly-sensitive detector elements for various applications. In the attempt to evaluate its effect on common microorganisms, two types of nanostructured transducer films have been used (average diameter 600–1000 nm). They have been prepared by using both wet sol–gel method and magnetron sputtering. Their polycrystalline structure and specific surface features have been analyzed by X-ray diffraction (XRD), scanning electron microscope, and atomic force microscope. The assessment of growth stimulation of bacteria was determined using epifluorescent microscope by cell staining with Live/Dead BacLight kit. In our experiments, the growth stimulation of Gram-positive and Gram-negative bacteria on nanostructured ZnO film is demonstrated by Bacillus cereus and Pseudomonas putida. These two bacterial species have been selected, because they are well known and studied in biosensor technologies, with structural difference of their cell walls. These pathogens are easy for with common source in the liquid food or some commercial products. Our data has revealed that the method of transducer film preparation influences strongly bacterial inhibition and division. These results present the transforming signal precisely, when ZnO is used in biosensor applications.

  7. Integration of chemotaxis, transport and catabolism in Pseudomonas putida and identification of the aromatic acid chemoreceptor PcaY.

    Science.gov (United States)

    Luu, Rita A; Kootstra, Joshua D; Nesteryuk, Vasyl; Brunton, Ceanne N; Parales, Juanito V; Ditty, Jayna L; Parales, Rebecca E

    2015-04-01

    Aromatic and hydroaromatic compounds that are metabolized through the β-ketoadipate catabolic pathway serve as chemoattractants for Pseudomonas putida F1. A screen of P. putida F1 mutants, each lacking one of the genes encoding the 18 putative methyl-accepting chemotaxis proteins (MCPs), revealed that pcaY encodes the MCP required for metabolism-independent chemotaxis to vanillate, vanillin, 4-hydroxybenzoate, benzoate, protocatechuate, quinate, shikimate, as well as 10 substituted benzoates that do not serve as growth substrates for P. putida F1. Chemotaxis was induced during growth on aromatic compounds, and an analysis of a pcaY-lacZ fusion revealed that pcaY is expressed in the presence of β-ketoadipate, a common intermediate in the pathway. pcaY expression also required the transcriptional activator PcaR, indicating that pcaY is a member of the pca regulon, which includes three unlinked gene clusters that encode five enzymes required for the conversion of 4-hydroxybenzoate to tricarboxylic acid cycle intermediates as well as the major facilitator superfamily transport protein PcaK. The 4-hydroxybenzoate permease PcaK was shown to modulate the chemotactic response by facilitating the uptake of 4-hydroxybenzoate, which leads to the accumulation of β-ketoadipate, thereby increasing pcaY expression. The results show that chemotaxis, transport and metabolism of aromatic compounds are intimately linked in P. putida. PMID:25582673

  8. Production and characterization of a bacteriocin-like inhibitory substance produced by indigenous soil associated pseudomonas putida mas-1

    International Nuclear Information System (INIS)

    Bacteriocins have been the subject of extensive research globally due to wide range applications. The aim of this research was to investigate the production of bacteriocin(s) or bacteriocin like inhibitory substance(s) by Pseudomonas putida MAS-1 strain. The bacteriocin produced (Putidacin MAS-1) was found bioactive against clinical Staphylococcus aureus and Enterococcus faecalis strains. Bioactivity was observed by stab and overlay assay and multiwell antagonistic activity assay. Putidacin MAS-1 was sensitive beyond 70 degree C but stable at wide pH range (3 to 8). Bioactivity of putidacin MAS-1 was lost after treatment with trypsin and protease while partially lost after Proteinase K treatment. Treatment with ethanol, methanol, chloroform, acetone Tween 20 and Tween 80 showed partial decrease in bioactivity. SDS had stimulatory effect on putidacin MAS-1 bioactivity. EDTA however, showed no effect on the bacteriocin bioactivity. It was partially purified by ammonium sulphate precipitation. SDS-PAGE showed that Putidacin MAS-1 had 15 kDa molecular weight. (author)

  9. Stability of a Pseudomonas putida KT2440 bacteriophage-carried genomic island and its impact on rhizosphere fitness.

    Science.gov (United States)

    Quesada, Jose M; Soriano, María Isabel; Espinosa-Urgel, Manuel

    2012-10-01

    The stability of seven genomic islands of Pseudomonas putida KT2440 with predicted potential for mobilization was studied in bacterial populations associated with the rhizosphere of corn plants by multiplex PCR. DNA rearrangements were detected for only one of them (GI28), which was lost at high frequency. This genomic island of 39.4 kb, with 53 open reading frames, shows the characteristic organization of genes belonging to tailed phages. We present evidence indicating that it corresponds to the lysogenic state of a functional bacteriophage that we have designated Pspu28. Integrated and rarely excised forms of Pspu28 coexist in KT2440 populations. Pspu28 is self-transmissible, and an excisionase is essential for its removal from the bacterial chromosome. The excised Pspu28 forms a circular element that can integrate into the chromosome at a specific location, att sites containing a 17-bp direct repeat sequence. Excision/insertion of Pspu28 alters the promoter sequence and changes the expression level of PP_1531, which encodes a predicted arsenate reductase. Finally, we show that the presence of Pspu28 in the lysogenic state has a negative effect on bacterial fitness in the rhizosphere under conditions of intraspecific competition, thus explaining why clones having lost this mobile element are recovered from that environment. PMID:22843519

  10. Growth stimulation of Bacillus cereus and Pseudomonas putida using nanostructured ZnO thin film as transducer element

    International Nuclear Information System (INIS)

    The semiconductor zinc oxide nanomaterial (ZnO or ZnO:H) is widely used in advanced biosensor technology for the design of highly-sensitive detector elements for various applications. In the attempt to evaluate its effect on common microorganisms, two types of nanostructured transducer films have been used (average diameter 600–1000 nm). They have been prepared by using both wet sol–gel method and magnetron sputtering. Their polycrystalline structure and specific surface features have been analyzed by X-ray diffraction (XRD), scanning electron microscope, and atomic force microscope. The assessment of growth stimulation of bacteria was determined using epifluorescent microscope by cell staining with Live/Dead BacLight kit. In our experiments, the growth stimulation of Gram-positive and Gram-negative bacteria on nanostructured ZnO film is demonstrated by Bacillus cereus and Pseudomonas putida. These two bacterial species have been selected, because they are well known and studied in biosensor technologies, with structural difference of their cell walls. These pathogens are easy for with common source in the liquid food or some commercial products. Our data has revealed that the method of transducer film preparation influences strongly bacterial inhibition and division. These results present the transforming signal precisely, when ZnO is used in biosensor applications

  11. P-cresol and 3,5-xylenol methylhydroxylases in Pseudomonas putida N.C.I.B. 9896.

    Science.gov (United States)

    Keat, M J; Hopper, D J

    1978-01-01

    Pseudomonas putida N.C.I.B. 9869, when grown on 3,5-xylenol, hydroxylates the methyl groups on 3,5-xylenol and on p-cresol by two different enzymes. 3,5-Xylenol methylhydroxylase, studied only in relatively crude extracts, requires NADH, is not active with p-cresol and is inhibited by cyanide, but not by CO. The p-cresol methylhydroxylase requires an electron acceptor and will act under anaerobic conditions. It was purified and is a flavocytochrome c of mol.wt. approx. 114,000 consisting of two subunits of equal size. The enzyme catalyses the hydroxylation of p-cresol (Km 16 micron) and the further oxidation of product, p-hydroxybenzyl alcohol (Km 27 micron) to p-hydroxybenzaldehyde. A different p-cresol methylhydroxylase of the flavocytochrome c type is induced by growth on p-cresol. It too was purified and has mol.wt. approx. 100,000, and again consisted of two equal-size subunits. The Km for p=cresol 3.6 micron and for p=hydroxybenzyl alcohol, 15 micron. PMID:743215

  12. Metabolic Engineering of Pseudomonas putida KT2440 for Complete Mineralization of Methyl Parathion and γ-Hexachlorocyclohexane.

    Science.gov (United States)

    Gong, Ting; Liu, Ruihua; Zuo, Zhenqiang; Che, You; Yu, Huilei; Song, Cunjiang; Yang, Chao

    2016-05-20

    Agricultural soils are often cocontaminated with multiple pesticides. Unfortunately, microorganisms isolated from natural environments do not possess the ability to simultaneously degrade different classes of pesticides. Currently, we can use the approaches of synthetic biology to create a strain endowed with various catabolic pathways that do not exist in a natural microorganism. Here, we describe the metabolic engineering of a biosafety Pseudomonas putida strain KT2440 for complete mineralization of methyl parathion (MP) and γ-hexachlorocyclohexane (γ-HCH) by functional assembly of the MP and γ-HCH mineralization pathways. The engineered strain was genetically stable, and no growth inhibition was observed. Such a strain not only would reduce the toxicity of MP and γ-HCH but also would prevent the accumulation of potentially toxic intermediates in the environment. Furthermore, expression of Vitreoscilla hemoglobin improved the ability of the engineered strain to sequester O2. The inoculation of the engineered strain to soils treated with MP and γ-HCH resulted in a higher degradation rate than in noninoculated soils. Moreover, introduced GFP may be used to monitor the activity of the engineered strain during bioremediation. The engineered strain may be a promising candidate for in situ bioremediation of soil cocontaminated with MP and γ-HCH. PMID:26854500

  13. In vivo gene expression of Pseudomonas putida KT2440 in the rhizosphere of different plants

    OpenAIRE

    Fernández, Matilde; Conde, Susana; Duque, Estrella; Ramos, Juan-Luis

    2013-01-01

    Pseudomonas putida KT2440 has the ability to colonize the rhizosphere of a wide range of plants and can reach cell densities in the range of 105–106 cfu g soil−1. Using the IVET technology we investigated which KT2440 genes were expressed in the rhizosphere of four different plants: pine, cypress, evergreen oak and rosemary. We identified 39 different transcriptional fusions containing the promoters of annotated genes that were preferentially expressed in the rhizosphere. Six of them were exp...

  14. The impact of ColRS two-component system and TtgABC efflux pump on phenol tolerance of Pseudomonas putida becomes evident only in growing bacteria

    Directory of Open Access Journals (Sweden)

    Kivisaar Maia

    2010-04-01

    Full Text Available Abstract Background We have recently found that Pseudomonas putida deficient in ColRS two-component system is sensitive to phenol and displays a serious defect on solid glucose medium where subpopulation of bacteria lyses. The latter phenotype is significantly enhanced by the presence of phenol in growth medium. Here, we focused on identification of factors affecting phenol tolerance of the colR-deficient P. putida. Results By using transposon mutagenesis approach we identified a set of phenol-tolerant derivatives of colR-deficient strain. Surprisingly, half of independent phenol tolerant clones possessed miniTn5 insertion in the ttgABC operon. However, though inactivation of TtgABC efflux pump significantly enhanced phenol tolerance, it did not affect phenol-enhanced autolysis of the colR mutant on glucose medium indicating that phenol- and glucose-caused stresses experienced by the colR-deficient P. putida are not coupled. Inactivation of TtgABC pump significantly increased the phenol tolerance of the wild-type P. putida as well. Comparison of phenol tolerance of growing versus starving bacteria revealed that both ColRS and TtgABC systems affect phenol tolerance only under growth conditions and not under starvation. Flow cytometry analysis showed that phenol strongly inhibited cell division and to some extent also caused cell membrane permeabilization to propidium iodide. Single cell analysis of populations of the ttgC- and colRttgC-deficient strains revealed that their membrane permeabilization by phenol resembles that of the wild-type and the colR mutant, respectively. However, cell division of P. putida with inactivated TtgABC pump seemed to be less sensitive to phenol than that of the parental strain. At the same time, cell division appeared to be more inhibited in the colR-mutant strain than in the wild-type P. putida. Conclusions ColRS signal system and TtgABC efflux pump are involved in the phenol tolerance of P. putida. However, as

  15. The Complete Genome Sequence of the Plant Growth-Promoting Bacterium Pseudomonas sp. UW4

    OpenAIRE

    Duan, Jin; Jiang, Wei; Cheng, Zhenyu; Heikkila, John J.; Bernard R. Glick

    2013-01-01

    The plant growth-promoting bacterium (PGPB) Pseudomonas sp. UW4, previously isolated from the rhizosphere of common reeds growing on the campus of the University of Waterloo, promotes plant growth in the presence of different environmental stresses, such as flooding, high concentrations of salt, cold, heavy metals, drought and phytopathogens. In this work, the genome sequence of UW4 was obtained by pyrosequencing and the gaps between the contigs were closed by directed PCR. The P. sp. UW4 gen...

  16. ISOLATION AND IDENTIFICATION OF A THERMOTOLERANT PLANT GROWTH PROMOTING PSEUDOMONAS PUTIDA PRODUCING TREHALOSE SYNTHASE

    OpenAIRE

    Ali Sk.Z.; Sandhya Vardharajula

    2013-01-01

    A thermotolerant plant growth promoting Pseudomonas isolate growing at 40oC producing trehalose synthase (TreS) was isolated from rhizosphere soil under semi arid conditions of India. Trehalose synthase was extracted; purified and enzymatic activity was examined at various temperatures and pH. The optimum temperature and pH was 38oC and pH 7.5 and the activity declined at above or below the optimum pH and temperature. The enzyme was active on maltose and trehalose among saccharides tested. Th...

  17. Pseudomonas putida attunes morphophysiological, biochemical and molecular responses in Cicer arietinum L. during drought stress and recovery.

    Science.gov (United States)

    Tiwari, Shalini; Lata, Charu; Chauhan, Puneet Singh; Nautiyal, Chandra Shekhar

    2016-02-01

    Drought is one of the most important abiotic stresses that adversely affect plant growth and yield potential. However, some drought resistant rhizosphere competent bacteria are known to improve plant health and promote growth during abiotic stresses. Present study showed the role of Pseudomonas putida MTCC5279 (RA) in ameliorating drought stress on cv. BG-362 (desi) and cv. BG-1003 (kabuli) chickpea cultivars under in vitro and green house conditions. Polyethylene glycol-induced drought stress severely affected seed germination in both cultivars which was considerably improved on RA-inoculation. Drought stress significantly affected various growth parameters, water status, membrane integrity, osmolyte accumulation, ROS scavenging ability and stress-responsive gene expressions, which were positively modulated upon application of RA in both chickpea cultivars. Quantitative real-time (qRT)-PCR analysis showed differential expression of genes involved in transcription activation (DREB1A and NAC1), stress response (LEA and DHN), ROS scavenging (CAT, APX, GST), ethylene biosynthesis (ACO and ACS), salicylic acid (PR1) and jasmonate (MYC2) signalling in both chickpea cultivars exposed to drought stress and recovery in the presence or absence of RA. The observations imply that RA confers drought tolerance in chickpea by altering various physical, physiological and biochemical parameters, as well as by modulating differential expression of at least 11 stress-responsive genes. To the best of our knowledge, this is the first report on detailed analysis of plant growth promotion and stress alleviation in one month old desi and kabuli chickpea subjected to drought stress for 0, 1, 3 and 7 days and recovery in the presence of a PGPR. PMID:26744996

  18. Energetics and Surface Properties of Pseudomonas putida DOT-T1E in a Two-Phase Fermentation System with 1-Decanol as Second Phase

    OpenAIRE

    Neumann, G.; Cornelissen, S.; Breukelen, van, R.; Hunger, S; Lippold, H.; Loffhagen, N.; Wick, L.Y.; Heipieper, H.J.

    2006-01-01

    The solvent-tolerant strain Pseudomonas putida DOT-TIE was grown in batch fermentations in a 5-liter bioreactor in the presence and absence of 10% (vol/vol) of the organic solvent 1-decanol. The growth behavior and cellular energetics, such as the cellular ATP content and the energy charge, as well as the cell surface hydrophobicity and charge, were measured in cells growing in the presence and absence of 1-decanol. Although the cells growing in the presence of 1-decanol showed an about 10% r...

  19. Prediction of the Adaptability of Pseudomonas putida DOT-T1E to a Second Phase of a Solvent for Economically Sound Two-Phase Biotransformations

    OpenAIRE

    Neumann, Grit; Kabelitz, Nadja; Zehnsdorf, Andreas; Miltner, Anja; Lippold, Holger; Meyer, Daniel; Schmid, Andreas; Heipieper, Hermann J

    2005-01-01

    The strain Pseudomonas putida DOT-T1E was tested for its ability to tolerate second phases of different alkanols for their use as solvents in two-liquid-phase biotransformations. Although 1-decanol showed an about 10-fold higher toxicity to the cells than 1-octanol, the cells were able to adapt completely to 1-decanol only and could not be adapted in order to grow stably in the presence of a second phase of 1-octanol. The main explanation for this observation can be seen in the higher water a...

  20. In Vitro Transcriptional Studies of the bkd Operon of Pseudomonas putida: l-Branched-Chain Amino Acids and d-Leucine Are the Inducers

    OpenAIRE

    Madhusudhan, Kunapuli T.; Luo, Jinhe; Sokatch, John R.

    1999-01-01

    BkdR is the transcriptional activator of the bkd operon, which encodes the four proteins of the branched-chain keto acid dehydrogenase multienzyme complex of Pseudomonas putida. In this study, hydroxyl radical footprinting revealed that BkdR bound to only one face of DNA over the same region identified in DNase I protection assays. Deletions of even a few bases in the 5′ region of the BkdR-binding site greatly reduced transcription, confirming that the entire protected region is necessary for...

  1. Microbial Antagonism at the Root Level Is Involved in the Suppression of Fusarium Wilt by the Combination of Nonpathogenic Fusarium oxysporum Fo47 and Pseudomonas putida WCS358

    OpenAIRE

    Duijff, B.J. (Ben); Recorbet, Ghislaine; Bakker, P. A. H. M.; Loper, J E; Lemanceau, Philippe

    2001-01-01

    Two biological control agents, nonpathogenic Fusarium oxysporum Fo47 and Pseudomonas putida WCS358, were evaluated for suppression of Fusarium wilt of flax grown in nutrient solution and for suppression of the population density and metabolic activity of the causal organism F. oxysporum f. sp. lini strain Foln3GUS on root surfaces. Due to the presence of an introduced gusA reporter gene construct in Foln3GUS, the pathogen expressed b-glucuronidase activity that was related to its carbon metab...

  2. Pseudomonas putida のL-メチオニン分解系オペロンの解析

    OpenAIRE

    井上, 浩之; 田村, 隆; 稲垣, 賢二; 田中, 英彦

    1998-01-01

    The mde operon and an upstream regulatory gene (mdeR) have been cloned and sequenced from Pseudomonas putida chromosomal DNA. The mde operon contains two structural genes involved in L-methionine degradative metabolism, which are mdeA (L-methionine γ-lyase gene) and mdeB (a gene encoding a homologous protein to the E1 component of pyruvate dehydrogenase complex). A rho-independent terminator was present just downstream of mdeB and open reading frames corresponding to other components of α-ket...

  3. Genome Sequence of Pseudomonas sp. Strain S9, an Extracellular Arylsulfatase-Producing Bacterium Isolated from Mangrove Soil ▿

    OpenAIRE

    Long, Mengxian; Ruan, Lingwei; Yu, Ziniu; Xu, Xun

    2011-01-01

    Pseudomonas sp. strain S9 was originally isolated from mangrove soil in Xiamen, China. It is an aerobic bacterium which shows extracellular arylsulfatase activity. Here, we describe the 4.8-Mb draft genome sequence of Pseudomonas sp. S9, which exhibits novel cysteine-type sulfatases.

  4. Expression, purification and preliminary crystallographic studies of NahF, a salicylaldehyde dehydrogenase from Pseudomonas putida G7 involved in naphthalene degradation

    International Nuclear Information System (INIS)

    NahF is a salicylaldehyde dehydrogenase that is involved in the naphthalene-degradation pathway, converting salicylaldehyde into salicylate. The subcloning, expression, purification and preliminary X-ray diffraction studies at 2.42 Å resolution of P. putida G7 NahF are reported. Pseudomonas putida G7 is one of the most studied naphthalene-degrading species. The nah operon in P. putida, which is present on the 83 kb metabolic plasmid NAH7, codes for enzymes involved in the conversion of naphthalene to salicylate. The enzyme NahF (salicylaldehyde dehydrogenase) catalyzes the last reaction in this pathway. The nahF gene was subcloned into the pET28a(TEV) vector and the recombinant protein was overexpressed in Escherichia coli Arctic Express at 285 K. The soluble protein was purified by affinity chromatography followed by gel filtration. Crystals of recombinant NahF (6×His-NahF) were obtained at 291 K and diffracted to 2.42 Å resolution. They belonged to the hexagonal space group P6422, with unit-cell parameters a = b = 169.47, c = 157.94 Å. The asymmetric unit contained a monomer and a crystallographic twofold axis generated the dimeric biological unit

  5. A newly isolated Pseudomonas putida S-1 strain for batch-mode-propanethiol degradation and continuous treatment of propanethiol-containing waste gas.

    Science.gov (United States)

    Chen, Dong-Zhi; Sun, Yi-Ming; Han, Li-Mei; Chen, Jing; Ye, Jie-Xu; Chen, Jian-Meng

    2016-01-25

    Pseudomonas putida S-1 was isolated from activated sludge. This novel strain was capable of degrading malodorous 1-propanethiol (PT). PT degradation commenced with no lag phase by cells pre-grown in nutrition-rich media, such as Luria-Bertani (LB), and PT-contained mineral medium at specific growth rates of 0.10-0.19 h(-1); this phenomenon indicated the operability of a large-scale cell culture. A possible PT degradation pathway was proposed on the basis of the detected metabolites, including dipropyl disulfide, 3-hexanone, 2-hexanone, 3-hexanol, 2-hexanol, S(0), SO4(2-), and CO2. P. putida S-1 could degrade mixed pollutants containing PT, diethyl disulfide, isopropyl alcohol, and acetaldehyde, and LB-pre-cultured cells underwent diauxic growth. Waste gas contaminated with 200-400 mg/m(3) PT was continuously treated by P. putida S-1 pre-cultured in LB medium in a completely stirred tank reactor. The removal efficiencies exceeded 88% when PT stream was mixed with 200 mg/m(3) isopropanol; by contrast, the removal efficiencies decreased to 60% as the empty bed residence time was shortened from 40 s to 20 s. PMID:26476310

  6. Quantitative 'Omics Analyses of Medium Chain Length Polyhydroxyalkanaote Metabolism in Pseudomonas putida LS46 Cultured with Waste Glycerol and Waste Fatty Acids.

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    Jilagamazhi Fu

    Full Text Available Transcriptomes and proteomes of Pseudomonas putida LS46 cultured with biodiesel-derived waste glycerol or waste free fatty acids, as sole carbon sources, were compared under conditions that were either permissive or non-permissive for synthesis of medium chain length polyhydroxyalkanoates (mcl-PHA. The objectives of this study were to elucidate mechanisms that influence activation of biopolymer synthesis, intra-cellular accumulation, and monomer composition, and determine if these were physiologically specific to the carbon sources used for growth of P. putida LS46. Active mcl-PHA synthesis by P. putida LS46 was associated with high expression levels of key mcl-PHA biosynthesis genes and/or gene products including monomer-supplying proteins, PHA synthases, and granule-associated proteins. 'Omics data suggested that expression of these genes were regulated by different genetic mechanisms in P. putida LS46 cells in different physiological states, when cultured on the two waste carbon sources. Optimal polymer production by P. putida LS46 was primarily limited by less efficient glycerol metabolism during mcl-PHA synthesis on waste glycerol. Mapping the 'Omics data to the mcl-PHA biosynthetic pathway revealed significant variations in gene expression, primarily involved in: 1 glycerol transportation; 2 enzymatic reactions that recycle reducing equivalents and produce key mcl-PHA biosynthesis pathway intermediates (e.g. NADH/NADPH, acetyl-CoA. Active synthesis of mcl-PHAs was observed during exponential phase in cultures with waste free fatty acids, and was associated with the fatty acid beta-oxidation pathway. A putative Thioesterase in the beta-oxidation pathway that may regulate the level of fatty acid beta-oxidation intermediates, and thus carbon flux to mcl-PHA biosynthesis, was highly up-regulated. Finally, the data suggested that differences in expression of selected fatty acid metabolism and mcl-PHA monomer-supplying enzymes may play a role in

  7. A reduction in growth rate of Pseudomonas putida KT2442 counteracts productivity advances in medium-chain-length polyhydroxyalkanoate production from gluconate

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    Zinn Manfred

    2011-04-01

    Full Text Available Abstract Background The substitution of plastics based on fossil raw material by biodegradable plastics produced from renewable resources is of crucial importance in a context of oil scarcity and overflowing plastic landfills. One of the most promising organisms for the manufacturing of medium-chain-length polyhydroxyalkanoates (mcl-PHA is Pseudomonas putida KT2440 which can accumulate large amounts of polymer from cheap substrates such as glucose. Current research focuses on enhancing the strain production capacity and synthesizing polymers with novel material properties. Many of the corresponding protocols for strain engineering rely on the rifampicin-resistant variant, P. putida KT2442. However, it remains unclear whether these two strains can be treated as equivalent in terms of mcl-PHA production, as the underlying antibiotic resistance mechanism involves a modification in the RNA polymerase and thus has ample potential for interfering with global transcription. Results To assess PHA production in P. putida KT2440 and KT2442, we characterized the growth and PHA accumulation on three categories of substrate: PHA-related (octanoate, PHA-unrelated (gluconate and poor PHA substrate (citrate. The strains showed clear differences of growth rate on gluconate and citrate (reduction for KT2442 > 3-fold and > 1.5-fold, respectively but not on octanoate. In addition, P. putida KT2442 PHA-free biomass significantly decreased after nitrogen depletion on gluconate. In an attempt to narrow down the range of possible reasons for this different behavior, the uptake of gluconate and extracellular release of the oxidized product 2-ketogluconate were measured. The results suggested that the reason has to be an inefficient transport or metabolization of 2-ketogluconate while an alteration of gluconate uptake and conversion to 2-ketogluconate could be excluded. Conclusions The study illustrates that the recruitment of a pleiotropic mutation, whose effects might

  8. ABILITY OF BACTERIAL CONSORTIUM: Bacillus coagulans, Bacilus licheniformis, Bacillus pumilus, Bacillus subtilis, Nitrosomonas sp. and Pseudomonas putida IN BIOREMEDIATION OF WASTE WATER IN CISIRUNG WASTE WATER TREATMENT PLANT

    Directory of Open Access Journals (Sweden)

    Ratu SAFITRI

    2015-10-01

    Full Text Available This study was conducted in order to determine the ability of bacterial consortium: Bacillus coagulans, Bacilus licheniformis, Bacillus pumilus, Bacillus subtilis, Nitrosomonas sp., and Pseudomonas putida in bioremediation of wastewater origin Cisirung WWTP. This study uses an experimental method completely randomized design (CRD, which consists of two treatment factors (8x8 factorial design. The first factor is a consortium of bacteria (K, consisting of 8 level factors (k1, k2, k3, k4, k5, k6, k7, and k8. The second factor is the time (T, consisting of a 7 level factors (t0, t1, t2, t3, t4, t5, t6, and t7. Test parameters consist of BOD (Biochemical Oxygen Demand, COD (Chemical Oxygen Demand, TSS (Total Suspended Solid, Ammonia and Population of Microbes during bioremediation. Data were analyzed by ANOVA, followed by Duncan test. The results of this study showed that the consortium of Bacillus pumilus, Bacillus subtilis, Bacillus coagulans, Nitrosomonas sp., and Pseudomonas putida with inoculum concentration of 5% (k6 is a consortium of the most effective in reducing BOD 71.93%, 64.30% COD, TSS 94.85%, and 88.58% of ammonia.

  9. Mutagenesis and reparation processes in the methylotrophic bacterium Pseudomonas methanolica after UV irradiation

    International Nuclear Information System (INIS)

    High resistance of cells of methylotrophic bacterium Pseudomonas methanolica to bactericidal and mutagenous effects of ultraviolet irradiation is shown as well as activity of reparation processes after UV irradiation. The presence of low photoreactivating activity in P. methanolica is shown as well. Observed recovery in innutritious medium and decrease of irradiated cells survival rates under effect of reparation inhibitors (coffeine and acriflavine) testify to activity of excision reparation and, perhaps, recombination branch of postreplicative reparation. No manifestation of inducible reparation system is discovered. It is concluded that increased resistance of P. methanolica cells to bactericidal and mutagenous effects of short-wave ultraviolet radiation is related to activity of exact reparation systems

  10. Complete genome sequence of Pseudomonas azotoformans S4, a potential biocontrol bacterium.

    Science.gov (United States)

    Fang, Yang; Wu, Lijuan; Chen, Guoqing; Feng, Guozhong

    2016-06-10

    Pseudomonas azotoformans is a Gram-negative bacterium and infects cereal grains, especially rice. P. azotoformans S4 from soil sample derived from Lijiang, Yunnan Province, China, appeared to be strong inhibitory activity against Fusarium fujikurio, a serious rice fungal pathogen. Here, we present the complete genome of P. azotoformans S4, which consists of 6,859,618bp with a circle chromosome, 5991 coding DNA sequences, 70 tRNA and 19 rRNA. The genomic analysis revealed that 9 candidate gene clusters are involved in the biosynthesis of secondary metabolites. PMID:27080451

  11. Pseudomonas chloritidismutans sp. nov., a non-denitrifying chlorate-reducing bacterium

    OpenAIRE

    Wolterink, A.F.W.M.; Jonker, A.B.; Kengen, S.W.M.; Stams, A.J.M.

    2002-01-01

    A Gram-negative, facultatively anaerobic, rod-shaped, dissimilatory chlorate-reducing bacterium, strain AW-1(T), was isolated from biomass of an anaerobic chlorate-reducing bioreactor. Phylogenetic analysis of the 16S rDNA sequence showed 100␜equence similarity to Pseudomonas stutzeri DSM 50227 and 98.6␜equence similarity to the type strain of P. stutzeri (DSM 5190(T)). The species P. stutzeri possesses a high degree of genotypic and phenotypic heterogeneity. Therefore, eight genomic groups, ...

  12. Production of medium-chain-length polyhydroxyalkanoates by sequential feeding of xylose and octanoic acid in engineered Pseudomonas putida KT2440

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    Le Meur Sylvaine

    2012-08-01

    Full Text Available Abstract Background Pseudomonas putida KT2440 is able to synthesize large amounts of medium-chain-length polyhydroxyalkanoates (mcl-PHAs. To reduce the substrate cost, which represents nearly 50% of the total PHA production cost, xylose, a hemicellulose derivate, was tested as the growth carbon source in an engineered P. putida KT2440 strain. Results The genes encoding xylose isomerase (XylA and xylulokinase (XylB from Escherichia coli W3110 were introduced into P. putida KT2440. The recombinant KT2440 exhibited a XylA activity of 1.47 U and a XylB activity of 0.97 U when grown on a defined medium supplemented with xylose. The cells reached a maximum specific growth rate of 0.24 h-1 and a final cell dry weight (CDW of 2.5 g L-1 with a maximal yield of 0.5 g CDW g-1 xylose. Since no mcl-PHA was accumulated from xylose, mcl-PHA production can be controlled by the addition of fatty acids leading to tailor-made PHA compositions. Sequential feeding strategy was applied using xylose as the growth substrate and octanoic acid as the precursor for mcl-PHA production. In this way, up to 20% w w-1 of mcl-PHA was obtained. A yield of 0.37 g mcl-PHA per g octanoic acid was achieved under the employed conditions. Conclusions Sequential feeding of relatively cheap carbohydrates and expensive fatty acids is a practical way to achieve more cost-effective mcl-PHA production. This study is the first reported attempt to produce mcl-PHA by using xylose as the growth substrate. Further process optimizations to achieve higher cell density and higher productivity of mcl-PHA should be investigated. These scientific exercises will undoubtedly contribute to the economic feasibility of mcl-PHA production from renewable feedstock.

  13. Sistema para mejorar la producción de polihidroxialcanoatos (bioplástico) por fermentación a partir de glicerol utilizando una cepa de pseudomonas putida modificada genéticamente

    OpenAIRE

    Fernández Escapa, Isabel; Cerro, Carlos del; Garcia, José Luis; Prieto, María Auxiliadora

    2011-01-01

    En la presente invención se describe el diseño y realización de un procedimiento para facilitar la producción de sustancias, y en particular de polihidroxialcanoatos (PHAs), en Pseudomonas putida a partir de glicerol. A tal fin se ha construido una cepa mutante derivada de P. putida portadora de una mutación en el cromosoma del gen glpR que permite que la bacteria pueda utilizar el glicerol como fuente de carbono y energía de una manera más eficiente y por lo tanto permite mejorar la producci...

  14. In-vitro antibacterial activities of the essential oils of aromatic plants against Erwinia herbicola (Lohnis and pseudomonas putida (Kris Hamilton

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    Pandey Abhay K.

    2012-01-01

    Full Text Available This study was designed to examine in vitro antibacterial activities of essential oils extracted from 53 aromatic plants of Gorakhpur Division (UP, INDIA for the control of two phytopathogenic bacteria namely Erwinia herbicola and Pseudomonas putida causing several post-harvest diseases in fruits and vegetables. Out of 53 oils screened, 8 oils such as Chenopodium ambrosioides, Citrus aurantium, Clausena pentaphylla, Hyptis suaveolens, Lippia alba, Mentha arvensis, Ocimum sanctum and Vitex negundo completely inhibited the growth of test bacteria. Furthermore MIC & MBC values of C. ambrosioides oil were least for Erw. herbicola (0.25 & 2.0 μl/ml and Ps. putida (0.12 & 1.0 μl/ml respectively than other 7 oils as well as Agromycin and Streptomycin drugs used in current study. GC and GC-MS analysis of Chenopodium oil revealed presence of 125 major and minor compounds, out of them, 14 compounds were recognized. The findings concluded that Chenopodium oil may be regarded as safe antibacterial agent for the management of post-harvest diseases of fruits and vegetables.

  15. Crystallization and preliminary X-ray diffraction studies of the ISC-like [2Fe–2S] ferredoxin (FdxB) from Pseudomonas putida JCM 20004

    International Nuclear Information System (INIS)

    A vertebrate-type [2Fe–2S] ferredoxin (FdxB), which is probably involved in the iron–sulfur cluster-biosynthesis system of the γ-proteobacterium P. putida JCM 20004, has been crystallized in space group P6122. The needle-shaped crystals of recombinant FdxB diffract to 1.90 Å resolution using synchrotron radiation. The iron–sulfur (Fe–S) cluster-biosynthesis (ISC) system of the γ-proteobacterium Pseudomonas putida JCM 20004 contains a constitutively expressed vertebrate-type [2Fe–2S] ferredoxin, FdxB, which lacks the conserved free cysteine residue near the Fe–S cluster site that has been proposed to function in the catalysis of biological Fe–S cluster assembly in other bacterial homologues. Recombinant FdxB was heterologously overproduced in Escherichia coli, purified and crystallized in its oxidized form by the hanging-drop vapour-diffusion and streak-seeding methods using 1.6 M trisodium citrate dihydrate pH 6.5. The thin needle-shaped crystals diffract to 1.90 Å resolution and belong to the hexagonal space group P6122, with unit-cell parameters a = 87.58, c = 73.14 Å. The asymmetric unit contains one protein molecule

  16. Pseudomonas putida KT2440 markerless gene deletion using a combination of λ Red recombineering and Cre/loxP site-specific recombination.

    Science.gov (United States)

    Luo, Xi; Yang, Yunwen; Ling, Wen; Zhuang, Hao; Li, Qin; Shang, Guangdong

    2016-02-01

    Pseudomonas putida KT2440 is a saprophytic, environmental microorganism that plays important roles in the biodegradation of environmental toxic compounds and production of polymers, chemicals and secondary metabolites. Gene deletion of KT2440 usually involves cloning of the flanking homologous fragments of the gene of interest into a suicide vector followed by transferring into KT2440 via triparental conjugation. Selection and counterselection steps are then employed to generate gene deletion mutant. However, these methods are tedious and are not suitable for the manipulation of multiple genes simultaneously. Herein, a two-step, markerless gene deletion method is presented. First, homologous armsflanked loxP-neo-loxP was knocked-in to replace the gene of interest, then the kanamycin resistance marker is removed by Cre recombinase catalyzed site-specific recombination. Both two-plasmid and one-plasmid gene systems were established. MekR/PmekA regulated gene expression system was found to be suitable for tight Cre expression in one-plasmid deletion system. The straightforward, time saving and highly efficient markerless gene deletion strategy has the potential to facilitate the genetics and functional genomics study of P. putida KT2440. PMID:26802072

  17. The complete genomic sequence of lytic bacteriophage gh-1 infecting Pseudomonas putida--evidence for close relationship to the T7 group

    International Nuclear Information System (INIS)

    The genome of the lytic Pseudomonas putida bacteriophage gh-1 is linear double-stranded DNA containing 37,359 bp with 216-bp direct terminal repeats. Like other members of the T7 group, the gh-1 genome contains regions of high homology to T7 interspersed with nonhomologous regions that contain small open reading frames of unknown function. The genome shares 31 genes in common with other members of the T7 group, including RNA polymerase, and an additional 12 unique putative genes. A major difference between gh-1 and other members of this group is the absence of any open reading frames between the left direct terminal repeat and gene 1. Sequence analysis of the gh-1 genome also revealed the presence of 10 putative phage promoters with a consensus sequence similar to the promoters of T3 and phiYeO3-12 (consensus: TAAAAACCCTCACTRTGGCHSCM). P. putida mutants resistant to gh-1 were demonstrated to have an altered lipopolysaccharide structure, indicating that members of this group use lipopolysaccharide as their cellular receptor

  18. Genetically engineered Pseudomonas putida X3 strain and its potential ability to bioremediate soil microcosms contaminated with methyl parathion and cadmium.

    Science.gov (United States)

    Zhang, Rong; Xu, Xingjian; Chen, Wenli; Huang, Qiaoyun

    2016-02-01

    A multifunctional Pseudomonas putida X3 strain was successfully engineered by introducing methyl parathion (MP)-degrading gene and enhanced green fluorescent protein (EGFP) gene in P. putida X4 (CCTCC: 209319). In liquid cultures, the engineered X3 strain utilized MP as sole carbon source for growth and degraded 100 mg L(-1) of MP within 24 h; however, this strain did not further metabolize p-nitrophenol (PNP), an intermediate metabolite of MP. No discrepancy in minimum inhibitory concentrations (MICs) to cadmium (Cd), copper (Cu), zinc (Zn), and cobalt (Co) was observed between the engineered X3 strain and its host strain. The inoculated X3 strain accelerated MP degradation in different polluted soil microcosms with 100 mg MP kg(-1) dry soil and/or 5 mg Cd kg(-1) dry soil; MP was completely eliminated within 40 h. However, the presence of Cd in the early stage of remediation slightly delayed MP degradation. The application of X3 strain in Cd-contaminated soil strongly affected the distribution of Cd fractions and immobilized Cd by reducing bioavailable Cd concentrations with lower soluble/exchangeable Cd and organic-bound Cd. The inoculated X3 strain also colonized and proliferated in various contaminated microcosms. Our results suggested that the engineered X3 strain is a potential bioremediation agent showing competitive advantage in complex contaminated environments. PMID:26521245

  19. Genetic and functional characterization of the gene cluster directing the biosynthesis of putisolvin I and II in Pseudomonas putida strain PCL1445.

    Science.gov (United States)

    Dubern, Jean-Frédéric; Coppoolse, Eric R; Stiekema, Willem J; Bloemberg, Guido V

    2008-07-01

    Pseudomonas putida PCL1445 secretes two cyclic lipopeptides, putisolvin I and putisolvin II, which possess a surface-tension-reducing ability, and are able to inhibit biofilm formation and to break down biofilms of Pseudomonas species including Pseudomonas aeruginosa. The putisolvin synthetase gene cluster (pso) and its surrounding region were isolated, sequenced and characterized. Three genes, termed psoA, psoB and psoC, were identified and shown to be involved in putisolvin biosynthesis. The gene products encode the 12 modules responsible for the binding of the 12 amino acids of the putisolvin peptide moiety. Sequence data indicate that the adenylation domain of the 11th module prioritizes the recognition of Val instead of Leu or Ile and consequently favours putisolvin I production over putisolvin II. Detailed analysis of the thiolation domains suggests that the first nine modules recognize the d form of the amino acid residues while the two following modules recognize the l form and the last module the l or d form, indifferently. The psoR gene, which is located upstream of psoA, shows high similarity to luxR-type regulatory genes and is required for the expression of the pso cluster. In addition, two genes, macA and macB, located downstream of psoC were identified and shown to be involved in putisolvin production or export. PMID:18599835

  20. The complete genome sequence of the plant growth-promoting bacterium Pseudomonas sp. UW4.

    Science.gov (United States)

    Duan, Jin; Jiang, Wei; Cheng, Zhenyu; Heikkila, John J; Glick, Bernard R

    2013-01-01

    The plant growth-promoting bacterium (PGPB) Pseudomonas sp. UW4, previously isolated from the rhizosphere of common reeds growing on the campus of the University of Waterloo, promotes plant growth in the presence of different environmental stresses, such as flooding, high concentrations of salt, cold, heavy metals, drought and phytopathogens. In this work, the genome sequence of UW4 was obtained by pyrosequencing and the gaps between the contigs were closed by directed PCR. The P. sp. UW4 genome contains a single circular chromosome that is 6,183,388 bp with a 60.05% G+C content. The bacterial genome contains 5,423 predicted protein-coding sequences that occupy 87.2% of the genome. Nineteen genomic islands (GIs) were predicted and thirty one complete putative insertion sequences were identified. Genes potentially involved in plant growth promotion such as indole-3-acetic acid (IAA) biosynthesis, trehalose production, siderophore production, acetoin synthesis, and phosphate solubilization were determined. Moreover, genes that contribute to the environmental fitness of UW4 were also observed including genes responsible for heavy metal resistance such as nickel, copper, cadmium, zinc, molybdate, cobalt, arsenate, and chromate. Whole-genome comparison with other completely sequenced Pseudomonas strains and phylogeny of four concatenated "housekeeping" genes (16S rRNA, gyrB, rpoB and rpoD) of 128 Pseudomonas strains revealed that UW4 belongs to the fluorescens group, jessenii subgroup. PMID:23516524

  1. Studies of Europium(III)/NTA uptake by the pseudomonas bacterium

    International Nuclear Information System (INIS)

    One area of nuclear waste remediation that has not yet been fully explored is the use of microorganisms to stabilize and recover radionuclides and to degrade the organic component of nuclear wastes to innocuous products. The mechanisms whereby microorganisms immobilize radionuclides are not well understood. A key question to answer is whether or not lanthanides and actinides are actually metabolized or simply adsorbed on the cell membrane. Previously, it has been demonstrated that the Pseudomonas sp. bacterium is capable of surviving in a growth medium in which NTA (nitriloacetic acid) is the only source of carbon or nitrogen. Pseudomonas has been shown to metabolize NTA and complexes such as Fe(III)-NTA and Ca-NTA. The authors have initiated a similar study to examine the metabolic effects of a growth solution containing only NTA and the Eu(III)-NTA complex on a culture of Pseudomonas. A europium radiotracer placed in the growth solution is used to investigate the accumulation of Eu(III) by the bacteria

  2. The complete genome sequence of the plant growth-promoting bacterium Pseudomonas sp. UW4.

    Directory of Open Access Journals (Sweden)

    Jin Duan

    Full Text Available The plant growth-promoting bacterium (PGPB Pseudomonas sp. UW4, previously isolated from the rhizosphere of common reeds growing on the campus of the University of Waterloo, promotes plant growth in the presence of different environmental stresses, such as flooding, high concentrations of salt, cold, heavy metals, drought and phytopathogens. In this work, the genome sequence of UW4 was obtained by pyrosequencing and the gaps between the contigs were closed by directed PCR. The P. sp. UW4 genome contains a single circular chromosome that is 6,183,388 bp with a 60.05% G+C content. The bacterial genome contains 5,423 predicted protein-coding sequences that occupy 87.2% of the genome. Nineteen genomic islands (GIs were predicted and thirty one complete putative insertion sequences were identified. Genes potentially involved in plant growth promotion such as indole-3-acetic acid (IAA biosynthesis, trehalose production, siderophore production, acetoin synthesis, and phosphate solubilization were determined. Moreover, genes that contribute to the environmental fitness of UW4 were also observed including genes responsible for heavy metal resistance such as nickel, copper, cadmium, zinc, molybdate, cobalt, arsenate, and chromate. Whole-genome comparison with other completely sequenced Pseudomonas strains and phylogeny of four concatenated "housekeeping" genes (16S rRNA, gyrB, rpoB and rpoD of 128 Pseudomonas strains revealed that UW4 belongs to the fluorescens group, jessenii subgroup.

  3. 5' Untranslated region of the Pseudomonas putida WCS358 stationary phase sigma factor rpoS mRNA is involved in RpoS translational regulation.

    Science.gov (United States)

    Jovcic, Branko; Bertani, Iris; Venturi, Vittorio; Topisirovic, Ljubisa; Kojic, Milan

    2008-02-01

    The sigmas subunit of RNA polymerase is a central regulator which governs the expression of a host of stationary phase-induced and osmotically regulated genes in Gram-negative bacteria. The Pseudomonas putida rpoS gene is transcribed as a monocistronic rpoS mRNA with a 368 nucleotide-long 5' untranslated region (5' UTR). In this study, we investigate the posttranscriptional control of RpoS synthesis using rpoS-lacZ transcriptional and translational fusions consisting of the native promoter and deletions of 5' UTR or insertion into UTR. The differing activity of constructed translational fusions strongly indicated that the 5' UTR is involved in the translational regulation of RpoS expression in the stationary phase. The results obtained herein demonstrated that the structure of UTR performs an important function in the translational regulation of the rpoS gene. PMID:18337694

  4. The aromatic alcohol dehydrogenases in Pseudomonas putida N.C.I.B. 9869 grown on 3,5-xylenol and p-cresol.

    Science.gov (United States)

    Keat, M J; Hopper, D J

    1978-01-01

    Whole cells of Pseudomonas putida N.C.I.B 9869, when grown on either 3,5-xylenol or p-cresol, oxidized both m- and p-hydroxybenzyl alcohols. Two distinct NAD+-dependent m-hydroxybenzyl alcohol dehydrogenases were purified from cells grown on 3,5-xylenol. Each is active with a range of aromatic alcohols, including both m- and p-hydroxybenzyl alcohol, but differ in their relative rates with the various substrates. An NAD+-dependent alcohol dehydrogenase was also partially purified from p-cresol grown cells. This too was active with m- and p-hydroxybenzyl alcohol and other aromatic alcohols, but was not identical with either of the other two dehydrogenases. All three enzymes were unstable, but were stabilized by dithiothreitol and all were inhibited with p-chloromercuribenzoate. All were specific for NAD+ and each was shown to catalyse conversion of alcohol into aldehyde. PMID:743216

  5. Synthesis of Diblock copolymer poly-3-hydroxybutyrate -block-poly-3-hydroxyhexanoate [PHB-b-PHHx] by a β-oxidation weakened Pseudomonas putida KT2442

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    Tripathi Lakshmi

    2012-04-01

    Full Text Available Abstract Background Block polyhydroxyalkanoates (PHA were reported to be resistant against polymer aging that negatively affects polymer properties. Recently, more and more attempts have been directed to make PHA block copolymers. Diblock copolymers PHB-b-PHHx consisting of poly-3-hydroxybutyrate (PHB block covalently bonded with poly-3-hydroxyhexanoate (PHHx block were for the first time produced successfully by a recombinant Pseudomonas putida KT2442 with its β-oxidation cycle deleted to its maximum. Results The chloroform extracted polymers were characterized by nuclear magnetic resonance (NMR, thermo- and mechanical analysis. NMR confirmed the existence of diblock copolymers consisting of 58 mol% PHB as the short chain length block with 42 mol% PHHx as the medium chain length block. The block copolymers had two glass transition temperatures (Tg at 2.7°C and −16.4°C, one melting temperature (Tm at 172.1°C and one cool crystallization temperature (Tc at 69.1°C as revealed by differential scanning calorimetry (DSC, respectively. This is the first microbial short-chain-length (scl and medium-chain-length (mcl PHA block copolymer reported. Conclusions It is possible to produce PHA block copolymers of various kinds using the recombinant Pseudomonas putida KT2442 with its β-oxidation cycle deleted to its maximum. In comparison to a random copolymer poly-3-hydroxybutyrate-co-3-hydroxyhexanoate (P(HB-co-HHx and a blend sample of PHB and PHHx, the PHB-b-PHHx showed improved structural related mechanical properties.

  6. Comparative one-factor-at-a-time, response surface (statistical and bench-scale bioreactor level optimization of thermoalkaline protease production from a psychrotrophic Pseudomonas putida SKG-1 isolate

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    Singh Santosh K

    2011-12-01

    Full Text Available Abstract Background Production of alkaline protease from various bacterial strains using statistical methods is customary now-a-days. The present work is first attempt for the production optimization of a solvent stable thermoalkaline protease by a psychrotrophic Pseudomonas putida isolate using conventional, response surface methods, and fermentor level optimization. Results The pre-screening medium amended with optimized (w/v 1.0% glucose, 2.0% gelatin and 0.5% yeast extract, produced 278 U protease ml-1 at 72 h incubation. Enzyme production increased to 431 Uml-1 when Mg2+ (0.01%, w/v was supplemented. Optimization of physical factors further enhanced protease to 514 Uml-1 at pH 9.0, 25°C and 200 rpm within 60 h. The combined effect of conventionally optimized variables (glucose, yeast extract, MgSO4 and pH, thereafter predicted by response surface methodology yielded 617 U protease ml-1 at glucose 1.25% (w/v, yeast extract 0.5% (w/v, MgSO4 0.01% (w/v and pH 8.8. Bench-scale bioreactor level optimization resulted in enhanced production of 882 U protease ml-1 at 0.8 vvm aeration and 150 rpm agitation during only 48 h incubation. Conclusions The optimization of fermentation variables using conventional, statistical approaches and aeration/agitation at fermentor level resulted in ~13.5 folds increase (882 Uml-1 in protease production compared to un-optimized conditions (65 Uml-1. This is the highest level of thermoalkaline protease reported so far by any psychrotrophic bacterium.

  7. Siderophore-mediated uptake of Fe3+ by the plant growth-stimulating Pseudomonas putida strain WCS358 and by other rhizosphere microorganisms

    International Nuclear Information System (INIS)

    Under iron-limited conditions, Pseudomonas putida WCS358 produces a siderophore, pseudobactin 358, which is essential for the plant growth-stimulating ability of this strain. Cells of strain WCS358, provided that they have been grown under Fe3+ limitation, take up 55Fe3+ from the 55Fe3+-labeled pseudobactin 358 complex with Km and Vmax values of 0.23 μM and 0.14 nmol/mg of cell dry weight per min, respectively. Uptake experiments with cells treated with various metabolic inhibitors showed that this Fe3+ uptake process was dependent on the proton motive force. Furthermore, strain WCS358 was shown to be able to take up Fe3+ complexed to the siderophore of another plant-beneficial P. fluorescens strain, WCS374. The tested pathogenic rhizobacteria and rhizofungi were neither able to grow on Fe3+-deficient medium in the presence of pseudobactin 358 nor able to take up 55Fe3+ from 55Fe3+-pseudobactin 358. The same applies for three cyanide-producing Pseudomonas strains which are supposed to be representatives of the minor pathogens. These results indicate that the extraordinary ability of strain WCS358 to compete efficiently for Fe3+ is based on the fact that the pathogenic and deleterious rhizosphere microorganisms, in contrast to strain WCS358 itself, are not able to take up Fe3+ from Fe3+-pseudobactin 358 complexes

  8. Bidirectional gene sequences with similar homology to functional proteins of alkane degrading bacterium pseudomonas fredriksbergensis DNA

    International Nuclear Information System (INIS)

    The potential for two overlapping fragments of DNA from a clone of newly isolated alkanes degrading bacterium Pseudomonas frederiksbergensis encoding sequences with similar homology to two parts of functional proteins is described. One strand contains a sequence with high homology to alkanes monooxygenase (alkB), a member of the alkanes hydroxylase family, and the other strand contains a sequence with some homology to alcohol dehydrogenase gene (alkJ). Overlapping of the genes on opposite strands has been reported in eukaryotic species, and is now reported in a bacterial species. The sequence comparisons and ORFS results revealed that the regulation and the genes organization involved in alkane oxidation represented in Pseudomonas frederiksberghensis varies among the different known alkane degrading bacteria. The alk gene cluster containing homologues to the known alkane monooxygenase (alkB), and rubredoxin (alkG) are oriented in the same direction, whereas alcohol dehydrogenase (alkJ) is oriented in the opposite direction. Such genomes encode messages on both strands of the DNA, or in an overlapping but different reading frames, of the same strand of DNA. The possibility of creating novel genes from pre-existing sequences, known as overprinting, which is a widespread phenomenon in small viruses. Here, the origin and evolution of the gene overlap to bacteriophages belonging to the family Microviridae have been investigated. Such a phenomenon is most widely described in extremely small genomes such as those of viruses or small plasmids, yet here is a unique phenomenon. (author)

  9. Cold stress promoting a psychrotolerant bacterium Pseudomonas fragi P121 producing trehaloase.

    Science.gov (United States)

    Mei, Yan-Zhen; Huang, Peng-Wei; Liu, Yang; He, Wei; Fang, Wen-Wan

    2016-08-01

    A newly isolated Pseudomonas fragi P121 strain in a soil sample taken from the Arctic Circle is able to produce trehalose. The P121 strain was able to grow at temperatures ranging from 4 to 25 °C, had an optimum pH of 6.5, and an optimum salt concentration of 2 %. The P121 strain had a survival rate of 29.1 % after being repeatedly frozen and thawed five times, and a survival rate of 78.9 % when placed in physiological saline for 15 days at 20 °C after cold shock, which is far higher than the type strain Pseudomonas fragi ATCC 4973. The P121 strain could produce 2.89 g/L trehalose, which was 18.6 % of dry cell weight within 52 h in a 25 L fermention tank using the malt extract prepared from barley as medium at 15 °C, while only 11.8 % of dry cell weight at 20 °C. These results suggested that cold stress promoted the strain producing trehalose. It is the first reported cold-tolerant bacterium that produces trehalose, which may protect cells against the cold environment. PMID:27339315

  10. Comparative one-factor-at-a-time, response surface (statistical) and bench-scale bioreactor level optimization of thermoalkaline protease production from a psychrotrophic Pseudomonas putida SKG-1 isolate

    OpenAIRE

    Singh Santosh K; Singh Sanjay K; Tripathi Vinayak R; Khare Sunil K; Garg Satyendra K

    2011-01-01

    Abstract Background Production of alkaline protease from various bacterial strains using statistical methods is customary now-a-days. The present work is first attempt for the production optimization of a solvent stable thermoalkaline protease by a psychrotrophic Pseudomonas putida isolate using conventional, response surface methods, and fermentor level optimization. Results The pre-screening medium amended with optimized (w/v) 1.0% glucose, 2.0% gelatin and 0.5% yeast extract, produced 278 ...

  11. Comparative one-factor-at-a-time, response surface (statistical) and bench-scale bioreactor level optimization of thermoalkaline protease production from a psychrotrophic Pseudomonas putida SKG-1 isolate

    OpenAIRE

    Singh, Santosh K.; Singh, Sanjay K.; Tripathi, Vinayak R; Khare, Sunil K; Garg, Satyendra K

    2011-01-01

    Background Production of alkaline protease from various bacterial strains using statistical methods is customary now-a-days. The present work is first attempt for the production optimization of a solvent stable thermoalkaline protease by a psychrotrophic Pseudomonas putida isolate using conventional, response surface methods, and fermentor level optimization. Results The pre-screening medium amended with optimized (w/v) 1.0% glucose, 2.0% gelatin and 0.5% yeast extract, produced 278 U proteas...

  12. Genetic evidence that catabolites of the Entner-Doudoroff pathway signal C source repression of the sigma54 Pu promoter of Pseudomonas putida.

    Science.gov (United States)

    Velázquez, Francisco; di Bartolo, Ilaria; de Lorenzo, Víctor

    2004-12-01

    Glucose and other C sources exert an atypical form of catabolic repression on the sigma54-dependent promoter Pu, which drives transcription of an operon for m-xylene degradation encoded by the TOL plasmid pWW0 in Pseudomonas putida. We have used a genetic approach to identify the catabolite(s) shared by all known repressive C sources that appears to act as the intracellular signal that triggers downregulation of Pu. To this end, we reconstructed from genomic data the pathways for metabolism of repressor (glucose, gluconate) and nonrepressor (fructose) C sources. Since P. putida lacks fructose-6-phosphate kinase, glucose and gluconate appear to be metabolized exclusively by the Entner-Doudoroff (ED) pathway, while fructose can be channeled through the Embden-Meyerhof (EM) route. An insertion in the gene fda (encoding fructose-1,6-bisphosphatase) that forces fructose metabolism to be routed exclusively to the ED pathway makes this sugar inhibitory for Pu. On the contrary, a crc mutation known to stimulate expression of the ED enzymes causes the promoter to be less sensitive to glucose. Interrupting the ED pathway by knocking out eda (encoding 2-dehydro-3-deoxyphosphogluconate aldolase) exacerbates the inhibitory effect of glucose in Pu. These observations pinpoint the key catabolites of the ED route, 6-phosphogluconate and/or 2-dehydro-3-deoxyphosphogluconate, as the intermediates that signal Pu repression. This notion is strengthened by the observation that 2-ketogluconate, which enters the ED pathway by conversion into these compounds, is a strong repressor of the Pu promoter. PMID:15576775

  13. Metabolic Fingerprinting of Pseudomonas putida DOT-T1E Strains: Understanding the Influence of Divalent Cations in Adaptation Mechanisms Following Exposure to Toluene.

    Science.gov (United States)

    Sayqal, Ali; Xu, Yun; Trivedi, Drupad K; AlMasoud, Najla; Ellis, David I; Goodacre, Royston

    2016-01-01

    Pseudomonas putida strains can adapt and overcome the activity of toxic organic solvents by the employment of several resistant mechanisms including efflux pumps and modification to lipopolysaccharides (LPS) in their membranes. Divalent cations such as magnesium and calcium play a crucial role in the development of solvent tolerance in bacterial cells. Here, we have used Fourier transform infrared (FT-IR) spectroscopy directly on cells (metabolic fingerprinting) to monitor bacterial response to the absence and presence of toluene, along with the influence of divalent cations present in the growth media. Multivariate analysis of the data using principal component-discriminant function analysis (PC-DFA) showed trends in scores plots, illustrating phenotypic alterations related to the effect of Mg(2+), Ca(2+) and toluene on cultures. Inspection of PC-DFA loadings plots revealed that several IR spectral regions including lipids, proteins and polysaccharides contribute to the separation in PC-DFA space, thereby indicating large phenotypic response to toluene and these cations. Finally, the saturated fatty acid ratio from the FT-IR spectra showed that upon toluene exposure, the saturated fatty acid ratio was reduced, while it increased in the presence of divalent cations. This study clearly demonstrates that the combination of metabolic fingerprinting with appropriate chemometric analysis can result in practicable knowledge on the responses of important environmental bacteria to external stress from pollutants such as highly toxic organic solvents, and indicates that these changes are manifest in the bacterial cell membrane. Finally, we demonstrate that divalent cations improve solvent tolerance in P. putida DOT‑T1E strains. PMID:27128955

  14. Rationally rewiring the connectivity of the XylR/Pu regulatory node of the m-xylene degradation pathway in Pseudomonas putida.

    Science.gov (United States)

    de Las Heras, Aitor; Martínez-García, Esteban; Domingo-Sananes, Maria Rosa; Fraile, Sofia; de Lorenzo, Víctor

    2016-04-18

    The XylR/Pu regulatory node of the m-xylene biodegradation pathway of Pseudomonas putida mt-2 is one of the most intricate cases of processing internal and external cues into a single controlling element. Despite this complexity, the performance of the regulatory system is determined in vivo only by the occupation of Pu by m-xylene-activated XylR and σ(54)-RNAP. The stoichiometry between these three elements defines natural system boundaries that outline a specific functional space. This space can be expanded artificially following different strategies that involve either the increase of XylR or σ(54) or both elements at the same time (each using a different inducer). In this work we have designed a new regulatory architecture that drives the system to reach a maximum performance in response to one single input. To this end, we first explored using a simple mathematical model whether the output of the XylR/Pu node could be amended by simultaneously increasing σ(54) and XylR in response to only natural inducers. The exacerbation of Pu activity in vivo was tested in strains bearing synthetic transposons encoding xylR and rpoN (the σ(54) coding gene) controlled also by Pu, thereby generating a P. putida strain with the XylR/Pu output controlled by two intertwined feed forward loops (FFLs). The lack of a negative feedback loop in the expression node enables Pu activity to reach its physiological maximum in response to a single input. Only competition for cell resources might ultimately check the upper activity limit of such a rewired m-xylene sensing device. PMID:26961967

  15. Bacteria mediated dissolution of pyromorphite Pb5(PO4)3Cl in presence of Pseudomonas putida bacteria - an effect on Pb remobilization in the environment

    Science.gov (United States)

    Flis, Justyna; Manecki, Maciej; Merkel, Broder J.; Latowski, Dariusz

    2010-05-01

    The objective of the study was to determine the mechanisms of microbially enhanced dissolution of lead phosphate-pyromorphite Pb5(PO4)3Cl). Contrary to the current literature, the results of our experiments indicate a great potential for Pb remobilization in the environment by an aerobic microorganism acquiring phosphates. Broad knowledge exists about the role of Pb-apatites in regulating the behavior and the bioavailability of Pb in soils and wastewater. In situ Pb immobilization is one of the methods now routinely applied for the reclamation of Pb-contaminated soils, including shallow unconfined aquifers (Magalhaes & Silva, 2003; Magalhaes, 2002; Ma et al. 1993). This method is based on the principle that aqueous phosphates added to soil pore solutions form a very stable (insoluble) mineral pyromorphite (Pb-apatite) Pb5(PO4)3Cl. Bioavailability of aqueous Pb is thus minimized due to the very low solubility and the high thermodynamic stability of pyromorphite (Flis, 2007; Nriagu, 1974). Several reports have examined the ability of different bacterial species including Pseudomonas to solubilise insoluble inorganic phosphate compounds for example apatites (Welch et al., 2002; Maurice et al., 1999; Rodriguez and Fraga, 1999 ). Various species of Pseudomonas genera are encountered as common inhabitants of soils and wastes in the industrial areas under strong pollution influence. To date, there has not been any published evidence of microbial dissolution of pyromorphite. The major objective of the project was to study Pseudomonas putida growth in the presence of Pb-apatite (Pb5(PO4)3Cl) as the sole source of phosphate. It was to test the hypothesis that in the phosphate deficient environment bacteria are able to actively scavenge for P from the Pb-apatite which results in remobilization of Pb in the environment. The bacteria growth was investigated at 22oC. Commercially available Pseudomonas putida strain was used throughout. The experiment and its controls were run in

  16. Interaction between the bacterium Pseudomonas fluorescens and vermiculite: Effects on chemical, mineralogical, and mechanical properties of vermiculite

    Science.gov (United States)

    Müller, Barbara; DéFago, GenèVieve

    2006-06-01

    On an expanded and crushed vermiculite, changes in chemical, mineralogical, and rheological properties of the mineral affected by microbial activity were investigated. Determination of the water content, grain size, X-ray diffraction pattern, intercrystalline swelling with glycerol, layer charge, CEC, exchangeable cations, BET surface, and rheology provided the necessary information about the differences between pure vermiculite, vermiculite suspensions containing the nutrient medium, and vermiculite suspensions containing the nutrient medium and the bacterium Pseudomonas fluorescens strain CHA0. The aerobic bacterium Pseudomonas fluorescens causes a decrease in grain size, aggregation of vermiculite grains as evidenced by smaller BET surfaces, and enhanced viscosity of the bacteria containing slurries. Layer charge, intercrystalline swelling, and CEC were not affected by the microbial activity, nor did the bacteria count for the exchange of potassium and magnesium against sodium in the vermiculite. The microbes inhibited this exchange process during the first stage of the experiments; however, increasing run time favors the exchange as well.

  17. Siderophore-mediated uptake of Fe sup 3+ by the plant growth-stimulating Pseudomonas putida strain WCS358 and by other rhizosphere microorganisms

    Energy Technology Data Exchange (ETDEWEB)

    de Weger, L.A.; van Arendonk, J.J.C.M.; Recourt, K.; Lugtenberg, B. (Leiden Univ. (Netherlands)); van der Hofstad, G.A.J.M.; Weisbeek, P.J. (Univ. of Utrecht (Netherlands))

    1988-10-01

    Under iron-limited conditions, Pseudomonas putida WCS358 produces a siderophore, pseudobactin 358, which is essential for the plant growth-stimulating ability of this strain. Cells of strain WCS358, provided that they have been grown under Fe{sup 3+} limitation, take up {sup 55}Fe{sup 3+} from the {sup 55}Fe{sup 3+}-labeled pseudobactin 358 complex with K{sub m} and V{sub max} values of 0.23 {mu}M and 0.14 nmol/mg of cell dry weight per min, respectively. Uptake experiments with cells treated with various metabolic inhibitors showed that this Fe{sup 3+} uptake process was dependent on the proton motive force. Furthermore, strain WCS358 was shown to be able to take up Fe{sup 3+} complexed to the siderophore of another plant-beneficial P. fluorescens strain, WCS374. The tested pathogenic rhizobacteria and rhizofungi were neither able to grow on Fe{sup 3+}-deficient medium in the presence of pseudobactin 358 nor able to take up {sup 55}Fe{sub 3+} from {sup 55}Fe{sup 3+}-pseudobactin 358. The same applies for three cyanide-producing Pseudomonas strains which are supposed to be representatives of the minor pathogens. These results indicate that the extraordinary ability of strain WCS358 to compete efficiently for Fe{sup 3+} is based on the fact that the pathogenic and deleterious rhizosphere microorganisms, in contrast to strain WCS358 itself, are not able to take up Fe{sup 3+} from Fe{sup 3+}-pseudobactin 358 complexes.

  18. Numerical modelling of biophysicochemical effects on multispecies reactive transport in porous media involving Pseudomonas putida for potential microbial enhanced oil recovery application.

    Science.gov (United States)

    Sivasankar, P; Rajesh Kanna, A; Suresh Kumar, G; Gummadi, Sathyanarayana N

    2016-07-01

    pH and resident time of injected slug plays a critical role in characterizing the reservoir for potential microbial enhanced oil recovery (MEOR) application. To investigate MEOR processes, a multispecies (microbes-nutrients) reactive transport model in porous media was developed by coupling kinetic and transport model. The present work differs from earlier works by explicitly determining parametric values required for kinetic model by experimental investigations using Pseudomonas putida at different pH conditions and subsequently performing sensitivity analysis of pH, resident time and water saturation on concentrations of microbes, nutrients and biosurfactant within reservoir. The results suggest that nutrient utilization and biosurfactant production are found to be maximum at pH 8 and 7.5 respectively. It is also found that the sucrose and biosurfactant concentrations are highly sensitive to pH rather than reservoir microbial concentration, while at larger resident time and water saturation, the microbial and nutrient concentrations were lesser due to enhanced dispersion. PMID:27030954

  19. A novel Pseudomonas aeruginosa bacteriophage, Ab31, a chimera formed from temperate phage PAJU2 and P. putida lytic phage AF: characteristics and mechanism of bacterial resistance.

    Directory of Open Access Journals (Sweden)

    Libera Latino

    Full Text Available A novel temperate bacteriophage of Pseudomonas aeruginosa, phage vB_PaeP_Tr60_Ab31 (alias Ab31 is described. Its genome is composed of structural genes related to those of lytic P. putida phage AF, and regulatory genes similar to those of temperate phage PAJU2. The virion structure resembles that of phage AF and other lytic Podoviridae (S. enterica Epsilon 15 and E. coli phiv10 with similar tail spikes. Ab31 was able to infect P. aeruginosa strain PA14 and two genetically related strains called Tr60 and Tr162, out of 35 diverse strains from cystic fibrosis patients. Analysis of resistant host variants revealed different phenotypes, including induction of pigment and alginate overproduction. Whole genome sequencing of resistant variants highlighted the existence of a large deletion of 234 kbp in two strains, encompassing a cluster of genes required for the production of CupA fimbriae. Stable lysogens formed by Ab31 in strain Tr60, permitted the identification of the insertion site. During colonization of the lung in cystic fibrosis patients, P. aeruginosa adapts by modifying its genome. We suggest that bacteriophages such as Ab31 may play an important role in this adaptation by selecting for bacterial characteristics that favor persistence of bacteria in the lung.

  20. Effects of even and odd number fatty acids cofeeding on PHA production and composition in Pseudomonas putida Bet001 isolated from palm oil mill effluent.

    Science.gov (United States)

    Mohd Razaif-Mazinah, Mohd Rafais; Mohamad Annuar, Mohamad Suffian; Sharifuddin, Yusrizam

    2016-02-01

    The biosynthesis of medium-chain-length poly-3-hydroxyalkanoates by Pseudomonas putida Bet001 cultivated on mixed carbon sources was investigated. The mixed carbon sources consisted of heptanoic acid (HA) and oleic acid (OA). A relatively low PHA content at 1.2% (w/w) and 11.4% (w/w) was obtained when HA or OA was used as the sole carbon source. When these fatty acids were supplied as a mixture, PHA content increased threefold. Interestingly, the mixture-derived PHA composed of both odd and even monomer units, namely. 3-hydroxyheptanoate, 3-hydroxyoctanoate, 3-hydroxydecanoate, and 3-hydroxydodecanoate and no unsaturated monomer was detected. It is hypothesized that the even-numbered monomers were derived primarily from OA, whereas the odd-numbered monomer was derived from HA. This also points out to an efficient and yet distinct fatty acids metabolism that fed the PHA biosynthesis machinery of this particular microorganism. PHA obtained was elastomeric because melting temperature (Tm ) and crystallinity were absent. It showed good thermal stability with degradation temperature (Td ) ranging from 275.96 to 283.05 °C. PMID:25643814

  1. Production of Medium-Chain-Length Poly(3-Hydroxyalkanoates from Saponified Palm Kernel Oil by Pseudomonas putida: Kinetics of Batch and Fed-Batch Fermentations

    Directory of Open Access Journals (Sweden)

    Annuar, M. S. M.

    2006-01-01

    Full Text Available The kinetics of medium-chain-length poly(3-hydroxyalkanoates, PHAMCL production by Pseudomonas putida PGA1 in batch and fed-batch fermentations were studied. With saponified palm kernel oil (SPKO supplying the free fatty acids mixture as the sole carbon and energy source, PHAMCL accumulation is encouraged under ammonium-limited condition, which is a nitrogen stress environment. The amount of PHAMCL accumulated and its specific production rate, qPHA were influenced by the residual ammonium concentration level in the culture medium. It was observed that in both fermentation modes, when the residual ammonium was exhausted (< 0.05 gL-1, the PHAMCL accumulation (11.9% and qPHA (0.0062 h-1 were significantly reduced. However, this effect can be reversed by feeding low amount of ammonium to the culture, resulting in significantly improved PHAMCL yield (71.4% and specific productivity (0.6 h-1. It is concluded that the feeding of low ammonium concentration to the culture medium during the PHAMCL accumulation has a positive effect on sustaining the PHAMCL biosynthetic capability of the organism. It was also found that increasing SPKO concentration in the medium significantly reduced (up to 50% the volumetric oxygen transfer coefficient (KLa of the fermentation system.

  2. Toxicity of synthetic herbicides containing 2,4-D and MCPA moieties towards Pseudomonas putida mt-2 and its response at the level of membrane fatty acid composition.

    Science.gov (United States)

    Piotrowska, Aleksandra; Syguda, Anna; Chrzanowski, Łukasz; Heipieper, Hermann J

    2016-02-01

    One of the attempts to create more effective herbicidal compounds includes the use of ionic liquids. Herbicidal ionic liquids have more effective biological activity, they are less volatile, more thermally stable, and exhibit superior efficiency in comparison to typically employed herbicides, allowing the reduction of the herbicide dose applied per hectare. However, studies on the environmental toxicity of this group of compounds are very rarely available. Environmental toxicity is an important factor, showing the concentration of compounds that has negative effects on soil bacteria including those responsible for biodegradation processes. Therefore, potential toxicity of four herbicidal ionic liquids (HILs) precursors containing 2,4-D and MCPA moieties was tested with the well investigated model organism for toxicity and adaptation, Pseudomonas putida mt-2. Results were compared to those obtained for commercial 2,4-D and MCPA herbicides. Next to growth inhibition, given as EC50, changes in the isomerisation of cis to trans unsaturated fatty acids were applied as proxy for cellular stress adaptation to toxic substances. The results revealed that all investigated precursors of HILs showed lower toxicity compared to commercialized synthetic herbicides 2,4-D and MCPA. The collected data on toxicity of HILs together with their physico-chemical properties might be useful for assessing the potential risk of the environmental pollution as well as guidelines for setting the legislation for their future use. PMID:26347932

  3. In vitro transcriptional studies of the bkd operon of Pseudomonas putida: L-branched-chain amino acids and D-leucine are the inducers.

    Science.gov (United States)

    Madhusudhan, K T; Luo, J; Sokatch, J R

    1999-05-01

    BkdR is the transcriptional activator of the bkd operon, which encodes the four proteins of the branched-chain keto acid dehydrogenase multienzyme complex of Pseudomonas putida. In this study, hydroxyl radical footprinting revealed that BkdR bound to only one face of DNA over the same region identified in DNase I protection assays. Deletions of even a few bases in the 5' region of the BkdR-binding site greatly reduced transcription, confirming that the entire protected region is necessary for transcription. In vitro transcription of the bkd operon was obtained by using a vector containing the bkdR-bkdA1 intergenic region plus the putative rho-independent terminator of the bkd operon. Substrate DNA, BkdR, and any of the L-branched-chain amino acids or D-leucine was required for transcription. Branched-chain keto acids, D-valine, and D-isoleucine did not promote transcription. Therefore, the L-branched-chain amino acids and D-leucine are the inducers of the bkd operon. The concentration of L-valine required for half-maximal transcription was 2.8 mM, which is similar to that needed to cause half-maximal proteolysis due to a conformational change in BkdR. A model for transcriptional activation of the bkd operon by BkdR during enzyme induction which incorporates these results is presented. PMID:10217783

  4. The oxygenating constituent of 3,6-diketocamphane monooxygenase from the CAM plasmid of Pseudomonas putida: the first crystal structure of a type II Baeyer–Villiger monooxygenase

    Energy Technology Data Exchange (ETDEWEB)

    Isupov, Michail N.; Schröder, Ewald; Gibson, Robert P.; Beecher, Jean; Donadio, Giuliana; Saneei, Vahid; Dcunha, Stephlina A.; McGhie, Emma J.; Sayer, Christopher; Davenport, Colin F. [University of Exeter, Stocker Road, Exeter EX4 4QD (United Kingdom); Lau, Peter C. [National Research Council Canada, 6100 Royalmount Avenue, Montreal, QC H4P 2R2 (Canada); Hasegawa, Yoshie; Iwaki, Hiroaki [Kansai University (Japan); Kadow, Maria; Balke, Kathleen; Bornscheuer, Uwe T. [Greifswald University, Felix-Hausdorff-Strasse 4, 17487 Greifswald (Germany); Bourenkov, Gleb [European Molecular Biology Laboratory (EMBL), Hamburg Outstation, Notkestrasse 85, 22607 Hamburg (Germany); Littlechild, Jennifer A., E-mail: j.a.littlechild@exeter.ac.uk [University of Exeter, Stocker Road, Exeter EX4 4QD (United Kingdom)

    2015-10-31

    The first crystal structure of a type II Baeyer–Villiger monooxygenase reveals a different ring orientation of its FMN cofactor compared with other related bacterial luciferase-family enzymes. The three-dimensional structures of the native enzyme and the FMN complex of the overexpressed form of the oxygenating component of the type II Baeyer–Villiger 3,6-diketocamphane monooxygenase have been determined to 1.9 Å resolution. The structure of this dimeric FMN-dependent enzyme, which is encoded on the large CAM plasmid of Pseudomonas putida, has been solved by a combination of multiple anomalous dispersion from a bromine crystal soak and molecular replacement using a bacterial luciferase model. The orientation of the isoalloxazine ring of the FMN cofactor in the active site of this TIM-barrel fold enzyme differs significantly from that previously observed in enzymes of the bacterial luciferase-like superfamily. The Ala77 residue is in a cis conformation and forms a β-bulge at the C-terminus of β-strand 3, which is a feature observed in many proteins of this superfamily.

  5. Degradation of Reactive Black 5 dye by a newly isolated bacterium Pseudomonas entomophila BS1.

    Science.gov (United States)

    Khan, Sana; Malik, Abdul

    2016-03-01

    The textile and dye industries are considered as one of the major sources of environmental pollution. The present study was conducted to investigate the degradation of the azo dye Reactive Black 5 (RB 5) using a bacterium isolated from soil samples collected around a textile industry. The bacterial strain BS1 capable of degrading RB 5 was isolated and identified as Pseudomonas entomophila on the basis of 16S rDNA sequencing. The effects of different parameters on the degradation of RB 5 were studied to find out the optimal conditions required for maximum degradation, which was 93% after 120 h of incubation. Static conditions with pH in the range of 5-9 and a temperature of 37 °C were found to be optimum for degrading RB 5. Enzyme assays demonstrated that P. entomophila possessed azoreductase, which played an important role in degradation. The enzyme was dependent on flavin mononucleotide and NADH for its activity. Furthermore, a possible degradation pathway of the dye was proposed through gas chromatography - mass spectrometry analysis, which revealed that the metabolic products were naphthalene-1,2-diamine and 4-(methylsulfonyl) aniline. Thus the ability of this indigenous bacterial isolate for simultaneous decolorization and degradation of the azo dye signifies its potential application for treatment of industrial wastewaters containing azo dyes. PMID:26911309

  6. Three Alginate Lyases from Marine Bacterium Pseudomonas fluorescens HZJ216: Purification and Characterization

    Energy Technology Data Exchange (ETDEWEB)

    Liyan, Li [Ocean University of China, Qingdao, PRC; Jiang, Xiaolu [Ocean University of China, Qingdao, PRC; Wang, Peng [Ocean University of China, Qingdao, PRC; Guan, Huashi [Ocean University of China, Qingdao, PRC; Guo, Hong [ORNL

    2010-01-01

    Three alginate lyases (A, B, and C) from an alginate-degrading marine bacterium strain HZJ216 isolated from brown seaweed in the Yellow Sea of China and identified preliminarily as Pseudomonas fluorescens are purified, and their biochemical properties are described. Molecular masses of the three enzymes are determined by SDS-PAGE to be 60.25, 36, and 23 kDa with isoelectric points of 4, 4.36, and 4.59, respectively. Investigations of these enzymes at different pH and temperatures show that they are most active at pH 7.0 and 35 C. Alginate lyases A and B are stable in the pH range of 5.0 9.0, while alginate lyase C is stable in the pH range of 5.0 7.0. Among the metal ions tested, additions of Na+, K+, and Mg2+ ions can enhance the enzyme activities while Fe2+, Fe3+, Ba2+, and Zn2+ ions show inhibitory effects. The substrate specificity results demonstrate that alginate lyase C has the specificity for G block while alginate lyases A and B have the activities for both M and G blocks. It is the first report about extracellular alginate lyases with high alginate-degrading activity from P. fluorescens.

  7. Fusarium Wilt Suppression and Agglutinability of Pseudomonas putida†

    OpenAIRE

    Tari, P. H.; Anderson, A J

    1988-01-01

    Mutants of Pseudomonas putida (Agg−) that lack the ability to agglutinate with components present in washes of bean and cucumber roots showed limited potential to protect cucumber plants against Fusarium oxysporum f. sp. cucumerinum. However, a higher level of protection was observed against Fusarium wilt in cucumber plants coinoculated with the parental bacterium (Agg+), which was agglutinable. The Agg− mutants did not colonize the roots of cucumber plants as extensively as the Agg+ parental...

  8. HipH Catalyzes the Hydroxylation of 4-Hydroxyisophthalate to Protocatechuate in 2,4-Xylenol Catabolism by Pseudomonas putida NCIMB 9866.

    Science.gov (United States)

    Chao, Hong-Jun; Chen, Yan-Fei; Fang, Ti; Xu, Ying; Huang, Wei E; Zhou, Ning-Yi

    2016-01-01

    In addition to growing on p-cresol, Pseudomonas putida NCIMB 9866 is the only reported strain capable of aerobically growing on 2,4-xylenol, which is listed as a priority pollutant by the U.S. Environmental Protection Agency. Several enzymes involved in the oxidation of the para-methyl group, as well as the corresponding genes, have previously been reported. The enzyme catalyzing oxidation of the catabolic intermediate 4-hydroxyisophthalate to the ring cleavage substrate protocatechuate was also purified from strain NCIMB 9866, but its genetic determinant is still unavailable. In this study, the gene hipH, encoding 4-hydroxyisophthalate hydroxylase, from strain NCIMB 9866 was cloned by transposon mutagenesis. Purified recombinant HipH-His6 was found to be a dimer protein with a molecular mass of approximately 110 kDa. HipH-His6 catalyzed the hydroxylation of 4-hydroxyisophthalate to protocatechuate with a specific activity of 1.54 U mg(-1) and showed apparent Km values of 11.40 ± 3.05 μM for 4-hydroxyisophthalate with NADPH and 11.23 ± 2.43 μM with NADH and similar Km values for NADPH and NADH (64.31 ± 13.16 and 72.76 ± 12.06 μM, respectively). The identity of protocatechuate generated from 4-hydroxyisophthalate hydroxylation by HipH-His6 has also been confirmed by high-performance liquid chromatography and mass spectrometry. Gene transcriptional analysis, gene knockout, and complementation indicated that hipH is essential for 2,4-xylenol catabolism but not for p-cresol catabolism in this strain. This fills a gap in our understanding of the gene that encodes a critical step in 2,4-xylenol catabolism and also provides another example of biochemical and genetic diversity of microbial catabolism of structurally similar compounds. PMID:26567311

  9. Potential DNA slippage structures acquired during evolutionary divergence of Acinetobacter calcoaceticus chromosomal benABC and Pseudomonas putida TOL pWW0 plasmid xylXYZ, genes encoding benzoate dioxygenases.

    Science.gov (United States)

    Harayama, S; Rekik, M; Bairoch, A; Neidle, E L; Ornston, L N

    1991-01-01

    The xylXYZ DNA region is carried on the TOL pWW0 plasmid in Pseudomonas putida and encodes a benzoate dioxygenase with broad substrate specificity. The DNA sequence of the region is presented and compared with benABC, the chromosomal region encoding the benzoate dioxygenase of Acinetobacter calcoaceticus. Corresponding genes from the two biological sources share common ancestry: comparison of aligned XylX-BenA, XylY-BenB, and XylZ-BenC amino acid sequences revealed respective identities of 58.3, 61.3, and 53%. The aligned genes have diverged to assume G+C contents that differ by 14.0 to 14.9%. Usage of the unusual arginine codons AGA and AGG appears to have been selected in the P. putida xylX gene as it diverged from the ancestor it shared with A. calcoaceticus benA. Homologous A. calcoaceticus and P. putida genes exhibit different patterns of DNA sequence repetition, and analysis of one such pattern suggests that mutations creating different DNA slippage structures made a significant contribution to the evolutionary divergence of xylX. PMID:1938949

  10. Catabolism of caffeine and purification of a xanthine oxidade responsible for methyluric acids production in Pseudomonas putida L Catabolismo de cafeína e purificação de xantina oxidase responsável pela produção de ácidos metilúricos em Pseudomonas putida L

    Directory of Open Access Journals (Sweden)

    Dirce Mithico Yamaoka-Yano

    1999-01-01

    Full Text Available Caffeine catabolism and a xanthine oxidase involved in the alkaloid breakdown were studied in Pseudomonas putida L, a strain displaying high ability to grow on this substrate. Cells cultured with unlabelled caffeine and 14C labeled caffeine and xanthine showed that this alkaloid was broken-down via theobromine/paraxanthine -> 7-methylxanthine -> xanthine -> uric acid -> allantoin -> allantoic acid. Methyluric acids were formed from the oxidation of theobromine, paraxanthine and 7-methylxanthine, although no bacterial growth was observed on these compounds, indicating that this might be due to a wide substrate specificity of xanthine oxidase. This was confirmed by activity staining in PAGE where activity was observed with theophylline and 3-methylxanthine, which are not involved in the alkaloid breakdown. A single band of activity was detected without addition of NAD+, showing an oxidase form of the enzyme. The enzyme optimum temperature and pH were 30oC and 7.0, respectively. The determined Km was 169 µM, and the pI 3.1 - 4.0. The molecular weight determined by side by side comparison of activity staining of the enzyme in PAGE and PAGE of BSA was 192 kDa, which was coincident with the sum (198.4 kDa of three subunits (71, 65.6 and 61.8 kDa of the purified protein.O catabolismo de cafeína e a enzima xantina oxidase, envolvida na sua degradação, foram estudados em Pseudomonas putida L, uma linhagem com alta capacidade para utilizar este substrato como fonte de energia. Células crescidas na presença de cafeína e xantina marcadas com 14C, e cafeína não marcada, mostraram que este alcalóide foi degradado via teobromina/paraxantina -> 7-metilxantina -> xantina -> ácido úrico -> alantoína -> ácido alantóico. Ácidos metilúricos foram formados a partir de teobromina, paraxantina e 7-metilxantina, embora nenhum crescimento bacteriano ter sido observado quando estes compostos foram usados como substratos, indicando que a xantina oxidase

  11. Crystal structures of complexes of NAD+-dependent formate dehydrogenase from methylotrophic bacterium Pseudomonas sp. 101 with formate

    International Nuclear Information System (INIS)

    Formate dehydrogenase (FDH) from the methylotrophic bacterium Pseudomonas sp. 101 catalyzes oxidation of formate to NI2 with the coupled reduction of nicotinamide adenine dinucleotide (NAD+). The three-dimensional structures of the apo form (the free enzyme) and the holo form (the ternary FDH-NAD+-azide complex) of FDH have been established earlier. In the present study, the structures of FDH complexes with formate are solved at 2.19 and 2.28 A resolution by the molecular replacement method and refined to the R factors of 22.3 and 20.5%, respectively. Both crystal structures contain four protein molecules per asymmetric unit. These molecules form two dimers identical to the dimer of the apo form of FDH. Two possible formatebinding sites are found in the active site of the FDH structure. In the complexes the sulfur atom of residue Cys354 exists in the oxidized state

  12. Binary combination of epsilon-poly-L-lysine and isoeugenol affect progression of spoilage microbiota in fresh turkey meat, and delay onset of spoilage in Pseudomonas putida challenged meat.

    Science.gov (United States)

    Hyldgaard, Morten; Meyer, Rikke L; Peng, Min; Hibberd, Ashley A; Fischer, Jana; Sigmundsson, Arnar; Mygind, Tina

    2015-12-23

    Proliferation of microbial population on fresh poultry meat over time elicits spoilage when reaching unacceptable levels, during which process slime production, microorganism colony formation, negative organoleptic impact and meat structure change are observed. Spoilage organisms in raw meat, especially Gram-negative bacteria can be difficult to combat due to their cell wall composition. In this study, the natural antimicrobial agents ε-poly-L-lysine (ε-PL) and isoeugenol were tested individually and in combinations for their activities against a selection of Gram-negative strains in vitro. All combinations resulted in additive interactions between ε-PL and isoeugenol towards the bacteria tested. The killing efficiency of different ratios of the two antimicrobial agents was further evaluated in vitro against Pseudomonas putida. Subsequently, the most efficient ratio was applied to a raw turkey meat model system which was incubated for 96 h at spoilage temperature. Half of the samples were challenged with P. putida, and the bacterial load and microbial community composition was followed over time. CFU counts revealed that the antimicrobial blend was able to lower the amount of viable Pseudomonas spp. by one log compared to untreated samples of challenged turkey meat, while the single compounds had no effect on the population. However, the compounds had no effect on Pseudomonas spp. CFU in unchallenged meat. Next-generation sequencing offered culture-independent insight into population diversity and changes in microbial composition of the meat during spoilage and in response to antimicrobial treatment. Spoilage of unchallenged turkey meat resulted in decreasing species diversity over time, regardless of whether the samples received antimicrobial treatment. The microbiota composition of untreated unchallenged meat progressed from a Pseudomonas spp. to a Pseudomonas spp., Photobacterium spp., and Brochothrix thermosphacta dominated food matrix on the expense of low

  13. Responses of a soil bacterium, Pseudomonas chlororaphis O6 to commercial metal oxide nanoparticles compared with responses to metal ions

    International Nuclear Information System (INIS)

    The toxicity of commercially-available CuO and ZnO nanoparticles (NPs) to pathogenic bacteria was compared for a beneficial rhizosphere isolate, Pseudomonas chlororaphis O6. The NPs aggregated, released ions to different extents under the conditions used for bacterial exposure, and associated with bacterial cell surface. Bacterial surface charge was neutralized by NPs, dependent on pH. The CuO NPs were more toxic than the ZnO NPs. The negative surface charge on colloids of extracellular polymeric substances (EPS) was reduced by Cu ions but not by CuO NPs; the EPS protected cells from CuO NPs-toxicity. CuO NPs-toxicity was eliminated by a Cu ion chelator, suggesting that ion release was involved. Neither NPs released alkaline phosphatase from the cells' periplasm, indicating minimal outer membrane damage. Accumulation of intracellular reactive oxygen species was correlated with CuO NPs lethality. Environmental deposition of NPs could create niches for ion release, with impacts on susceptible soil microbes. - Highlights: → Toxicity of metallic nanoparticles (NPs) was evaluated in a beneficial bacterium, Pseudomonas chlororaphis O6 (PcO6). → Aggregated commercial CuO and ZnO NPs released Cu and Zn ions and changed bacterial surface charge, depending on pH. → The NPs were toxic to PcO6 through NP-specific, but also ion release mechanisms. → Reactive oxygen species were produced by CuO NP and Cu ion at lethal concentrations, but bacterial EPS protected against Cu. → The periplasmic marker, alkaline phosphate, activity was increased by the NPs and ions. - Aggregated CuO and ZnO nanoparticles release ions and cause different toxicities in a beneficial soil bacterium.

  14. Identification and characterization of an N-acylhomoserine lactone-dependent quorum-sensing system in Pseudomonas putida strain IsoF

    DEFF Research Database (Denmark)

    Steidle, A.; Allesen-Holm, M.; Riedel, K.;

    2002-01-01

    cloned a genomic region of the plant growth-promoting P. putida strain IsoF that, when present in trans, provoked induction of a bioluminescent AHL reporter plasmid. Sequence analysis identified a gene cluster consisting of four genes: ppuI and ppuR, whose predicted amino acid sequences are highly...

  15. Description of Pseudomonas gregormendelii sp. nov., a Novel Psychrotrophic Bacterium from James Ross Island, Antarctica.

    Science.gov (United States)

    Kosina, Marcel; Švec, Pavel; Černohlávková, Jitka; Barták, Miloš; Snopková, Kateřina; De Vos, Paul; Sedláček, Ivo

    2016-07-01

    During the microbiological research performed within the scope of activities of Czech expeditions based at the Johann Gregor Mendel Station at James Ross Island, Antarctica, two psychrotrophic gram-stain negative non-fluorescent strains CCM 8506T and CCM 8507 from soil were extensively characterized using genotypic and phenotypic methods. Initial characterization using ribotyping with HindIII restriction endonuclease and phenotyping implies that both isolates belong to a single Pseudomonas species. Sequencing of rrs, rpoB, rpoD and glnA genes of strain CCM 8506(T) confirmed affiliation of investigated strains within the genus Pseudomonas. Further investigation using automated ribotyping with EcoRI (RiboPrinter(®) Microbial Characterisation System), whole-cell protein profiling using the Agilent 2100 Bioanalyzer system, extensive biochemical testing and DNA-DNA hybridization experiments confirmed that both investigated strains are members of a single taxon which is clearly separated from all hitherto described Pseudomonas spp. Based on all findings, we describe a novel species Pseudomonas gregormendelii sp. nov. with the type strain CCM 8506(T) (=LMG 28632T). PMID:27032403

  16. Draft Genome Sequence of Se(IV)-Reducing Bacterium Pseudomonas migulae ES3-33

    DEFF Research Database (Denmark)

    Li, Xuanji; Kot, Witold; Wang, Dan;

    2015-01-01

    Pseudomonas migulae ES3-33 is a Gram-negative strain that strongly reduces Se(IV) and was isolated from a selenium mining area in Enshi, southwest China. Here we present the draft genome of this strain containing potential genes involved in selenite reduction and a large number of genes encoding ...

  17. No apparent costs for facultative antibiotic production by the soil bacterium Pseudomonas fluorescens Pf0-1.

    Directory of Open Access Journals (Sweden)

    Paolina Garbeva

    Full Text Available BACKGROUND: Many soil-inhabiting bacteria are known to produce secondary metabolites that can suppress microorganisms competing for the same resources. The production of antimicrobial compounds is expected to incur fitness costs for the producing bacteria. Such costs form the basis for models on the co-existence of antibiotic-producing and non-antibiotic producing strains. However, so far studies quantifying the costs of antibiotic production by bacteria are scarce. The current study reports on possible costs, for antibiotic production by Pseudomonas fluorescens Pf0-1, a soil bacterium that is induced to produce a broad-spectrum antibiotic when it is confronted with non-related bacterial competitors or supernatants of their cultures. METHODOLOGY AND PRINCIPAL FINDINGS: We measured the possible cost of antibiotic production for Pseudomonas fluorescens Pf0-1 by monitoring changes in growth rate with and without induction of antibiotic production by supernatant of a bacterial competitor, namely Pedobacter sp.. Experiments were performed in liquid as well as on semi-solid media under nutrient-limited conditions that are expected to most clearly reveal fitness costs. Our results did not reveal any significant costs for production of antibiotics by Pseudomonas fluorescens Pf0-1. Comparison of growth rates of the antibiotic-producing wild-type cells with those of non-antibiotic producing mutants did not reveal costs of antibiotic production either. SIGNIFICANCE: Based on our findings we propose that the facultative production of antibiotics might not be selected to mitigate metabolic costs, but instead might be advantageous because it limits the risk of competitors evolving resistance, or even the risk of competitors feeding on the compounds produced.

  18. Evolutionary History of the phl Gene Cluster in the Plant-Associated Bacterium Pseudomonas fluorescens▿ †

    OpenAIRE

    Moynihan, J.A.; Morrissey, J P; Coppoolse, E.; Stiekema, W. J.; O'Gara, F.; Boyd, E F

    2009-01-01

    Pseudomonas fluorescens is of agricultural and economic importance as a biological control agent largely because of its plant-association and production of secondary metabolites, in particular 2, 4-diacetylphloroglucinol (2, 4-DAPG). This polyketide, which is encoded by the eight gene phl cluster, has antimicrobial effects on phytopathogens, promotes amino acid exudation from plant roots, and induces systemic resistance in plants. Despite its importance, 2, 4-DAPG production is limited to a s...

  19. Pseudomonas yamanorum sp. nov., a psychrotolerant bacterium isolated from a subantarctic environment.

    Science.gov (United States)

    Arnau, Víctor Gonzalo; Sánchez, Leandro Arturo; Delgado, Osvaldo Daniel

    2015-02-01

    A psychrotolerant strain, 8H1(T), was isolated from soil samples collected in Isla de los Estados, Ushuaia, Argentina. Cells were Gram-negative, aerobic, straight rods, occurring singly or in pairs, non-spore-forming and motile by means of two polar flagella. The isolate was able to grow in the range 4-35 °C, with optimum growth at 28 °C. The predominant cellular fatty acids were summed feature 3 (C16 : 1ω6c and/or C16 : 1ω7c), C16 : 0 and summed feature 8 (C18 : 1ω6c and/or C18 : 1ω7c). The polar lipid pattern of strain 8H1(T) comprised phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine and an unknown phospholipid. Ubiquinone 9 (Q-9) was the predominant lipoquinone. The DNA G+C content was 59.8 mol%. 16S rRNA gene sequence-based phylogeny suggested the affiliation of strain 8H1(T) to the 'Pseudomonas fluorescens group', displaying ≥98.5 % sequence similarity to 29 type strains. A multilocus sequence analysis (MLSA) study performed by concatenating 16S rRNA, gyrB, rpoD and rpoB gene sequences showed that isolate 8H1(T) could be discriminated from closely related species of the genus Pseudomonas and placed in the 'Pseudomonas gessardii subgroup', including the species with the highest MLSA sequence similarities: Pseudomonas brenneri (96.2 %), P. gessardii (96.1 %), P. proteolytica (96.0 %), P. meridiana (96.0 %) and P. mucidolens (95.4 %). DNA-DNA hybridization analysis between 8H1(T) and the type strains of these closely related species revealed relatedness values of 27.0, 8.8, 41.2, 39.7 and 46.1 %, respectively. These results, together with differences in several phenotypic features, support the classification of a novel species, for which the name Pseudomonas yamanorum sp. nov. is proposed. The type strain is 8H1(T) ( = DSM 26522(T) = CCUG 63249(T) = LMG 27247(T)). PMID:25385990

  20. Soil components mitigate the antimicrobial effects of silver nanoparticles towards a beneficial soil bacterium, Pseudomonas chlororaphis O6

    International Nuclear Information System (INIS)

    Silver nanoparticles (Ag NPs) are widely used for their antimicrobial activity and consequently the particles will become environmental contaminants. This study evaluated in sand and soil matrices the toxicity of 10 nm spherical Ag NPs (1 and 3 mg Ag/L) toward a beneficial soil bacterium, Pseudomonas chlororaphis O6. In sand, both NP doses resulted in loss in bacterial culturability whereas in a loam soil, no cell death was observed. Amendments of sand with clays (30% v/v kaolinite or bentonite) did not protect the bacterium when challenged with Ag NPs. However, culturability of the bacterium was maintained when the Ag NP-amended sand was mixed with soil pore water or humic acid. Imaging by atomic force microscopy revealed aggregation of single nanoparticles in water, and their embedding into background material when suspended in pore water and humic acids. Zeta potential measurements supported aggregation and surface charge modifications with pore water and humic acids. Measurement of soluble Ag in the microcosms and geochemical modeling to deduce the free ion concentration revealed bacterial culturability was governed by the predicted free Ag ion concentrations. Our study confirmed the importance of Ag NPs as a source of ions and illustrated that processes accounting for protection in soil against Ag NPs involved distinct NP- and ion-effects. Processes affecting NP bioactivity involved surface charge changes due to sorption of Ca2+ from the pore water leading to agglomeration and coating of the NPs with humic acid and other organic materials. Removal of bioactive ions included the formation of soluble Ag complexes with dissolved organic carbon and precipitation of Ag ions with chloride in pore water. We conclude that mitigation of toxicity of Ag NPs in soils towards a soil bacterium resides in several interactions that differentially involve protection from the Ag NPs or the ions they produce. - Highlights: ► Silver nanoparticles (Ag NPs) are widely used for

  1. Comparison of mcl-Poly(3-hydroxyalkanoates) synthesis by different Pseudomonas putida strains from crude glycerol: citrate accumulates at high titer under PHA-producing conditions

    OpenAIRE

    Poblete-Castro, Ignacio; Binger, Danielle; Oehlert, Rene; Rohde, Manfred

    2014-01-01

    Background Achieving a sustainable society requires, among other things, the use of renewable feedstocks to replace chemicals obtained from petroleum-derived compounds. Crude glycerol synthesized inexpensively as a byproduct of biodiesel production is currently considered a waste product, which can potentially be converted into value-added compounds by bacterial fermentation. This study aimed at evaluating several characterized P. putida strains to produce medium-chain-length poly(3-hydroxyal...

  2. Equilibrium and thermodynamic parameters of single and binary mixture biosorption of lead (II) and copper (II) ions onto Pseudomonas putida: Effect of temperature

    International Nuclear Information System (INIS)

    The biosorption of lead (II) and copper (II) ions, single component and binary systems, by dried P. putida was investigated in a batch system. The effects of initial pH, temperature, initial single and binary mixture concentrations on the biosorption kinetics and equilibrium uptake of each component, both single and binary mixtures were investigated. The bacterial biomass exhibited the highest single and binary lead (II) and copper (II) ions uptake capacity at 25 and 30 deg. C, respectively, the initial pH value of 5.5 and at the initial metal ions concentration of 100 mg dm-3. The Freundlich and Langmuir adsorption models were used for the mathematical description of the biosorption equilibrium and isotherm constants were evaluated at different temperatures. Adsorption data were well described by the Langmuir model, although they could be modeled by the Freundlich equation. The thermodynamics constants of the adsorption process: ΔHo, ΔSo and ΔGo were evaluated. The results showed that biosorption of single and binary lead (II) ions on P. putida were exothermic and spontaneous. While biosorption of single and binary copper (II) ions on P. putida was endothermic and spontaneous

  3. Extracellular thermostable proteolytic activity of the milk spoilage bacterium Pseudomonas fluorescens PS19 on bovine caseins.

    Science.gov (United States)

    Stuknytė, M; Decimo, M; Colzani, M; Silvetti, T; Brasca, M; Cattaneo, S; Aldini, G; De Noni, I

    2016-06-01

    We studied the thermostable proteolytic activity of Pseudomonas fluorescens PS19 isolated from raw bovine milk. The heat-treated cell-free supernatant (HT-CFS) contained a thermostable protease of approximately 45 kDa, as revealed by casein zymography. We assigned this enzyme to P. fluorescens AprX metalloprotease (UniProtKB Acc. No. C9WKP6). After concentration by ultrafiltration at 10 kDa, the HT-CFS showed 2 other thermostable proteolytic bands on zymogram, with molecular masses of approximately 15 and 25 kDa. The former resulted a fragment of the AprX protease, whereas the 25-kDa protease was not homologous to any known protein of Pseudomonas spp. Subsequently, we assessed the proteolytic activity of the HT-CFS on bovine αS-, β-, and κ-casein during in vitro incubation at 7 or 22°C. By means of ultra-performance liquid chromatography-tandem mass spectrometry we identified the released peptides (n=591). Some of them resisted proteolysis during the whole incubation period at both incubation temperatures and, therefore, they could be assumed as indicators of the proteolytic action of P. fluorescens PS19 on bovine caseins. PMID:26995139

  4. Does S-metolachlor affect the performance of Pseudomonas sp. strain ADP as bioaugmentation bacterium for atrazine-contaminated soils?

    Directory of Open Access Journals (Sweden)

    Cristina A Viegas

    Full Text Available Atrazine (ATZ and S-metolachlor (S-MET are two herbicides widely used, often as mixtures. The present work examined whether the presence of S-MET affects the ATZ-biodegradation activity of the bioaugmentation bacterium Pseudomonas sp. strain ADP in a crop soil. S-MET concentrations were selected for their relevance in worst-case scenarios of soil contamination by a commercial formulation containing both herbicides. At concentrations representative of application of high doses of the formulation (up to 50 µg g(-1 of soil, corresponding to a dose approximately 50× higher than the recommended field dose (RD, the presence of pure S-MET significantly affected neither bacteria survival (~10(7 initial viable cells g(-1 of soil nor its ATZ-mineralization activity. Consistently, biodegradation experiments, in larger soil microcosms spiked with 20× or 50 × RD of the double formulation and inoculated with the bacterium, revealed ATZ to be rapidly (in up to 5 days and extensively (>96% removed from the soil. During the 5 days, concentration of S-MET decreased moderately to about 60% of the initial, both in inoculated and non-inoculated microcosms. Concomitantly, an accumulation of the two metabolites S-MET ethanesulfonic acid and S-MET oxanilic acid was found. Despite the dissipation of almost all the ATZ from the treated soils, the respective eluates were still highly toxic to an aquatic microalgae species, being as toxic as those from the untreated soil. We suggest that this high toxicity may be due to the S-MET and/or its metabolites remaining in the soil.

  5. Novel rhamnolipid biosurfactants produced by a polycyclic aromatic hydrocarbon-degrading bacterium Pseudomonas aeruginosa strain NY3.

    Science.gov (United States)

    Nie, Maiqian; Yin, Xihou; Ren, Chunyan; Wang, Yang; Xu, Feng; Shen, Qirong

    2010-01-01

    A novel rhamnolipid biosurfactant-producing and Polycyclic Aromatic Hydrocarbon (PAH)-degrading bacterium Pseudomonas aeruginosa strain NY3 was isolated from petroleum-contaminated soil samples. Strain NY3 was characterized by its extraordinary capacity to produce structurally diverse rhamnolipids. A total of 25 rhamnolipid components and 37 different parent molecular ions, representing various metal ion adducts (Na(+), 2Na(+) and K(+)), were detected by matrix-assisted laser desorption ionization time-of-flight mass spectrometry. Among these compounds are ten new rhamnolipids. In addition to its biosurfactant production, strain NY3 was shown to be capable of efficient degradation of PAHs as well as synergistic improvement in the degradation of high molecular weight PAHs by its biosurfactant. These findings have added novel members to the rhamnolipid group and expanded current knowledge regarding the diversity and productive capability of rhamnolipid biosurfactants from a single specific strain with variation of only one carbon source. Additionally, this paper lays the foundation for improvement in the yield of NY3BS and study of the degradation pathway(s) of PAHs in P. aeruginosa strain NY3. PMID:20580808

  6. Characterization and biodegradation kinetics of a new cold-adapted carbamazepine-degrading bacterium, Pseudomonas sp. CBZ-4.

    Science.gov (United States)

    Li, Ang; Cai, Rui; Di, Cui; Qiu, Tian; Pang, Changlong; Yang, Jixian; Ma, Fang; Ren, Nanqi

    2013-11-01

    Carbamazepine is frequently detected in waters and hardly eliminated during conventional wastewater treatment processes due to its complicated chemical structure and resistance to biodegradation. A carbamazepine-degrading bacterium named CBZ-4 was isolated at a low temperature (10 degreeC) from activated sludge in a municipal wastewater treatment plant. Strain CBZ-4, which can use carbamazepine as its sole source of carbon and energy, was identified as Pseudomonas sp. by the 16S rRNA gene sequence. The composition and percentage of fatty acids, which can reveal the cold-adaptation mechanism of strain CBZ-4, were determined. Strain CBZ-4 can effectively degrade carbamazepine at optimal conditions: pH 7.0, 10 degreeC, 150 r/min rotation speed, and 13% inoculation volume. The average removal rate of carbamazepine was 46.6% after 144 hr of incubation. The biodegradation kinetics of carbamazepine by CBZ-4 was fitted via the Monod model. Vmax and Ks were found to be 0.0094 hr-1 and 32.5 mg/L, respectively. PMID:24552057

  7. Comprehensive proteomic analysis of canola leaf inoculated with a plant growth-promoting bacterium, Pseudomonas fluorescens, under salt stress.

    Science.gov (United States)

    Banaei-Asl, Farzad; Farajzadeh, Davoud; Bandehagh, Ali; Komatsu, Setsuko

    2016-09-01

    Plant growth-promoting bacteria can improve the tolerance of canola to salt stress. To better understand the effects of plant growth-promoting bacterium on the protein profiles of canola under salt stress condition, proteomics was performed. Salt-sensitive (Sarigol) and -tolerant (Hyola308) canola cultivars were inoculated with Pseudomonas fluorescens FY32, and the protein profiles of canola leaves were compared using a PEG-fractionation method. Cluster analysis of canola cultivars based on a stress tolerance index of several morphological parameters was used to confirm that Sarigol and Hyola308 were salt-sensitive and -tolerant cultivars, respectively. Using a gel-free proteomic technique, 154 and 94 proteins in Hyola308 and 100 and 144 proteins in Sarigol were uniquely identified in non-inoculated and bacterial-inoculated cultivars, respectively. By PEG fractionation, a total of 132 and 207 proteins were identified in non-inoculated and inoculated Hyola308, respectively. Notably, the abundance of copper/zinc superoxide dismutase 1 was significantly increased in inoculated Hyola308 under severe salt stress and decreased under moderate salt stress. In addition, the enzyme activity of delta-1-pyrroline-5-carboxylate synthase was significantly increased non-inoculated Hyola308 and the activity of succinate dehydrogenase was increased in inoculated Hyola308 leaves exposed to salt stress. Taken together, these results suggest that the bacterial inoculation of canola increases salt tolerance by inducing an increase in the abundance of proteins related to glycolysis, tricarboxylic acid cycle, and amino acid metabolism. PMID:27137672

  8. Simultaneous heterotrophic nitrification and aerobic denitrification by the marine origin bacterium Pseudomonas sp. ADN-42.

    Science.gov (United States)

    Jin, Ruofei; Liu, Tianqi; Liu, Guangfei; Zhou, Jiti; Huang, Jianyu; Wang, Aijie

    2015-02-01

    Recent research has highlighted the existence of some bacteria that are capable of performing heterotrophic nitrification and have a phenomenal ability to denitrify their nitrification products under aerobic conditions. A high-salinity-tolerant strain ADN-42 was isolated from Hymeniacidon perleve and found to display high heterotrophic ammonium removal capability. This strain was identified as Pseudomonas sp. via 16S rRNA gene sequence analysis. Gene cloning and sequencing analysis indicated that the bacterial genome contains N2O reductase function (nosZ) gene. NH3-N removal rate of ADN-42 was very high. And the highest removal rate was 6.52 mg/L · h in the presence of 40 g/L NaCl. Under the condition of pure oxygen (DO >8 mg/L), NH3-N removal efficiency was 56.9 %. Moreover, 38.4 % of oxygen remained in the upper gas space during 72 h without greenhouse gas N2O production. Keeping continuous and low level of dissolved oxygen (DO <3 mg/L) was helpful for better denitrification performance. All these results indicated that the strain has heterotrophic nitrification and aerobic denitrification abilities, which guarantee future application in wastewater treatment. PMID:25432342

  9. Impact of a Recombinant Biocontrol Bacterium, Pseudomonas fluorescens pc78, on Microbial Community in Tomato Rhizosphere

    Science.gov (United States)

    Kong, Hyun Gi; Kim, Nam Hee; Lee, Seung Yeup; Lee, Seon-Woo

    2016-01-01

    Pseudomonas fluorescens pc78 is an effective biocontrol agent for soil-borne fungal diseases. We previously constructed a P43-gfp tagged biocontrol bacteria P. fluorescens pc78-48 to investigate bacterial traits in natural ecosystem and the environmental risk of genetically modified biocontrol bacteria in tomato rhizosphere. Fluctuation of culturable bacteria profile, microbial community structure, and potential horizontal gene transfer was investigated over time after the bacteria treatment to the tomato rhizosphere. Tagged gene transfer to other organisms such as tomato plants and bacteria cultured on various media was examined by polymerase chain reaction, using gene specific primers. Transfer of chromosomally integrated P43-gfp from pc78 to other organisms was not apparent. Population and colony types of culturable bacteria were not significantly affected by the introduction of P. fluorescens pc78 or pc78-48 into tomato rhizosphere. Additionally, terminal restriction fragment length polymorphism profiles were investigated to estimate the influence on the microbial community structure in tomato rhizosphere between non-treated and pc78-48-treated samples. Interestingly, rhizosphere soil treated with strain pc78-48 exhibited a significantly different bacterial community structure compared to that of non-treated rhizosphere soil. Our results suggest that biocontrol bacteria treatment influences microbial community in tomato rhizosphere, while the chromosomally modified biocontrol bacteria may not pose any specific environmental risk in terms of gene transfer. PMID:27147933

  10. Impact of a Recombinant Biocontrol Bacterium, Pseudomonas fluorescens pc78, on Microbial Community in Tomato Rhizosphere

    Directory of Open Access Journals (Sweden)

    Hyun Gi Kong

    2016-04-01

    Full Text Available Pseudomonas fluorescens pc78 is an effective biocontrol agent for soil-borne fungal diseases. We previously constructed a P43-gfp tagged biocontrol bacteria P. fluorescens pc78-48 to investigate bacterial traits in natural ecosystem and the environmental risk of genetically modified biocontrol bacteria in tomato rhizosphere. Fluctuation of culturable bacteria profile, microbial community structure, and potential horizontal gene transfer was investigated over time after the bacteria treatment to the tomato rhizosphere. Tagged gene transfer to other organisms such as tomato plants and bacteria cultured on various media was examined by polymerase chain reaction, using gene specific primers. Transfer of chromosomally integrated P43-gfp from pc78 to other organisms was not apparent. Population and colony types of culturable bacteria were not significantly affected by the introduction of P. fluorescens pc78 or pc78-48 into tomato rhizosphere. Additionally, terminal restriction fragment length polymorphism profiles were investigated to estimate the influence on the microbial community structure in tomato rhizosphere between non-treated and pc78-48-treated samples. Interestingly, rhizosphere soil treated with strain pc78-48 exhibited a significantly different bacterial community structure compared to that of non-treated rhizosphere soil. Our results suggest that biocontrol bacteria treatment influences microbial community in tomato rhizosphere, while the chromosomally modified biocontrol bacteria may not pose any specific environmental risk in terms of gene transfer.

  11. Impact of a Recombinant Biocontrol Bacterium, Pseudomonas fluorescens pc78, on Microbial Community in Tomato Rhizosphere.

    Science.gov (United States)

    Kong, Hyun Gi; Kim, Nam Hee; Lee, Seung Yeup; Lee, Seon-Woo

    2016-04-01

    Pseudomonas fluorescens pc78 is an effective biocontrol agent for soil-borne fungal diseases. We previously constructed a P43-gfp tagged biocontrol bacteria P. fluorescens pc78-48 to investigate bacterial traits in natural ecosystem and the environmental risk of genetically modified biocontrol bacteria in tomato rhizosphere. Fluctuation of culturable bacteria profile, microbial community structure, and potential horizontal gene transfer was investigated over time after the bacteria treatment to the tomato rhizosphere. Tagged gene transfer to other organisms such as tomato plants and bacteria cultured on various media was examined by polymerase chain reaction, using gene specific primers. Transfer of chromosomally integrated P43-gfp from pc78 to other organisms was not apparent. Population and colony types of culturable bacteria were not significantly affected by the introduction of P. fluorescens pc78 or pc78-48 into tomato rhizosphere. Additionally, terminal restriction fragment length polymorphism profiles were investigated to estimate the influence on the microbial community structure in tomato rhizosphere between non-treated and pc78-48-treated samples. Interestingly, rhizosphere soil treated with strain pc78-48 exhibited a significantly different bacterial community structure compared to that of non-treated rhizosphere soil. Our results suggest that biocontrol bacteria treatment influences microbial community in tomato rhizosphere, while the chromosomally modified biocontrol bacteria may not pose any specific environmental risk in terms of gene transfer. PMID:27147933

  12. Inoculating plants with the endophytic bacterium Pseudomonas sp. Ph6-gfp to reduce phenanthrene contamination.

    Science.gov (United States)

    Sun, Kai; Liu, Juan; Gao, Yanzheng; Sheng, Yuehui; Kang, Fuxing; Waigi, Michael Gatheru

    2015-12-01

    Plant organic contamination poses a serious threat to the safety of agricultural products and human health worldwide, and the association of endophytic bacteria with host plants may decrease organic pollutants in planta. In this study, we firstly determined the growth response and biofilm formation of endophytic Pseudomonas sp. Ph6-gfp, and then systematically evaluated the performance of different plant colonization methods (seed soaking (SS), root soaking (RS), leaf painting (LP)) for circumventing the risk of plant phenanthrene (PHE) contamination. After inoculation for 48 h, strain Ph6-gfp grew efficiently with PHE, oxalic acid, or malic acid as the sole sources of carbon and energy. Moreover, strain Ph6-gfp could form robust biofilms in LB medium. In greenhouse hydroponic experiments, strain Ph6-gfp could actively colonize inoculated plants internally, and plants colonized with Ph6-gfp showed a higher capacity for PHE removal. Compared with the Ph6-gfp-free treatment, the accumulations of PHE in Ph6-gfp-colonized plants via SS, RS, and LP were 20.1, 33.1, and 7.1 %, respectively, lower. Our results indicate that inoculating plants with Ph6-gfp could lower the risk of plant PHE contamination. RS was most efficient for improving PHE removal in whole plant bodies by increasing the cell numbers of Ph6-gfp in plant roots. The findings in this study provide an optimized method to strain Ph6-gfp reduce plant PAH residues, which may be applied to agricultural production in PAH-contaminated soil. PMID:26263885

  13. Mercury Removal From Petroleum Based Industries Wastewater By P. Putida

    OpenAIRE

    A. A. M. Azoddein; R. M. Yunus; N. M. Sulaiman; A. B. Bustary; F. A. Azli

    2015-01-01

    ABSTRACT Mercury pollution is one of a primary environmental issue and public health problem. The purpose of this research is to remove the mercury using pure culture Pseudomonas putida ATCC 49128 at optimum growth parameters such as technique of culture acclimatization time and speed of incubator speed. In this study the optimum growth parameters ofP. putida were obtained to achieve the maximum of mercury removal. Thus a field study were carried out at two different location based on petrole...

  14. Novel Essential Role of Ethanol Oxidation Genes at Low Temperature Revealed by Transcriptome Analysis in the Antarctic Bacterium Pseudomonas extremaustralis.

    Science.gov (United States)

    Tribelli, Paula M; Solar Venero, Esmeralda C; Ricardi, Martiniano M; Gómez-Lozano, Maria; Raiger Iustman, Laura J; Molin, Søren; López, Nancy I

    2015-01-01

    Temperature is one of the most important factors for bacterial growth and development. Cold environments are widely distributed on earth, and psychrotolerant and psychrophilic microorganisms have developed different adaptation strategies to cope with the stress derived from low temperatures. Pseudomonas extremaustralis is an Antarctic bacterium able to grow under low temperatures and to produce high amounts of polyhydroxyalkanoates (PHAs). In this work, we analyzed the genome-wide transcriptome by RNA deep-sequencing technology of early exponential cultures of P. extremaustralis growing in LB (Luria Broth) supplemented with sodium octanoate to favor PHA accumulation at 8°C and 30°C. We found that genes involved in primary metabolism, including tricarboxylic acid cycle (TCA) related genes, as well as cytochromes and amino acid metabolism coding genes, were repressed at low temperature. Among up-regulated genes, those coding for transcriptional regulatory and signal transduction proteins were over-represented at cold conditions. Remarkably, we found that genes involved in ethanol oxidation, exaA, exaB and exaC, encoding a pyrroloquinoline quinone (PQQ)-dependent ethanol dehydrogenase, the cytochrome c550 and an aldehyde dehydrogenase respectively, were up-regulated. Along with RNA-seq experiments, analysis of mutant strains for pqqB (PQQ biosynthesis protein B) and exaA were carried out. We found that the exaA and pqqB genes are essential for growth under low temperature in LB supplemented with sodium octanoate. Additionally, p-rosaniline assay measurements showed the presence of alcohol dehydrogenase activity at both 8°C and 30°C, while the activity was abolished in a pqqB mutant strain. These results together with the detection of ethanol by gas chromatography in P. extremaustralis cultures grown at 8°C support the conclusion that this pathway is important under cold conditions. The obtained results have led to the identification of novel components involved

  15. Novel Essential Role of Ethanol Oxidation Genes at Low Temperature Revealed by Transcriptome Analysis in the Antarctic Bacterium Pseudomonas extremaustralis

    Science.gov (United States)

    Tribelli, Paula M.; Solar Venero, Esmeralda C.; Ricardi, Martiniano M.; Gómez-Lozano, Maria; Raiger Iustman, Laura J.; Molin, Søren; López, Nancy I.

    2015-01-01

    Temperature is one of the most important factors for bacterial growth and development. Cold environments are widely distributed on earth, and psychrotolerant and psychrophilic microorganisms have developed different adaptation strategies to cope with the stress derived from low temperatures. Pseudomonas extremaustralis is an Antarctic bacterium able to grow under low temperatures and to produce high amounts of polyhydroxyalkanoates (PHAs). In this work, we analyzed the genome-wide transcriptome by RNA deep-sequencing technology of early exponential cultures of P. extremaustralis growing in LB (Luria Broth) supplemented with sodium octanoate to favor PHA accumulation at 8°C and 30°C. We found that genes involved in primary metabolism, including tricarboxylic acid cycle (TCA) related genes, as well as cytochromes and amino acid metabolism coding genes, were repressed at low temperature. Among up-regulated genes, those coding for transcriptional regulatory and signal transduction proteins were over-represented at cold conditions. Remarkably, we found that genes involved in ethanol oxidation, exaA, exaB and exaC, encoding a pyrroloquinoline quinone (PQQ)-dependent ethanol dehydrogenase, the cytochrome c550 and an aldehyde dehydrogenase respectively, were up-regulated. Along with RNA-seq experiments, analysis of mutant strains for pqqB (PQQ biosynthesis protein B) and exaA were carried out. We found that the exaA and pqqB genes are essential for growth under low temperature in LB supplemented with sodium octanoate. Additionally, p-rosaniline assay measurements showed the presence of alcohol dehydrogenase activity at both 8°C and 30°C, while the activity was abolished in a pqqB mutant strain. These results together with the detection of ethanol by gas chromatography in P. extremaustralis cultures grown at 8°C support the conclusion that this pathway is important under cold conditions. The obtained results have led to the identification of novel components involved

  16. Antiadhesive activity of the biosurfactant pseudofactin II secreted by the Arctic bacterium Pseudomonas fluorescens BD5

    Directory of Open Access Journals (Sweden)

    Janek Tomasz

    2012-02-01

    Full Text Available Abstract Background Pseudofactin II is a recently identified biosurfactant secreted by Pseudomonas fluorescens BD5, the strain obtained from freshwater from the Arctic Archipelago of Svalbard. Pseudofactin II is a novel compound identified as cyclic lipopeptide with a palmitic acid connected to the terminal amino group of eighth amino acid in peptide moiety. The C-terminal carboxylic group of the last amino acid forms a lactone with the hydroxyl of Thr3. Adhesion is the first stage of biofilm formation and the best moment for the action of antiadhesive and anti-biofilm compounds. Adsorption of biosurfactants to a surface e.g. glass, polystyrene, silicone modifies its hydrophobicity, interfering with the microbial adhesion and desorption processes. In this study the role and applications of pseudofactin II as a antiadhesive compound has been investigated from medicinal and therapeutic perspectives. Results Pseudofactin II lowered the adhesion to three types of surfaces (glass, polystyrene and silicone of bacterial strains of five species: Escherichia coli, Enterococcus faecalis, Enterococcus hirae, Staphylococcus epidermidis, Proteus mirabilis and two Candida albicans strains. Pretreatment of a polystyrene surface with 0.5 mg/ml pseudofactin II inhibited bacterial adhesion by 36-90% and that of C. albicans by 92-99%. The same concentration of pseudofactin II dislodged 26-70% of preexisting biofilms grown on previously untreated surfaces. Pseudofactin II also caused a marked inhibition of the initial adhesion of E. faecalis, E. coli, E. hirae and C. albicans strains to silicone urethral catheters. The highest concentration tested (0.5 mg/ml caused a total growth inhibition of S. epidermidis, partial (18-37% inhibition of other bacteria and 8-9% inhibition of C. albicans growth. Conclusion Pseudofactin II showed antiadhesive activity against several pathogenic microorganisms which are potential biofilm formers on catheters, implants and internal

  17. The biocontrol endophytic bacterium Pseudomonas fluorescens PICF7 induces systemic defense responses in aerial tissues upon colonization of olive roots

    Directory of Open Access Journals (Sweden)

    Carmen eGómez-Lama Cabanás

    2014-09-01

    Full Text Available Pseudomonas fluorescens PICF7, a native olive root endophyte and effective biocontrol agent (BCA against Verticillium wilt of olive, is able to trigger a broad range of defense responses in root tissues of this woody plant. In order to elucidate whether strain PICF7 also induces systemic defense responses in above-ground organs, aerial tissues of olive plants grown under non-gnotobiotic conditions were collected at different time points after root bacterization with this endophytic BCA. A suppression subtractive hybridization (SSH cDNA library, enriched in up-regulated genes, was generated. This strategy enabled the identification of 376 ESTs (99 contigs and 277 singlets, many of them related to response to different stresses. Five ESTs, involved in defense responses, were selected to carry out time-course quantitative real-time PCR (qRT-PCR experiments aiming to: (i validate the induction of these genes, and (ii shed light on their expression pattern along time (from 1 to 15 days. Induction of olive genes potentially coding for lypoxigenase 2, catalase, 1-aminocyclopropane-1-carboxylate oxidase and phenylananine ammonia-lyase was thus confirmed at some time points. Computational analysis also revealed that different transcription factors were up-regulated in olive aerial tissues (i.e. jerf, bHLH, WRKYs, as previously reported for roots. Results confirmed that root colonization by this endophytic bacterium does not only trigger defense responses in this organ but also mount a wide array of systemic defense responses in distant tissues (stems, leaves. This sheds light on how olive plants respond to the ‘non-hostile’ colonization by a bacterial endophyte and how induced defense response can contribute to the biocontrol activity of strain PICF7.

  18. Negative Cross-Communication among Wheat Rhizosphere Bacteria: Effect on Antibiotic Production by the Biological Control Bacterium Pseudomonas aureofaciens 30-84

    OpenAIRE

    Morello, J. E.; Pierson, E.A.; Pierson, L S

    2004-01-01

    Phenazine antibiotic production in the biological control bacterium Pseudomonas aureofaciens 30-84 is regulated in part via the PhzR/PhzI N-acyl homoserine lactone (AHL) system. Previous work showed that a subpopulation of the wheat rhizosphere community positively affected phenazine gene expression in strain 30-84 via AHL signals (E. A. Pierson, D. W. Wood, J. A. Cannon, F. M. Blachere, and L. S. Pierson III, Mol. Plant-Microbe Interact. 11:1078-1084, 1998). In the present work, a second sub...

  19. Draft Genome Sequence of Pseudomonas sp. Strain BMS12, a Plant Growth-Promoting and Protease-Producing Bacterium, Isolated from the Rhizosphere Sediment of Phragmites karka of Chilika Lake, India.

    Science.gov (United States)

    Mishra, Samir R; Panda, Ananta Narayan; Ray, Lopamudra; Sahu, Neha; Mishra, Gayatri; Jadhao, Sudhir; Suar, Mrutyunjay; Adhya, Tapan Kumar; Rastogi, Gurdeep; Pattnaik, Ajit Kumar; Raina, Vishakha

    2016-01-01

    We report the 4.51 Mb draft genome of Pseudomonas sp. strain BMS12, a Gram-negative bacterium in the class of Gammaproteobacteria, isolated from the rhizospheric sediment of Phragmites karka, an invasive weed in Chilika Lake, Odisha, India. The Pseudomonas sp. strain BMS12 is capable of producing proteases and is also an efficient plant growth promoter that can be useful for various phytoremedial and industrial applications. PMID:27365340

  20. Draft Genome Sequence of Pseudomonas sp. Strain BMS12, a Plant Growth-Promoting and Protease-Producing Bacterium, Isolated from the Rhizosphere Sediment of Phragmites karka of Chilika Lake, India

    Science.gov (United States)

    Mishra, Samir R.; Panda, Ananta Narayan; Ray, Lopamudra; Sahu, Neha; Mishra, Gayatri; Jadhao, Sudhir; Suar, Mrutyunjay; Adhya, Tapan Kumar; Rastogi, Gurdeep; Pattnaik, Ajit Kumar

    2016-01-01

    We report the 4.51 Mb draft genome of Pseudomonas sp. strain BMS12, a Gram-negative bacterium in the class of Gammaproteobacteria, isolated from the rhizospheric sediment of Phragmites karka, an invasive weed in Chilika Lake, Odisha, India. The Pseudomonas sp. strain BMS12 is capable of producing proteases and is also an efficient plant growth promoter that can be useful for various phytoremedial and industrial applications. PMID:27365340

  1. Evaluation of MicroScan Autoscan for Identification of Pseudomonas aeruginosa Isolates from Cystic Fibrosis Patients

    OpenAIRE

    Saiman, Lisa; Burns, Jane L.; Larone, Davise; Chen, Yunhua; Garber, Elizabeth; Whittier, Susan

    2003-01-01

    Accurate identification of gram-negative bacilli from cystic fibrosis (CF) patients is essential. Only 57% (108 of 189) of nonmucoid strains and 40% (24 of 60) of mucoid strains were definitively identified as Pseudomonas aeruginosa with MicroScan Autoscan. Most common misidentifications were Pseudomonas fluorescens-Pseudomonas putida (i.e., the strain was either P. fluorescens or P. putida, but the system did not make the distinction and yielded the result P. fluorescens/putida) and Alcalige...

  2. Sequential interactions of silver-silica nanocomposite (Ag-SiO2 NC) with cell wall, metabolism and genetic stability of Pseudomonas aeruginosa, a multiple antibiotic-resistant bacterium

    Digital Repository Service at National Institute of Oceanography (India)

    Anas, A.; Jiya, J.; Rameez, M.J.; Anand, P.B.; Anantharaman, M.R.; Nair, S.

    The study was carried out to understand the effect of silver–silica nanocomposite (Ag-SiO sub(2)NC) on the cell wall integrity, metabolism and genetic stability of Pseudomonas aeruginosa, a multiple drug-resistant bacterium. Bacterial sensitivity...

  3. Mercury Removal From Petroleum Based Industries Wastewater By P. Putida

    Directory of Open Access Journals (Sweden)

    A. A. M. Azoddein

    2015-06-01

    Full Text Available ABSTRACT Mercury pollution is one of a primary environmental issue and public health problem. The purpose of this research is to remove the mercury using pure culture Pseudomonas putida ATCC 49128 at optimum growth parameters such as technique of culture acclimatization time and speed of incubator speed. In this study the optimum growth parameters ofP. putida were obtained to achieve the maximum of mercury removal. Thus a field study were carried out at two different location based on petroleum industrial plants in Peninsular Malaysia. Processes involved in this research which is P. putida behavior in rehydrating free-dried growing method growth parameters and optimum operating conditions. Analysis that carried out are turbidity total dissolved solid and suspended solid where related to growth of P. putida. Efficiency of mercury removal from actual petroleum based industries plant 1 P1 wastewater with the presence of 1000 ppb Hg increased from 84 after 4 hours to 90.5 after 96 hours. For plant 2 the sample with presence P. putida and nutrient broth had the highest of mercury removal which is 97.27. This results show by using P. putida is efficient for mercury removal from actual petroleum.

  4. Effect of primary substrate on co-metabolism of bezafibrate by Pseudomonas putida%初级基质对降解菌Pseudomonas putida共代谢苯扎贝特的影响

    Institute of Scientific and Technical Information of China (English)

    徐冰洁; 薛罡; 高品; 刘亚男; 曾超; 吴凡

    2014-01-01

    通过对3,5-二硝基水杨酸(DNS)法测定还原糖含量各影响因素的筛选,优化确定了显色时间8 min,稳定时间10 min,最佳波长490 nm下进行吸光度测定的检测方法;分析分别以葡萄糖和麦芽糖作为外加碳源时,降解菌Pseudo-monas putida B-31的生长情况和共代谢降解典型药物苯扎贝特(BZF)的过程.结果表明,降解菌只有在外加碳源的条件下才可正常生长,而且其在葡萄糖环境中生长得更好;拟合得到的葡萄糖、麦芽糖和BZF代谢动力学结果显示,葡萄糖对BZF去除的促进作用更为明显,同时从葡萄糖培养基中降解菌所提取的酶比活力要高于麦芽糖培养基,分析原因可能是葡萄糖所诱导的降解菌关键酶活力更强,而且还可能会产生不同的蛋白质点位.

  5. Molecular Stress Responses to Nano-Sized Zero-Valent Iron (nZVI) Particles in the Soil Bacterium Pseudomonas stutzeri

    Science.gov (United States)

    Saccà, Maria Ludovica; Fajardo, Carmen; Martinez-Gomariz, Montserrat; Costa, Gonzalo; Nande, Mar; Martin, Margarita

    2014-01-01

    Nanotoxicological studies were performed in vitro using the common soil bacterium Pseudomonas stutzeri to assess the potentially toxic impact of commercial nano-sized zero-valent iron (nZVI) particles, which are currently used for environmental remediation projects. The phenotypic response of P. stutzeri to nZVI toxicity includes an initial insult to the cell wall, as evidenced by TEM micrographs. Transcriptional analyses using genes of particular relevance in cellular activity revealed that no significant changes occurred among the relative expression ratios of narG, nirS, pykA or gyrA following nZVI exposure; however, a significant increase in katB expression was indicative of nZVI-induced oxidative stress in P. stutzeri. A proteomic approach identified two major defence mechanisms that occurred in response to nZVI exposure: a downregulation of membrane proteins and an upregulation of proteins involved in reducing intracellular oxidative stress. These biomarkers served as early indicators of nZVI response in this soil bacterium, and may provide relevant information for environmental hazard assessment. PMID:24586957

  6. Chronic ecotoxic effects to Pseudomonas putida and Vibrio fischeri, and cytostatic and genotoxic effects to the hepatoma cell line (HepG2) of ofloxacin photo(cata)lytically treated solutions

    Energy Technology Data Exchange (ETDEWEB)

    Vasquez, M.I. [University of Cyprus, Department of Civil and Environmental Engineering, University of Cyprus, 75 Kallipoleos Street, 1678 Nicosia (Cyprus); Nireas International Water Research Center, University of Cyprus (Cyprus); Garcia-Käufer, M. [University Medical Centre Freiburg, Department of Environmental Health Sciences, 115 B, Breisacher Straße, 79106 Freiburg (Germany); Hapeshi, E. [University of Cyprus, Department of Civil and Environmental Engineering, University of Cyprus, 75 Kallipoleos Street, 1678 Nicosia (Cyprus); Nireas International Water Research Center, University of Cyprus (Cyprus); Menz, J. [Institute of Sustainable and Environmental Chemistry, Leuphana University Lüneburg, Scharnhorststraße 1/C13, 21335 Lüneburg (Germany); Kostarelos, K.; Fatta-Kassinos, D. [University of Cyprus, Department of Civil and Environmental Engineering, University of Cyprus, 75 Kallipoleos Street, 1678 Nicosia (Cyprus); Nireas International Water Research Center, University of Cyprus (Cyprus); Kümmerer, K., E-mail: Klaus.Kuemmerer@uni.leuphana.de [Institute of Sustainable and Environmental Chemistry, Leuphana University Lüneburg, Scharnhorststraße 1/C13, 21335 Lüneburg (Germany)

    2013-04-15

    Ofloxacin (OFL), a broad-spectrum and widespread-used photolabile fluoroquinolone, is frequently found in treated wastewaters, aquatic and terrestrial ecosystems leading to increasing concern during the past decades regarding its effects to the environment and human health. The elimination of OFL and other xenobiotics by the application of advanced oxidation processes using photolytic (PL) and photocatalytic (PC) treatments seems promising. However, an integrated assessment scheme is needed, in which, not only the removal of the parent compound, but also the effects of the photo-transformation products (PTPs) are investigated. For this purpose, in the present study, a chronic ecotoxic assessment using representative bacteria of marine and terrestrial ecosystems and a cytostatic and genotoxic evaluation using hepatoma cell line were performed. PL and PC treatments of OFL were applied using UV radiation. The photo-transformation of OFL during the treatments was monitored by DOC measurements and UPLC–MS/MS analysis. The chronic ecotoxicity of OFL and treated samples was evaluated using Pseudomonas putida and Vibrio fischeri; whereas the cytostasis and genotoxicity were estimated by the cytokinesis-block micronucleus assay (CBMN). The main results suggest that photo-transformation of OFL took place during these treatments since the concentration of OFL decreased when the irradiation time increased, as quantified by UPLC–MS/MS analysis, and this was not coupled with an analogous DOC removal. Furthermore, nine compounds were identified as probable PTPs formed through piperazinyl dealkylation and decarboxylation. The ecotoxicity of treated solutions to the bacteria studied decreased while the cytostasis to the hepatoma cell line remained at low levels during both treatments. However, the genotoxicity to the hepatoma cell line demonstrated a different pattern in which treated samples induced a greater number of MNi for the 4–16 min of irradiation (p < 0.05) during

  7. Chronic ecotoxic effects to Pseudomonas putida and Vibrio fischeri, and cytostatic and genotoxic effects to the hepatoma cell line (HepG2) of ofloxacin photo(cata)lytically treated solutions

    International Nuclear Information System (INIS)

    Ofloxacin (OFL), a broad-spectrum and widespread-used photolabile fluoroquinolone, is frequently found in treated wastewaters, aquatic and terrestrial ecosystems leading to increasing concern during the past decades regarding its effects to the environment and human health. The elimination of OFL and other xenobiotics by the application of advanced oxidation processes using photolytic (PL) and photocatalytic (PC) treatments seems promising. However, an integrated assessment scheme is needed, in which, not only the removal of the parent compound, but also the effects of the photo-transformation products (PTPs) are investigated. For this purpose, in the present study, a chronic ecotoxic assessment using representative bacteria of marine and terrestrial ecosystems and a cytostatic and genotoxic evaluation using hepatoma cell line were performed. PL and PC treatments of OFL were applied using UV radiation. The photo-transformation of OFL during the treatments was monitored by DOC measurements and UPLC–MS/MS analysis. The chronic ecotoxicity of OFL and treated samples was evaluated using Pseudomonas putida and Vibrio fischeri; whereas the cytostasis and genotoxicity were estimated by the cytokinesis-block micronucleus assay (CBMN). The main results suggest that photo-transformation of OFL took place during these treatments since the concentration of OFL decreased when the irradiation time increased, as quantified by UPLC–MS/MS analysis, and this was not coupled with an analogous DOC removal. Furthermore, nine compounds were identified as probable PTPs formed through piperazinyl dealkylation and decarboxylation. The ecotoxicity of treated solutions to the bacteria studied decreased while the cytostasis to the hepatoma cell line remained at low levels during both treatments. However, the genotoxicity to the hepatoma cell line demonstrated a different pattern in which treated samples induced a greater number of MNi for the 4–16 min of irradiation (p < 0.05) during

  8. Microcalorimetric and potentiometric titration studies on the adsorption of copper by P. putida and B. thuringiensis and their composites with minerals

    International Nuclear Information System (INIS)

    In order to have a better understanding of the interactions of heavy metals with bacteria and minerals in soil and associated environments, isothermal titration calorimetry (ITC), potentiometric titration and equilibrium sorption experiments were conducted to investigate the adsorption behavior of Cu(II) by Bacillus thuringiensis, Pseudomonas putida and their composites with minerals. The interaction of montmorillonite with bacteria increased the reactive sites and resulted in greater adsorption for Cu(II) on their composites, while decreased adsorption sites and capacities for Cu(II) were observed on goethite-bacteria composites. A gram-positive bacterium B. thuringiensis played a more important role than a gram-negative bacterium P. putida in determining the properties of the bacteria-minerals interfaces. The enthalpy changes (ΔHads) from endothermic (6.14 kJ mol-1) to slightly exothermic (-0.78 kJ mol-1) suggested that Cu(II) is complexed with the anionic oxygen ligands on the surface of bacteria-mineral composites. Large entropies (32.96-58.89 J mol-1 K-1) of Cu(II) adsorption onto bacteria-mineral composites demonstrated the formation of inner-sphere complexes in the presence of bacteria. The thermodynamic data implied that Cu(II) mainly bound to the carboxyl and phosphoryl groups as inner-sphere complexes on bacteria and mineral-bacteria composites.

  9. Microcalorimetric and potentiometric titration studies on the adsorption of copper by P. putida and B. thuringiensis and their composites with minerals

    Energy Technology Data Exchange (ETDEWEB)

    Fang Linchuan [State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070 (China); Key Laboratory of Subtropical Agriculture and Environment, Ministry of Agriculture, College of Resources and Environment, Huazhong Agricultural University, Wuhan 430070 (China); Cai Peng; Li Pengxiang; Wu Huayong; Liang Wei; Rong Xingmin [Key Laboratory of Subtropical Agriculture and Environment, Ministry of Agriculture, College of Resources and Environment, Huazhong Agricultural University, Wuhan 430070 (China); Chen Wenli [State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070 (China); Huang Qiaoyun, E-mail: qyhuang@mail.hzau.edu.cn [State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070 (China); Key Laboratory of Subtropical Agriculture and Environment, Ministry of Agriculture, College of Resources and Environment, Huazhong Agricultural University, Wuhan 430070 (China)

    2010-09-15

    In order to have a better understanding of the interactions of heavy metals with bacteria and minerals in soil and associated environments, isothermal titration calorimetry (ITC), potentiometric titration and equilibrium sorption experiments were conducted to investigate the adsorption behavior of Cu(II) by Bacillus thuringiensis, Pseudomonas putida and their composites with minerals. The interaction of montmorillonite with bacteria increased the reactive sites and resulted in greater adsorption for Cu(II) on their composites, while decreased adsorption sites and capacities for Cu(II) were observed on goethite-bacteria composites. A gram-positive bacterium B. thuringiensis played a more important role than a gram-negative bacterium P. putida in determining the properties of the bacteria-minerals interfaces. The enthalpy changes ({Delta}H{sub ads}) from endothermic (6.14 kJ mol{sup -1}) to slightly exothermic (-0.78 kJ mol{sup -1}) suggested that Cu(II) is complexed with the anionic oxygen ligands on the surface of bacteria-mineral composites. Large entropies (32.96-58.89 J mol{sup -1} K{sup -1}) of Cu(II) adsorption onto bacteria-mineral composites demonstrated the formation of inner-sphere complexes in the presence of bacteria. The thermodynamic data implied that Cu(II) mainly bound to the carboxyl and phosphoryl groups as inner-sphere complexes on bacteria and mineral-bacteria composites.

  10. Comparative genome analysis of Pseudomonas knackmussii B13, the first bacterium known to degrade chloroaromatic compounds.

    Science.gov (United States)

    Miyazaki, Ryo; Bertelli, Claire; Benaglio, Paola; Canton, Jonas; De Coi, Nicoló; Gharib, Walid H; Gjoksi, Bebeka; Goesmann, Alexander; Greub, Gilbert; Harshman, Keith; Linke, Burkhard; Mikulic, Josip; Mueller, Linda; Nicolas, Damien; Robinson-Rechavi, Marc; Rivolta, Carlo; Roggo, Clémence; Roy, Shantanu; Sentchilo, Vladimir; Siebenthal, Alexandra Von; Falquet, Laurent; van der Meer, Jan Roelof

    2015-01-01

    Pseudomonas knackmussii B13 was the first strain to be isolated in 1974 that could degrade chlorinated aromatic hydrocarbons. This discovery was the prologue for subsequent characterization of numerous bacterial metabolic pathways, for genetic and biochemical studies, and which spurred ideas for pollutant bioremediation. In this study, we determined the complete genome sequence of B13 using next generation sequencing technologies and optical mapping. Genome annotation indicated that B13 has a variety of metabolic pathways for degrading monoaromatic hydrocarbons including chlorobenzoate, aminophenol, anthranilate and hydroxyquinol, but not polyaromatic compounds. Comparative genome analysis revealed that B13 is closest to Pseudomonas denitrificans and Pseudomonas aeruginosa. The B13 genome contains at least eight genomic islands [prophages and integrative conjugative elements (ICEs)], which were absent in closely related pseudomonads. We confirm that two ICEs are identical copies of the 103 kb self-transmissible element ICEclc that carries the genes for chlorocatechol metabolism. Comparison of ICEclc showed that it is composed of a variable and a 'core' region, which is very conserved among proteobacterial genomes, suggesting a widely distributed family of so far uncharacterized ICE. Resequencing of two spontaneous B13 mutants revealed a number of single nucleotide substitutions, as well as excision of a large 220 kb region and a prophage that drastically change the host metabolic capacity and survivability. PMID:24803113

  11. Homologous functional expression of cryptic phaG from Pseudomonas oleovorans establishes the transacylase-mediated polyhydroxyalkanoate biosynthetic pathway.

    Science.gov (United States)

    Hoffmann, N; Steinbüchel, A; Rehm, B H

    2000-11-01

    Various pseudomonads are capable of the synthesis of polyhydroxyalkanoate (PHA), composed of medium chain length (MCL) 3-hydroxy fatty acids (C6-C14), when grown on simple carbon sources such as, for example, gluconate or acetate. In Pseudomonas putida, the fatty acid de novo synthesis and PHA synthesis are linked by the transacylase PhaG. Southern hybridization experiments with digoxigenin-labeled phaG(Pp) from P. putida and genomic DNA from various pseudomonads indicate that phaG homologues are present in various other pseudomonads. Although P. oleovorans does not accumulate PHA(MCL) from non-related carbon sources, its genomic DNA reveals a strong hybridization signal. We employed PCR to amplify this phaG homologue. The respective PCR product comprising the coding region of phaG(Po) was cloned into pBBR1MCS-2, resulting in plasmid pBHR84. DNA sequencing revealed that putative PhaG(Po) from P. oleovorans exhibited about 95% amino acid sequence identity to PhaG(Pp) from P. putida. Reverse transcriptase-PCR analysis demonstrated that phaG(Po) was not transcribed even tinder inducing conditions, i.e. in the presence of gluconate as carbon source, whereas induction of phaG(Pp) transcription was obtained in P. putida. When octanoate was used as sole carbon source, only low levels of phaG mRNA were detected in P. putida. Plasmid pBHR84 complemented the phaG-negative mutant PhaG(N)-21 from P. putida. Interestingly, reintroduction of phaG(Po) under lac promoter control into the natural host P. oleovorans established PHA(MCL) synthesis from non-related carbon sources in this bacterium. These data indicated that phaG(Po) in P. oleovorans is not functionally expressed and does not exert its original function. PMID:11131392

  12. 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

    OpenAIRE

    Dimkpa, Christian O.; 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...

  13. Genetic responses induced in olive roots upon colonization by the biocontrol endophytic bacterium Pseudomonas fluorescens PICF7.

    Directory of Open Access Journals (Sweden)

    Elisabetta Schilirò

    Full Text Available 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.

  14. Involvement of quorum sensing genes in biofilm development and degradation of polycyclic aromatic hydrocarbons by a marine bacterium Pseudomonas aeruginosa N6P6.

    Science.gov (United States)

    Mangwani, Neelam; Kumari, Supriya; Das, Surajit

    2015-12-01

    Biofilm-forming and acyl homoserine lactone (AHL) synthase-positive Pseudomonas aeruginosa N6P6 was isolated from seawater after selective enrichment with two polycyclic aromatic hydrocarbons (PAHs), viz. phenanthrene and pyrene. AHL synthesis was detected qualitatively using bioreporter strains. This marine bacterium putatively synthesized N-(3-oxododecanoyl)-L-homoserine lactone and N-butyryl-L-homoserine lactone, which were identified by TLC, GC-MS, and HPLC. Two quorum sensing (QS) genes coding for AHL synthase, i.e., lasI and rhlI, were identified in the bacterium. lasI and rhlI gene expression was studied during biofilm mode of growth at different phases using quantitative real-time PCR (qRT-PCR). The expression of lasI increased with increase in biofilm growth. In contrast, the expression of rhlI decreased during log phase of biofilm growth. The changes in lasI/rhlI expression level had significant effects (Pbiofilm architecture and subsequent PAH degradation rate. Degradation of phenanthrene and pyrene by P. aeruginosa N6P6 was affected by biofilm growth and lasI expression. The respective phenanthrene degradation for 15, 24, 48, and 72 h old biofilm after 7 days was 21.5, 54.2, 85.6, and 85.7%. However, the corresponding pyrene degradation was 15, 18.28, 47.56, and 46.48%, respectively, after 7 days. A significant positive correlation (Pbiofilm formation, and pyocyanin production reduced significantly which confirmed the pivotal role of QS in biodegradation of PAHs. The findings suggest that AHLs play a pivotal role during biofilm development and subsequent bioremediation of PAHs. PMID:26245683

  15. Cloning and heterologous overexpression of three gap genes encoding different glyceraldehyde-3-phosphate dehydrogenases from the plant pathogenic bacterium Pseudomonas syringae pv. tomato strain DC3000.

    Science.gov (United States)

    Elkhalfi, Bouchra; Araya-Garay, José Miguel; Rodríguez-Castro, Jorge; Rey-Méndez, Manuel; Soukri, Abdelaziz; Serrano Delgado, Aurelio

    2013-06-01

    The gammaproteobacterium Pseudomonas syringae pv. tomato DC3000 is the causal agent of bacterial speck, a common disease of tomato. The mode of infection of this pathogen is not well understood, but according to molecular biological, genomic and proteomic data it produces a number of proteins that may promote infection and draw nutrients from the plant. Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is a major enzyme of carbon metabolism that was reported to be a surface antigen and virulence factor in other pathogenic microorganisms, but its possible role in the infection process of P. syringae has so far not been studied. Whole-genome sequence analyses revealed the occurrence in this phytopathogenic bacterium of three paralogous gap genes encoding distinct GAPDHs, namely two class I enzymes having different molecular mass subunits and one class III bifunctional D-erythrose-4-phosphate dehydrogenase/GAPDH enzyme. By using genome bioinformatics data, as well as alignments of both DNA and deduced protein sequences, the three gap genes of P. syringae were one-step cloned with a His-Tag in pET21a vector using a PCR-based strategy, and its expression optimized in Escherichia coli BL21 to achieve high yield of the heterologous proteins. In accordance with their distinct molecular phylogenies, these bacterial gap genes encode functional GAPDHs of diverse molecular masses and nicotinamide-coenzyme specificities, suggesting specific metabolic and/or cellular roles. PMID:23507306

  16. Determination of the structure of the O-antigen and the lipid A from the entomopathogenic bacterium Pseudomonas entomophila lipopolysaccharide along with its immunological properties.

    Science.gov (United States)

    Speciale, Immacolata; Paciello, Ida; Fazio, Luigi Lembo; Sturiale, Luisa; Palmigiano, Angelo; Lanzetta, Rosa; Parrilli, Michelangelo; Garozzo, Domenico; Lemaitre, Bruno; Bernardini, Maria Lina; Molinaro, Antonio; De Castro, Cristina

    2015-08-14

    The structure and the immunology of the lipopolysaccharide (LPS) of Pseudomonas entomophila, an entomopathogenic bacterium isolated from the fruit fly Drosophila melanogaster, was characterized. The O-antigen portion was established and resulted to be built up of a repetitive unit constituted by four monosaccharide residues, all L configured, all deoxy at C-6 and with an acetamido function at C-2: →3)-α-l-FucNAc-(1→4)-α-l-FucNAc-(1→3)-α-l-FucNAc-(1→3)-β-l-QuiNAc-(1→ The structural analysis of lipid A, showed a mixture of different species. The diphosphorylated glucosamine backbone carries six fatty acids consistent with the composition C10:0 3(OH), C12:0 2(OH) and C12:0 3(OH), whereas other species differs by the number of phosphates and/or of fatty acids. The immunology experiments demonstrated that the LPS structure of P. entomophila displayed a low ability to engage the TLR4-mediated signaling correlated to a significant antagonistic activity toward hexa-acylated LPS structures. PMID:25996527

  17. The Sensor Kinase GacS Negatively Regulates Flagellar Formation and Motility in a Biocontrol Bacterium, Pseudomonas chlororaphis O6

    Directory of Open Access Journals (Sweden)

    Ji Soo Kim

    2014-06-01

    Full Text Available The GacS/GacA two component system regulates various traits related to the biocontrol potential of plant-associated pseudomonads. The role of the sensor kinase, GacS, differs between strains in regulation of motility. In this study, we determined how a gacS mutation changed cell morphology and motility in Pseudomonas chlororaphis O6. The gacS mutant cells were elongated in stationary-phase compared to the wild type and the complemented gacS mutant, but cells did not differ in length in logarithmic phase. The gacS mutant had a two-fold increase in the number of flagella compared with the wild type strain; flagella number was restored to that of the wild type in the complemented gacS mutant. The more highly flagellated gacS mutant cells had greater swimming motilities than that of the wild type strain. Enhanced flagella formation in the gacS mutant correlated with increased expression of three genes, fleQ, fliQ and flhF, involved in flagellar formation. Expression of these genes in the complemented gacS mutant was similar to that of the wild type. These findings show that this root-colonizing pseudomonad adjusts flagella formation and cell morphology in stationary-phase using GacS as a major regulator.

  18. [Quorum sensing systems of regulation, synthesis of phenazine antibiotics, and antifungal (corrected) activity in rhizospheric bacterium Pseudomonas chlororaphis 449].

    Science.gov (United States)

    Veselova, M a; Klein, Sh; Bass, I A; Lipasova, V A; Metlitskaia, A Z; Ovadis, M I; Chernin, L S; Khmel', I A

    2008-12-01

    Strain Pseudomonas chlororaphis 449, an antagonist of a broad spectrum of phytopathogenic microorganisms isolated from the maize rhizosphere, was shown to produce three phenazine antibiotics: phenazine-1-carboxylic acid (PCA), 2-hydroxylphenazine-1-carboxylic acid (2-OH-PCA), and 2-hydroxylphenazine (2-OH-PHZ). Two Quorum Sensing (QS) systems of regulation were identified: PhzIR and CsaI/R. Genes phzI and csaI were cloned and sequenced. Cells of strain 449 synthesize at least three types of AHL: N-butanoyl-L-homoserine lactone (C4-AHL), N-hexanoyl-L-homoserine lactone (C6-AHL), and N-(3-oxo-hexanoyl)-L-homoserine lactone (30C6-AHL). Transposon mutagenesis was used to generate mutants of strain 449 deficient in synthesis of phenazines, which carried inactivated phzA and phzB genes of the phenazine operon and gene phzO. Mutations phzA- and phzB-caused a drastic reduction in the antagonistic activity of bacteria toward phytopathogenic fungi. Both mutants lost the ability to protect cucumber and leguminous plants against phytopathogenic fungi Rhizoctonia solani and Sclerotinia sclerotiorum. These results suggest a significant role of phenazines in the antagonistic activity of P. chlororaphis 449. PMID:19178080

  19. Acquisition of Fe from Natural Organic Matter by an Aerobic Pseudomonas Bacterium: Siderophores and Cellular Fe Status

    Science.gov (United States)

    Koehn, K.; Dehner, C.; Dubois, J.; Maurice, P. A.

    2010-12-01

    Aerobic microorganisms have evolved various strategies to acquire nutrient Fe, including release of Fe-chelating siderophores. The potential importance of siderophores in Fe acquisition from natural organic matter (NOM) (reverse osmosis, RO; and XAD-8 samples with naturally associated Fe) was investigated using a wild type strain (WT) of aerobic Pseudomonas mendocina that produces siderophore(s) and an engineered mutant that cannot. Microbial growth under Fe-limited batch conditions was monitored via optical density, and a β-galactosidase biosensor assay was used to quantify cellular Fe status. Both WT and mutant strains acquired Fe from NOM. Fe ‘stress’ in the presence of the RO sample decreased with increasing [Fe] (as determined by different [DOC]s) and was consistently less for the WT. For both WT and mutant, maximum growth in the presence of RO sample increased as: 1 mgC/L (0.2μM Fe) remove metals associated with the RO sample increased Fe stress but did not substantially affect growth. Results demonstrated that: (1) siderophores are useful but not necessary for Fe acquisition from NOM by P. mendocina and (2) NOM may have complex effects on microbial growth, related not just to Fe content but potentially to the presence of other (trace)metals such as Al and/or to effects on biofilm development.

  20. Diversity of small RNAs expressed in Pseudomonas species

    DEFF Research Database (Denmark)

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

    2015-01-01

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

  1. Headspace analysis of volatile metabolites of Pseudomonas aeruginosa and related species by gas chromatography-mass spectrometry.

    OpenAIRE

    Labows, J N; McGinley, K J; Webster, G F; Leyden, J J

    1980-01-01

    Gas chromatographic-mass spectrometric analysis of headspace volatiles was performed on cultures of 11 strains of Pseudomonas aeruginosa and 1 strain each of Pseudomonas cepacia, Pseudomonas putida, Pseudomonas putrefaciens, Pseudomonas fluorescens, and Pseudomonas maltophilia. All strains of Pseudomonas aeruginosa produced a distinctive series of odd-carbon methyl ketones, particularly 2-nonanone and 2-undecanone, and 2-aminoacetophenone. The other strains failed to produce 2-aminoacetopheno...

  2. Complete Genome Sequence of Pseudomonas sp. UK4, a Model Organism for Studies of Functional Amyloids in Pseudomonas

    OpenAIRE

    Dueholm, Morten Simonsen; Danielsen, Heidi Nolsøe; Nielsen, Per Halkjær

    2014-01-01

    Here, we present the complete genome of Pseudomonas sp. UK4. This bacterium was the first Pseudomonas strain shown to produce functional amyloids, and it represents a model organism for studies of functional amyloids in Pseudomonas (Fap).

  3. Engineering a predatory bacterium as a proficient killer agent for intracellular bio-products recovery: The case of the polyhydroxyalkanoates

    Science.gov (United States)

    Martínez, Virginia; Herencias, Cristina; Jurkevitch, Edouard; Prieto, M. Auxiliadora

    2016-01-01

    This work examines the potential of the predatory bacterium Bdellovibrio bacteriovorus HD100, an obligate predator of other Gram-negative bacteria, as an external cell-lytic agent for recovering valuable intracellular bio-products produced by prey cultures. The bio-product targets to be recovered were polyhydroxyalkanoates (PHAs) produced naturally by Pseudomonas putida and Cupriavidus necator, or by recombinant Escherichia coli strains. B. bacteriovorus with a mutated PHA depolymerase gene to prevent the unwanted breakdown of the bio-product allowed the recovery of up to 80% of that accumulated by the prey bacteria, even at high biomass concentrations. This innovative downstream process highlights how B. bacteriovorus can be used as a novel, biological lytic agent for the inexpensive, industrial scale recovery of intracellular products from different Gram-negative prey cultures. PMID:27087466

  4. Comparative in vitro activities of newer quinolones against Pseudomonas species and Xanthomonas maltophilia isolated from patients with cancer.

    OpenAIRE

    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 q...

  5. Conservation of the multidrug resistance efflux gene oprM in Pseudomonas aeruginosa.

    OpenAIRE

    BIANCO, N.; Neshat, S; Poole, K

    1997-01-01

    An intragenic probe derived from the multidrug resistance gene oprM hybridized with genomic DNA from all 20 serotypes of Pseudomonas aeruginosa and from all 34 environmental and clinical isolates tested, indicating that the MexA-MexB-OprM multidrug efflux system is highly conserved in this organism. The oprM probe also hybridized with genomic DNA from Pseudomonas aureofaciens, Pseudomonas chlororaphis, Pseudomonas syringae, Burkholderia pseudomallei, and Pseudomonas putida, suggesting that ef...

  6. RECUPERACIÓN DE POLI-b-HIDROXIHEXANOATO- CO-OCTANOATO SINTETIZADO POR Pseudomonas putida MEDIANTE EL USO DE DISPERSIONES H I P O C LO R I TO - C LO RO F O R M O

    Directory of Open Access Journals (Sweden)

    A. Espinosa-Hernández

    2006-06-01

    Full Text Available Se estandarizó una técnica de recuperación de poli-3-hidroxihexanoato-co-hidroxioctanoato a partir de P. putida. El método emplea dispersiones de hipoclorito de sodio-cloroformo para la digestión delmaterial celular y solubilización del polímero, respectivamente. Se evaluó el efecto de la concentración de hipoclorito, la temperatura y el tiempo sobre el porcentaje de recuperación, pureza, peso molecular y temperatura de fusión. Las mejores condiciones para recuperar este polímero fueron: hipoclorito al 5.25% (p/v a 60°C durante 1 hora. Empleando estas condiciones fue posible mantener el peso molecularpor encima del 87% con respecto al obtenido mediante extracción con cloroformo. La temperatura de fusión del polímero fue 57.7°C y 56.4°C para dos muestras al azar. La pureza del material recuperado esde 96%.

  7. Genes expressed by the biological control bacterium Pseudomonas protegens Pf-5 on seed surfaces under the control of the global regulators GacA and RpoS

    Science.gov (United States)

    The GacA/Rsm signal transduction system and the stationary phase sigma factor RpoS have both been shown to affect secondary metabolite production and biological control in Pseudomonas protegens Pf-5 and related strains. Microarray analysis of Pf-5 grown on pea seed surfaces showed that 595 genes ar...

  8. Genome of Pseudomonas sp. FeS53a, a Putative Plant Growth-Promoting Bacterium Associated with Rice Grown in Iron-Stressed Soils.

    Science.gov (United States)

    de Souza, Rocheli; Sant'Anna, Fernando Hayashi; Ambrosini, Adriana; Tadra-Sfeir, Michele; Faoro, Helisson; Pedrosa, Fabio Oliveira; Souza, Emanuel Maltempi; Passaglia, Luciane M P

    2015-01-01

    Pseudomonas sp. FeS53a was isolated from the roots of rice plants cultivated in one area with a well-established history of iron toxicity. The FeS53a genome sequence provides the genetic basis for understanding its lifestyle and survival in association with rice in conditions of iron toxicity. PMID:25838496

  9. Genome of Pseudomonas sp. FeS53a, a Putative Plant Growth-Promoting Bacterium Associated with Rice Grown in Iron-Stressed Soils

    OpenAIRE

    de Souza, Rocheli; Sant’Anna, Fernando Hayashi; Ambrosini, Adriana; Tadra-Sfeir, Michele; Faoro, Helisson; Pedrosa, Fabio Oliveira; Souza, Emanuel Maltempi; Passaglia, Luciane M. P.

    2015-01-01

    Pseudomonas sp. FeS53a was isolated from the roots of rice plants cultivated in one area with a well-established history of iron toxicity. The FeS53a genome sequence provides the genetic basis for understanding its lifestyle and survival in association with rice in conditions of iron toxicity.

  10. 3-Fluorophenmetrazine, a fluorinated analogue of phenmetrazine: Studies on in vivo metabolism in rat and human, in vitro metabolism in human CYP isoenzymes and microbial biotransformation in Pseudomonas Putida and wastewater using GC and LC coupled to (HR)-MS techniques.

    Science.gov (United States)

    Mardal, Marie; Miserez, Bram; Bade, Richard; Portolés, Tania; Bischoff, Markus; Hernández, Félix; Meyer, Markus R

    2016-09-01

    Wastewater-based epidemiology (WBE) as means to estimate illicit drug and new psychoactive substance (NPS) consumption with spatial and temporal resolution is gaining increasing attention. In order to evaluate a given NPS using WBE, in vivo metabolism and microbial biotransformation of excretion products and unchanged compounds need evaluation. The aims of this study were to identify in vivo phase I and II metabolites of the NPS 3-fluorophenmetrazine (3-FPM) in human and rat urine and study the in vitro contribution of Cytochrome P450 (CYP) isoenzymes in phase I metabolism. Additionally, to study microbial biotransformation products (MBPs) of 3-FPM from incubations in wastewater and in a wastewater isolated Pseudomonas Putida strain. To these aims gas chromatography and liquid chromatography coupled to mass spectrometry were applied. Metabolites and MBPs were isolated from urine and microbial incubations after solid phase extraction and precipitation with or without enzymatic conjungate cleaving. The main transformation pathways were N-oxidation, aryl hydroxylation and subsequent O-methylation, alkyl hydroxylation, oxidation, and degradation of the ethyl-bridge yielding the O/N-bis-dealkylated metabolite, combinations thereof and further glucuronidation or sulfations. The main excretion products in the human urine sample were the unchanged compound and the N-oxide, and the main MBPs were the N-oxide and hydroxylation with subsequent oxidations on the alpha-methyl position. Based on these findings, the proposed strategy for WBE analysis of 3-FPM is quantitative determination of unchanged 3-FPM together with qualitative verification of a number of selected metabolites to verify consumption and rule out discharge. PMID:27372653

  11. Growth of Pseudomonas spp. in cottage cheese

    DEFF Research Database (Denmark)

    Østergaard, Nina Bjerre; Dalgaard, Paw

    spoilage microorganisms in cottage cheese can cause undesirable alterations in flavour, odour, appearance and texture. Contamination and growth of psychrotolerant pseudomonads including Pseudomonas fragi and Pseudomonas putida has been reported for cottage cheese but the influence of these bacteria on...... (pH 7.0) showed interesting results. Despite a lower pH value in the cottage cheese, compared to the dressing, more rapid growth was observed. This may be caused by insufficient amounts of oxygen in the cream dressing having a negative effect on growth of Pseudomonas spp. At 15˚C growth of...

  12. Interaction between the Bacterium Pseudomonas fluorescens strain CHA0, its genetic derivatives and vermiculite: Effects on chemical, mineralogical and mechanical properties of vermiculite

    Science.gov (United States)

    Mueller, Barbara

    2016-04-01

    Using bacteria of the strain Pseudomonas fluorescens wild type CHA0 and its genetic derivative strains CHA77, CHA89, CHA400, CHA631 and CHA661 (which differ in one gene only) the changes in chemical, mineralogical and rheological properties of the clay mineral vermiculite affected by microbial activity were studied in order to test whether the individually different production of metabolites by the genetically engineered strains may alter the clay mineral vermiculite in distinct ways. With the novel strategy of working with living wild type bacteria, their genetic derivatives and clay, the following properties of the mineral altered by the various strains of Pseudomonas fluorescens were determined: grain size, X-Ray diffraction pattern, intercrystalline swelling with glycerol, layer charge, CEC, BET surface and uptake of trace elements. Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) was used to determine the changes in major, minor and trace elements of the clay vermiculite affected by microbial activity. Among all analyzed trace elements, Fe, Mn and Cu are the most interesting. Fe and Mn are taken up from the clay mineral by all bacterial strains whereas Cu is only removed from vermiculite by strains CHA0, CHA77, CHA400 and CHA661. The latter mentioned strains all produce the antibiotics 2,4-diacetylphloroglucinol and monoacetylphloroglucinol which can complex Cu efficiently. Therefore the alteration of only one gene of the bacteria is causing significant effects on the clay mineral.

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

    Science.gov (United States)

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

    2016-01-01

    Pseudomonas has the highest number of species out of any genus of Gram-negative bacteria and is phylogenetically divided into several groups. The Pseudomonas putida phylogenetic branch includes at least 13 species of environmental and industrial interest, plant-associated bacteria, insect pathogens, and even some members that have been found in clinical specimens. In the context of the Genomic Encyclopedia of Bacteria and Archaea project, we present the permanent, high-quality draft genomes of the type strains of 3 taxonomically and ecologically closely related species in the Pseudomonas putida phylogenetic branch: Pseudomonas fulva DSM 17717(T), Pseudomonas parafulva DSM 17004(T) and Pseudomonas cremoricolorata DSM 17059(T). All three genomes are comparable in size (4.6-4.9 Mb), with 4,119-4,459 protein-coding genes. Average nucleotide identity based on BLAST comparisons and digital genome-to-genome distance calculations are in good agreement with experimental DNA-DNA hybridization results. The genome sequences presented here will be very helpful in elucidating the taxonomy, phylogeny and evolution of the Pseudomonas putida species complex. PMID:27594974

  14. Isolation of a non-fermentative bacterium, Pseudomonas aeruginosa, using intracellular carbon for denitrification and phosphorus-accumulation and relevant metabolic mechanisms.

    Science.gov (United States)

    Liu, Hui; Wang, Qin; Sun, Yanfu; Zhou, Kangqun; Liu, Wen; Lu, Qian; Ming, Caibing; Feng, Xidan; Du, Jianjun; Jia, Xiaoshan; Li, Jun

    2016-07-01

    A newly designed pilot-scale system was developed to enrich denitrifying phosphate-accumulating organisms (DNPAOs) for nitrogen and phosphorus nutrient removal synchronously. A strain of DNPAOs was isolated and its biochemical characteristics and metabolic mechanisms of this bacterial strain were analyzed. The results showed that compared with previously reported system, this newly designed system has higher removal rates of nutrients. Removal efficiencies of NH3-N, TN, TP, and COD in actual wastewater were 82.64%, 79.62%, 87.22%, and 90.41%, respectively. Metabolic activity of DNPAOs after anoxic stage in this study even reached 94.64%. Pseudomonas aeruginosa is a strain of non-fermentative DNPAOs with strong nitrogen and phosphorus removal abilities. Study on the metabolic mechanisms suggested that intracellular PHB of P. aeruginosa plays dual roles, supplying energy for phosphorus accumulation and serving as a major carbon source for denitrification. PMID:26995616

  15. The algT gene of Pseudomonas syringae pv. glycinea and new insights into the transcriptional organization of the algT-muc gene cluster.

    Science.gov (United States)

    The phytopathogenic bacterium Pseudomonas syringae pv. glycinea infects soybean plants and causes bacterial blight. In addition to P. syringae, the human pathogen Pseudomonas aeruginosa and the soil bacterium Azotobacter vinelandii produce the exopolysaccharide alginate, copolymer of D-mannuronic a...

  16. A cold-adapted and organic solvent-tolerant lipase from a psychrotrophic bacterium Pseudomonas sp. strain YY31: identification, cloning, and characterization.

    Science.gov (United States)

    Yamashiro, Yoko; Sakatoku, Akihiro; Tanaka, Daisuke; Nakamura, Shogo

    2013-10-01

    A novel cold-adapted lipase (designated as LipYY31) was obtained from a psychrotrophic Pseudomonas sp. YY31. The strain YY31 was gram-negative, rod shaped, motile by means of one polar flagellum, and exhibited chemotaxis toward oil droplets under a microscope. The strain displayed remarkable degradation of edible oil and fat even at 5 °C. The LipYY31 DNA fragment contains an open reading frame of 1,410 bp which encoded a protein of 470 amino acids with an estimated molecular mass of 49,584 Da. LipYY31 showed high sequence similarity to those of subfamily Ι.3 lipase and had a conserved GXSXG motif around the catalytic Ser residue. Its optimal temperature was 25-30 °C, and it retained 20-40 % of its activity at 0-5 °C. The optimal pH value was 8.0. The activity was strongly inhibited by Cd(2+), Zn(2+), EDTA and was highly dependent on Ca(2+). Tricaprin and p-nitrophenyl caprate were the most favorable substrates among the triglycerides and p-nitrophenyl esters, respectively. LipYY31 also had high activity towards natural substrates including edible vegetable oils and animal fat. Furthermore, LipYY31 was very active and stable in the presence of several detergents and organic solvents. In particular, the lipase exhibited high stability against organic solvents such as methanol, ethanol, and isopropanol. PMID:23918082

  17. The stack: a new bacterial structure analyzed in the Antarctic bacterium Pseudomonas deceptionensis M1(T by transmission electron microscopy and tomography.

    Directory of Open Access Journals (Sweden)

    Lidia Delgado

    Full Text Available In recent years, improvements in transmission electron microscopy (TEM techniques and the use of tomography have provided a more accurate view of the complexity of the ultrastructure of prokaryotic cells. Cryoimmobilization of specimens by rapid cooling followed by freeze substitution (FS and sectioning, freeze fracture (FF and observation of replica, or cryoelectron microscopy of vitreous sections (CEMOVIS now allow visualization of biological samples close to their native state, enabling us to refine our knowledge of already known bacterial structures and to discover new ones. Application of these techniques to the new Antarctic cold-adapted bacterium Pseudomonasdeceptionensis M1(T has demonstrated the existence of a previously undescribed cytoplasmic structure that does not correspond to known bacterial inclusion bodies or membranous formations. This structure, which we term a "stack", was mainly visualized in slow growing cultures of P. deceptionensis M1(T and can be described as a set of stacked membranous discs usually arranged perpendicularly to the cell membrane, but not continuous with it, and found in variable number in different locations within the cell. Regardless of their position, stacks were mostly observed very close to DNA fibers. Stacks are not exclusive to P. deceptionensis M1(T and were also visualized in slow-growing cultures of other bacteria. This new structure deserves further study using cryoelectron tomography to refine its configuration and to establish whether its function could be related to chromosome dynamics.

  18. Inhibition of Aspergillus fumigatus and Its Biofilm by Pseudomonas aeruginosa Is Dependent on the Source, Phenotype and Growth Conditions of the Bacterium.

    Directory of Open Access Journals (Sweden)

    Jose A G Ferreira

    Full Text Available Aspergillus fumigatus (Af and Pseudomonas aeruginosa (Pa are leading fungal and bacterial pathogens, respectively, in many clinical situations. Relevant to this, their interface and co-existence has been studied. In some experiments in vitro, Pa products have been defined that are inhibitory to Af. In some clinical situations, both can be biofilm producers, and biofilm could alter their physiology and affect their interaction. That may be most relevant to airways in cystic fibrosis (CF, where both are often prominent residents. We have studied clinical Pa isolates from several sources for their effects on Af, including testing involving their biofilms. We show that the described inhibition of Af is related to the source and phenotype of the Pa isolate. Pa cells inhibited the growth and formation of Af biofilm from conidia, with CF isolates more inhibitory than non-CF isolates, and non-mucoid CF isolates most inhibitory. Inhibition did not require live Pa contact, as culture filtrates were also inhibitory, and again non-mucoid>mucoid CF>non-CF. Preformed Af biofilm was more resistant to Pa, and inhibition that occurred could be reproduced with filtrates. Inhibition of Af biofilm appears also dependent on bacterial growth conditions; filtrates from Pa grown as biofilm were more inhibitory than from Pa grown planktonically. The differences in Pa shown from these different sources are consistent with the extensive evolutionary Pa changes that have been described in association with chronic residence in CF airways, and may reflect adaptive changes to life in a polymicrobial environment.

  19. Isolation and characterization of a novel paraffin wax-degrading bacterium, Pseudomonas sp strain PW-1, from petroleum-contaminated sites.

    Science.gov (United States)

    Zhang, Y L; Liu, Z; Liu, T

    2016-01-01

    An isolate capable of degrading paraffin wax was isolated from petroleum-contaminated sites in Daqing, China, and identified as Pseudomonas sp strain PW-1 by analyzing the 16S rDNA sequence (GenBank accession No.: KF529529) as well as the biochemical and physiological characteristics. The optimized degradation conditions of the isolate were as follows: FeSO4 metal ion concentration of 0.01 g, temperature of 30°C, (NH4)2SO4 nitrogen source concentration of 1.5 g/L, and a carbon: nitrogen ratio of 10:1. Response surface methodology-based analysis of the culture time, inoculation amount, and initial pH of the medium revealed that the optimal theoretical conditions were a culture time of 11.16 days, inoculation amount of 3.13%, and an initial pH of 9.29. The theoretical degradation rate was up to 54.68% under the optimal conditions. Taking into account the experimental conditions of a laboratory, 11.2 days of cultivating time, 3% inoculum, and a medium initial pH of 9.3 were used in practical settings. Experimental results showed that the degradation rate of paraffin wax was 52.85%, which demonstrated that this strain could degrade 1050 mg paraffin wax, using it as the sole carbon source, in a 1000-mL minimal salts medium. These results indicate that the strain PW1 can be used for application in oil wells with paraffin deposition problems in order to enhance oil recovery. PMID:27323173

  20. Biotransformation of myrcene by Pseudomonas aeruginosa

    OpenAIRE

    Hashemi Elham; Esmaeili Akbar

    2011-01-01

    Abstract Background Dihydrolinalool and terpineol are sources of fragrances that provide a unique volatile terpenoid alcohol of low toxicity and thus are widely used in the perfumery industry, in folk medicine, and in aromatherapy. They are important chemical constituents of the essential oil of many plants. Previous studies have concerned the biotransformation of limonene by Pseudomonas putida. The objective of this research was to study biotransformation of myrcene by Pseudomonas aeruginosa...

  1. Transcriptome Dynamics of Pseudomonas putida KT2440 under Water Stress

    OpenAIRE

    Gülez, Gamze; Dechesne, Arnaud; Workman, Christopher T.; Smets, Barth F

    2012-01-01

    Water deprivation can be a major stressor to microbial life in surface and subsurface soil. In unsaturated soils, the matric potential (Ψm) is often the main component of the water potential, which measures the thermodynamic availability of water. A low matric potential usually translates into water forming thin liquid films in the soil pores. Little is known of how bacteria respond to such conditions, where, in addition to facing water deprivation that might impair their metabolism, they hav...

  2. Physiology of solvent tolerance in Pseudomonas putida S12

    NARCIS (Netherlands)

    Isken, S.

    2000-01-01

    Hydrophobic organic solvents, like toluene, are toxic for living organisms. This toxicity is an important drawback in the environmental biotechnology as well as in the application of solvents in the production of fine chemicals by whole-cell biotransformations. The effects of organic solvents on mic

  3. [Plasmid characteristics of naphthalene and salicylate biodegradation in Pseudomonas putida].

    Science.gov (United States)

    Zakharian, R A; Bakunin, K A; Gasparian, N S; Kocharian, Sh M; Arakelov, G M

    1980-01-01

    The object of this work was to study the physico-chemical and biological properties of DNAs of the biodegradation plasmids NAH and SAL. A comparative analysis of the physico-chemical parameters for these DNAs made it possible to detect a number of identical properties in them: the same sedimentation profile for covalently-closed circular DNA forms, 68--70 S; the molecular weight of ca. 50 MD; a roughly equal number of fragments (up to 23) was found when the DNAs of NAH and SAL were restricted by EcoRI endonuclease. The transformation of the plasmidless strain PpGI was done. PMID:6259498

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

    DEFF Research Database (Denmark)

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

    2003-01-01

    sigma(54) is unique among the bacterial sigma factors. Besides not being related in sequence with the rest of such factors, its mechanism of transcription initiation is completely different and requires the participation of a transcription activator. In addition, whereas the rest of the alternative...... sigma factors use to be involved in transcription of somehow related biological functions, this is not the case for sigma(54) and many different and unrelated genes have been shown to be transcribed from sigma(54)-dependent promoters, ranging from flagellation, to utilization of several different carbon...... and nitrogen sources, or alginate biosynthesis. These genes have been characterized in many different bacterial species and, only until recently with the arrival of complete genome sequences, we have been able to look at the sigma(54) functional role from a genomic perspective. Aided by computational...

  5. Selection of hyperadherent mutants in Pseudomonas putida biofilms

    DEFF Research Database (Denmark)

    Yousef-Coronado, Fatima; Soriano, María Isabel; Yang, Liang;

    2011-01-01

    A number of genetic determinants required for bacterial colonization of solid surfaces and biofilm formation have been identified in different micro-organisms. There are fewer accounts of mutations that favour the transition to a sessile mode of life. Here we report the isolation of random transp...

  6. Characterization of starvation-induced dispersion in Pseudomonas putida biofilms

    DEFF Research Database (Denmark)

    Gjermansen, Morten; Ragas, Paula Cornelia; Sternberg, Claus; Molin, Søren; Tolker-Nielsen, Tim

    2005-01-01

    dissolution. PP0164 encodes a putative periplasmic protein of previously unknown function, and PP0164 mutant bacteria are sticky, and unable to reduce their adhesiveness and dissolve their biofilm in response to carbon starvation. PP0165 encodes a putative transmembrane protein containing GGDEF and EAL...... domains, and PP0165 mutant bacteria are unable to increase their adhesiveness and form biofilm. We suggest that the PP0164 and PP0165 proteins are involved in the regulation of the adhesiveness of the bacteria; the PP0165 protein through c-di-GMP signalling, and the PP0164 protein as a transducer of the...

  7. Effect of degradative plasmid CAM-OCT on responses of Pseudomonas bacteria to UV light

    International Nuclear Information System (INIS)

    The effect of plasmid CAM-OCT on responses to UV irradiation was compared in Pseudomonas aeruginosa, in Pseudomonas putida, and in Pseudomonas putida mutants carrying mutations in UV response genes. CAM-OCT substantially increased both survival and mutagenesis in the two species. P. aeruginosa strains without CAM-OCT exhibited much higher UV sensitivity than did P. putida strains. UV-induced mutagenesis of plasmid-free P. putida was easily detected in three different assays (two reversion assays and one forward mutation assay), whereas UV mutagenesis of P. aeruginosa without CAM-OCT was seen only in the forward mutation assay. These results suggest major differences in DNA repair between the two species and highlight the presence of error-prone repair functions on CAM-OCT. A number of P. putida mutants carrying chromosomal mutations affecting either survival or mutagenesis after UV irradiation were isolated, and the effect of CAM-OCT on these mutants was determined. All mutations producing a UV-sensitive phenotype in P. putida were fully suppressed by the plasmid, whereas the plasmid had a more variable effect on mutagenesis mutations, suppressing some and producing no suppression of others. On the basis of the results reported here and results obtained by others with plasmids carrying UV response genes, it appears that CAM-OCT may differ either in regulation or in the number and functions of UV response genes encoded

  8. An Investigation About the Distribution and Isolation of Pseudomonas from Raw Milk Samples Obtained from Different Areas

    OpenAIRE

    Uraz, Güven; ÇITAK, Sumru

    1998-01-01

    In this research, a total of 48 Pseudomonas had been isolated using PseudomonasCN and CFC Agar, Pseudomonas P(King A) and PseudomonasF(King B) and Crystal Violet Tetrazolium Agar (CVT) from 200 raw milk samples. Of 48 isolated Pseudomonas, (41.66%) 20 have been named as P. fluorescens, (22.51%) 11 as P. aeruginosa,22.91%) 11 as P. putida, (4.16%) 2 as P. aurefa-ciens, (6.25%) 3 as P. pseudomallei, (2.08%) 1 as P. cepacia. When the distribution of Pseudomonas species has been evaluated acc...

  9. A Novel Method for Production of 3-Hydroxydecanoic Acid by Recombinant Escherichia coli and Pseudomonas putida

    Institute of Scientific and Technical Information of China (English)

    郑重; 宫强; 陈国强

    2004-01-01

    3-hydroxydecanoic acid (3HD) is an interesting intermediate for chemical synthesis of many valuable compounds. A novel method to produce 3HD by recombinant bacteria was constructed in Escherichia coli HB101 and Pseudomonas putida GPp104, respectively. Simultaneous expression of both phaG encoding (R)-3-hydroxydecanoyl-ACP:CoA transacylase and tesB encoding thioesterase Ⅱ in E. coli HB101 increased 3HD production approximate 1.7-folds compared with the expression of phaG gene alone under identical conditions. In addition, when the tesB gene was introduced into the strain, the polyhydroxyalkanoate synthase negative strain P. putida GPpl04 produced extracellular 3HD. Thus, a novel pathway to produce 3HD by recombinant Pseudomonas was constructed. It was also found that the ratio of carbon source to nitrogen source affected the production of 3HD by recombinant P.putida harboring tesB gene. Nitrogen limitation seemed to promote the extracellular 3HD production.

  10. Polycyclic aromatic hydrocarbon degradation by biosurfactant-producing Pseudomonas sp. IR1

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, M. [Unidad de Biotecnologia del Petroleo, Centro de Biotecnologia, Fundacion Inst. de Estudios Avanzados (IDEA), Caracas (Venezuela); Synthesis and Biotics Div., Indian Oil Corp., Research and Development Center, Haryana (India); Leon, V.; Materano, A.D.S.; Ilzins, O.A.; Galindo-Castro, I.; Fuenmayor, S.L. [Unidad de Biotecnologia del Petroleo, Centro de Biotecnologia, Fundacion Inst. de Estudios Avanzados (IDEA), Caracas (Venezuela)

    2006-03-15

    We characterized a newly isolated bacterium, designated as IR1, with respect to its ability to degrade polycyclic aromatic hydrocarbons (PAHs) and to produce biosurfactants. Isolated IR1 was identified as Pseudomonas putida by analysis of 16S rRNA sequences (99.6% homology). It was capable of utilizing two-, three- and four-ring PAHs but not hexadecane and octadecane as a sole carbon and energy source. PCR and DNA hybridization studies showed that enzymes involved in PAH metabolism were related to the naphthalene dioxygenase pathway. Observation of both tensio-active and emulsifying activities indicated that biosurfactants were produced by IR1 during growth on both water miscible and immiscible substrates. The biosurfactants lowered the surface tension of medium from 54.9 dN cm{sup -1} to 35.4 dN cm{sup -1} and formed a stable and compact emulsion with an emulsifying activity of 74% with diesel oil, when grown on dextrose. These findings indicate that this isolate may be useful for bioremediation of sites contaminated with aromatic hydrocarbons. (orig.)

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

    Science.gov (United States)

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

  12. Comparison of biomass detachment from two different Pseudomonas spp. biofilms under constant shear conditions

    OpenAIRE

    Gazzola, Giulio; Habimana, Olivier; Murphy, Cormac D.; Casey, Eoin

    2015-01-01

    In the context of biofilm development, detachment is of practical importance when placed in a biofilm management perspective. The objective of the present study was to examine biofilm structure and biofilm detachment under controlled conditions for two distinct microorganisms grown under constant shear conditions. Detached biofilm biomass was regularly collected and analysed over the course of 72 h biofilm growth by Pseudomonas putida and Pseudomonas fluorescens cells, and biofilm structural ...

  13. Effect of Pseudomonas aeruginosa Pure Exotoxin A on Mice WBC in Comparison with Human WBC Contaminated by Pseudomonas aeruginosa

    OpenAIRE

    M Naghmachi; A Sharifi; J Kohanteb

    2008-01-01

    ABSTRACT Introduction & Objective: Pseudomonas aeruginosa is a gram negative bacterial. This bacterium is resistant to many antibiotics and chemical disinfectants. Pseudomonas aeruginosa is an opportunistic bacteria and caused infection in skin, external ear, upper respiratory tract, large intestine and is an important bacteria in nosocomial infections. It causes acute infection in burn disease. This bacterium can produce exotoxin A and effect on elongation factor II and can stop protein ...

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

    Directory of Open Access Journals (Sweden)

    Marta eMichalska

    2015-09-01

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

  15. Genomics of Secondary Metabolite Production by Pseudomonas fluorescens Pf-5

    Science.gov (United States)

    Pseudomonas spp. are prolific producers of secondary metabolites, and the availability of genomic sequences now opens the door for discovery of novel natural products with potential roles in the ecology and plant growth promoting properties of these bacteria. The rhizosphere bacterium Pseudomonas f...

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

    OpenAIRE

    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.

  17. Novel Targets for Treatment of Pseudomonas aeruginosa Biofilms

    DEFF Research Database (Denmark)

    Alhede, Morten; Alhede, Maria; Bjarnsholt, Thomas

    2014-01-01

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

  18. Pseudomonas sp. strain CA5 (a selenite-reducing bacterium) 16S rRNA gene complete sequence. National Institute of Health, National Center for Biotechnology Information, GenBank sequence. Accession FJ422810.1.

    Science.gov (United States)

    This study used 1321 base pair 16S rRNA gene sequence methods to confirm the phylogenetic position of a soil isolate as a bacterium belonging to the genus Pesudomonas sp. Morphological, biochemical characteristics, and fatty acid profiles are consistent with the 16S rRNA gene sequence identification...

  19. Taxonomic characterization of the cellulose-degrading bacterium NCIB 10462

    Energy Technology Data Exchange (ETDEWEB)

    Dees, C.; Ringleberg, D.; Scott, T.C. [Oak Ridge National Lab., TN (United States); Phelps, T. [Univ. of Tennessee, Knoxville, TN (United States)

    1994-06-01

    The gram negative cellulase-producing bacterium NCIB 10462 has been previously named Pseudomonas fluorescens subsp. or var. cellulosa. Since there is renewed interest in cellulose-degrading bacteria for use in bioconversion of cellulose to chemical feed stocks and fuels, we re-examined the characteristics of this microorganism to determine its proper taxonomic characterization and to further define it`s true metabolic potential. Metabolic and physical characterization of NCIB 10462 revealed that this was an alkalophilic, non-fermentative, gram negative, oxidase positive, motile, cellulose-degrading bacterium. The aerobic substrate utilization profile of this bacterium was found to have few characteristics consistent with a classification of P. fluorescens with a very low probability match with the genus Sphingomonas. Total lipid analysis did not reveal that any sphingolipid bases are produced by this bacterium. NCIB 10462 was found to grow best aerobically but also grows well in complex media under reducing conditions. NCIB 10462 grew slowly under full anaerobic conditions on complex media but growth on cellulosic media was found only under aerobic conditions. Total fatty acid analysis (MIDI) of NCIB 10462 failed to group this bacterium with a known pseudomonas species. However, fatty acid analysis of the bacteria when grown at temperatures below 37{degrees}C suggest that the organism is a pseudomonad. Since a predominant characteristic of this bacterium is it`s ability to degrade cellulose, we suggest it be called Pseudomonas cellulosa.

  20. Antimicrobial resistance of Pseudomonas spp. isolated from wastewater and wastewater-impacted marine coastal zone.

    Science.gov (United States)

    Luczkiewicz, Aneta; Kotlarska, Ewa; Artichowicz, Wojciech; Tarasewicz, Katarzyna; Fudala-Ksiazek, Sylwia

    2015-12-01

    In this study, species distribution and antimicrobial susceptibility of cultivated Pseudomonas spp. were studied in influent (INF), effluent (EFF), and marine outfall (MOut) of wastewater treatment plant (WWTP). The susceptibility was tested against 8 antimicrobial classes, active against Pseudomonas spp.: aminoglycosides, carbapenems, broad-spectrum cephalosporins from the 3rd and 4th generation, extended-spectrum penicillins, as well as their combination with the β-lactamase inhibitors, monobactams, fluoroquinolones, and polymyxins. Among identified species, resistance to all antimicrobials but colistin was shown by Pseudomonas putida, the predominant species in all sampling points. In other species, resistance was observed mainly against ceftazidime, ticarcillin, ticarcillin-clavulanate, and aztreonam, although some isolates of Pseudomonas aeruginosa, Pseudomonas fluorescens, Pseudomonas pseudoalcaligenes, and Pseudomonas protegens showed multidrug-resistance (MDR) phenotype. Among P. putida, resistance to β-lactams and to fluoroquinolones as well as multidrug resistance become more prevalent after wastewater treatment, but the resistance rate decreased in marine water samples. Obtained data, however, suggests that Pseudomonas spp. are equipped or are able to acquire a wide range of antibiotic resistance mechanisms, and thus should be monitored as possible source of resistance genes. PMID:26286796

  1. SIDEROPHORE PRODUCING Pseudomonas AS PATHOGENIC Rhisoctonia solani AND Botrytis cinerea ANTAGONISTS

    Directory of Open Access Journals (Sweden)

    Martha Páez

    2005-06-01

    Full Text Available Pseudomonas aeruginosa, Pseudomonas putida biovar B, Pseudomonas marginalis y Burkholderia cepacia, aisladas de rizosfera y filosfera de plantas de rosa y alstroemeria, identificadas por ensayos bioquímicos y cultivadas en medio King B, mostraron propiedades antagónicas contra los patógenos (se usó medio PDA agar par el cultivo Rhizoctonia solani y Botrytis cinerea. Estas propiedades coincidieron con la presencia de un sideróforo, sustancia polar con bandas de absorción en 260 nm y 402 nm. Se observó incremento del crecimiento longitudinal de las plantas, medido sobre el tallo central, por influencia de P. putida biovar B, P. aeruginosa y P. marginalis. El crecimiento de rizomas (a: 0.05 fue notorio bajo la influencia de P. marginalis.

  2. Root hairs play a key role in the endophytic colonization of olive roots by Pseudomonas spp. with biocontrol activity

    OpenAIRE

    Prieto, Pilar; Schiliro, Elisabetta; Maldonado-González, María Mercedes; Valderrama, Raquel; Barroso-Albarracín, Juan Bautista; Mercado-Blanco, Jesús

    2011-01-01

    The use of indigenous bacterial root endophytes with biocontrol activity against soil-borne phytopathogens is an environmentally-friendly and ecologically-efficient action within an integrated disease management framework. The earliest steps of olive root colonization by Pseudomonas fluorescens PICF7 and Pseudomonas putida PICP2, effective biocontrol agents (BCAs) against Verticillium wilt of olive (Olea europaea L.) caused by the fungus Verticillium dahliae Kleb., are here described. A gnoto...

  3. Self-mobilization and organization of the genes encoding the toluene metabolic pathway of Pseudomonas mendocina KR1.

    OpenAIRE

    Wright, A; Olsen, R. H.

    1994-01-01

    The toluene metabolic pathway of Pseudomonas mendocina KR1 is chromosomally encoded, but the pathway could be transferred by conjugation from strain KR1 to the chromosome of P. aeruginosa or P. putida. Such transconjugants utilized toluene, p-cresol, and p-hydroxybenzaldehyde. However, transconjugants were unable to further transfer toluene genes to other recipients unless Pseudomonas sex factor R68.45 was present in trans. Although the genes encoding the upper pathway for toluene metabolism ...

  4. Pseudomona sp-ren bidez kate ertaineko gantz azidoen esterasa ekoizteko bio-erreaktore baten operazio baldintzen eta zinetikaren azterketa

    OpenAIRE

    Manso Fraile, Mireia

    2016-01-01

    [EUS] Proiektu honen helburua esterasaren lorpena aztertzeaz gain, lorpenerako erabilitako Pseudomona putida mikroorganismoaren hartzidura aztertzea da, ondoren mikroorganismo horri dagokion parametro zinetikoak lortzeko eta erreaktore baten diseinua egin ahal izateko. Horrekin batera, hartziduran eragin dezaketen faktoreak aztertuko dira (tenperatura, aparra, aireztapena, pH …) kontrol eta monitoriazioan kontutan izateko. Horrez guztiaz gain eta prozesua erreaktorean aztertzeaz gain, matraze...

  5. Pseudomonas - Fact Sheet

    OpenAIRE

    Public Health Agency

    2012-01-01

    Fact sheet on Pseudomonas, including:What is Pseudomonas?What infections does it cause?Who is susceptible to pseudomonas infection?How will I know if I have pseudomonas infection?How can Pseudomonas be prevented from spreading?How can I protect myself from Pseudomonas?How is Pseudomonas infection treated?

  6. Mining Genomes of Biological Control Strains of Pseudomonas spp.: Unexpected Gems and Tailings

    Science.gov (United States)

    The biocontrol bacterium Pseudomonas fluorescens Pf-5 suppresses numerous soilborne plant diseases and produces an array of structurally-characterized secondary metabolites that are toxic to plant pathogenic bacteria, fungi and Oomycetes. Biosynthetic gene clusters for these metabolites compose nea...

  7. Bdellovibrio bacteriovorus HD100 guards against Pseudomonas tolaasii brown-blotch lesions on the surface of post-harvest Agaricus bisporus supermarket mushrooms

    OpenAIRE

    Saxon, Emma B; Jackson, Robert W.; Bhumbra, Shobita; Smith, Tim; Sockett, R. Elizabeth

    2014-01-01

    BACKGROUND: Pseudomonas tolaasii is a problematic pathogen of cultured mushrooms, forming dark brown 'blotches' on mushroom surfaces and causing spoilage during crop growth and post-harvest . Treating P. tolaasii infection is difficult, as other, commensal bacterial species such as Pseudomonas putida are necessary for mushroom growth, so treatments must be relatively specific. RESULTS: We have found that P. tolaasii is susceptible to predation in vitro by the δ-proteobacterium Bdello...

  8. Metabolism of glyphosate in Pseudomonas sp. strain LBr.

    OpenAIRE

    Jacob, G S; Garbow, J.R.; Hallas, L E; Kimack, N M; Kishore, G M; Schaefer, J.

    1988-01-01

    Metabolism of glyphosate (N-phosphonomethylglycine) by Pseudomonas sp. strain LBr, a bacterium isolated from a glyphosate process waste stream, was examined by a combination of solid-state 13C nuclear magnetic resonance experiments and analysis of the phosphonate composition of the growth medium. Pseudomonas sp. strain LBr was capable of eliminating 20 mM glyphosate from the growth medium, an amount approximately 20-fold greater than that reported for any other microorganism to date. The bact...

  9. Degradation of alkylphenol ethoxylates by Pseudomonas sp. strain TR01.

    OpenAIRE

    Maki, H; Masuda, N.; Fujiwara, Y; Ike, M; Fujita, M.

    1994-01-01

    An alkylphenol ethoxylate-degrading bacterium was isolated from activated sludge of a municipal sewage treatment plant by enrichment culture. This organism was found to belong to the genus Pseudomonas; since no corresponding species was identified, we designated it as Pseudomonas sp. strain TR01. This strain had an optimal temperature and pH of 30 degrees C and 7, respectively, for both growth and the degradation of Triton N-101 (a nonylphenol ethoxylate in which the average number of ethylen...

  10. Draft Genome Sequence of Pseudomonas Strain P818, Isolated from Glyphosate-Polluted Soil

    OpenAIRE

    Cao, Gaoyi; Liu, Yunjun; Liu, Guiming; Wang, Jianhua; Wang, Guoying

    2013-01-01

    Pseudomonas strain P818 was isolated from glyphosate-polluted soil in China. This bacterium presents a capacity for high glyphosate tolerance. We present the draft genome sequence of the strain Pseudomonas P818. The genes involved in the glyphosate tolerance were identified. This genomic information will facilitate the study of glyphosate tolerance mechanisms.

  11. pA506: A conjugative plasmid of the plant epiphyte Pseudomonas fluorescens A506

    Science.gov (United States)

    Pseudomonas fluorescens A506 is an plant-epiphytic bacterium that is used commercially in the United States for the biological control of fire blight disease of pear and apple. Here, we demonstrate that A506 has a 57 kB conjugative plasmid that can transfer to other strains of Pseudomonas spp. and ...

  12. Genomic Analysis of Antifungal Metabolite Production by Pseudomonas fluorescens Pf-5

    Science.gov (United States)

    The complete genomic sequences of several Pseudomonas spp. that inhabit the rhizosphere are now available, providing a new opportunity to advance knowledge of plant-growth promoting rhizobacteria through genomics. Among these is the biological control bacterium Pseudomonas fluorescens Pf-5. Nearly...

  13. Genomic Analysis of Secondary Metabolite Production by Pseudomonas fluorescens Pf-5

    Science.gov (United States)

    The complete genomic sequences of several Pseudomonas spp. that live in a commensal relationship with plants are now available. Among these is the biological control bacterium Pseudomonas fluorescens Pf-5. Nearly 6% of the 7.07 Mb genome of Pf-5 is devoted to the biosynthesis of secondary metaboli...

  14. Identification and Characterization of iron-responsive regulatory elements in Pseudomonas syringae pv tomato DC3000

    Science.gov (United States)

    Pseudomonas syringae pv. tomato DC3000 (DC3000) is a model bacterial pathogen of tomato and Arabidopsis thaliana. This bacterium must sense and respond to a variety of environmental signals and understanding how the bacterium integrates these signals into a physiological response is central to our u...

  15. Identification of quorum-sensing regulated proteins in the opportunistic pathogen Pseudomonas aeruginosa by proteomics

    DEFF Research Database (Denmark)

    Arevalo-Ferro, C.; Hentzer, Morten; Reil, G.;

    2003-01-01

    The Gram-negative bacterium Pseudomonas aeruginosa is an opportunistic human pathogen which is responsible for severe nosocomial infections in immunocompromised patients and is the major pathogen in cystic fibrosis. The bacterium utilizes two interrelated quorum-sensing (QS) systems, which rely on...

  16. 东营石油污染区微生物多样性及优势菌假单胞菌对甲苯的降解%The research of microbial diversity in Dongying petroleum contaminated zone and the degradation of toluene by advantage bacterium pseudomonas

    Institute of Scientific and Technical Information of China (English)

    张晓

    2014-01-01

    目的:随着石油及其产品对环境的污染越来越受到重视,利用土壤微生物修复方法治理石油污染土壤得到了越来越多的关注。土壤中各种微生物可以吸收、降解和转化土壤中的污染物,使污染物的浓度降低或转化为无害的物质。本实验研究了东营石油污染区微生物的多样性及假单胞菌对甲苯的降解。方法对山东东营胜利油田附近区域的土壤微生物群落通过分子生物学方法进行分析研究,用大田实验研究了假单胞菌对甲苯的降解。结果确定了不同污染程度土壤中微生物多样性的变化,证明污染程度不同的区域具有相似的优势菌群。随着污染程度变化,微生物种类有所差异。优势菌群具有良好的污染物降解能力。结论对污染区微生物多样性及菌群对有机物的降解的研究,有助于利用生物降解的方法应对有机物的污染。%Objective With more attention paid to the pollution of oil and its products to the environment,the methods using soil microorganism repair to improve petroleum contaminated soil become more and more signifi-cant.Microorganisms in the soil could absorb,degrade and transform soil pollutants,or reduce the concentration of the pollutants into harmless substance.This experiment studied the microbial diversity of Dongying oil pollution area and the degradation of toluene by pseudomonas.Methods We used molecular biology methods to study the soil microbial communities in the vicinity of the Shandong Dongying Shengli oilfield.The degradation of toluene by pseudomonas was studied by field experiment.Results We confirmed the changes of different degree of pollution in the soil microbial diversity,and the different areas have the similar advantage bacterium groups.With the chan-ges of the degree of pollution,microbial species became different.Advantage bacterium groups had good ability to degrade pollutant.Conclusion The study of microbial

  17. Efficacy of lactoferricin B in controlling ready-to-eat vegetable spoilage caused by Pseudomonas spp.

    Science.gov (United States)

    Federico, Baruzzi; Pinto, Loris; Quintieri, Laura; Carito, Antonia; Calabrese, Nicola; Caputo, Leonardo

    2015-12-23

    The microbial content of plant tissues has been reported to cause the spoilage of ca. 30% of chlorine-disinfected fresh vegetables during cold storage. The aim of this work was to evaluate the efficacy of antimicrobial peptides in controlling microbial vegetable spoilage under cold storage conditions. A total of 48 bacterial isolates were collected from ready-to-eat (RTE) vegetables and identified as belonging to Acinetobacter calcoaceticus, Aeromonas media, Pseudomonas cichorii, Pseudomonas fluorescens, Pseudomonas jessenii, Pseudomonas koreensis, Pseudomonas putida, Pseudomonas simiae and Pseudomonas viridiflava species. Reddish or brownish pigmentation was found when Pseudomonas strains were inoculated in wounds on leaves of Iceberg and Trocadero lettuce and escarole chicory throughout cold storage. Bovine lactoferrin (BLF) and its hydrolysates (LFHs) produced by pepsin, papain and rennin, were assayed in vitro against four Pseudomonas spp. strains selected for their heavy spoiling ability. As the pepsin-LFH showed the strongest antimicrobial effect, subsequent experiments were carried out using the peptide lactoferricin B (LfcinB), well known to be responsible for its antimicrobial activity. LfcinB significantly reduced (P ≤ 0.05) spoilage by a mean of 36% caused by three out of four inoculated spoiler pseudomonads on RTE lettuce leaves after six days of cold storage. The reduction in the extent of spoilage was unrelated to viable cell density in the inoculated wounds. This is the first paper providing direct evidence regarding the application of an antimicrobial peptide to control microbial spoilage affecting RTE leafy vegetables during cold storage. PMID:26453993

  18. Proteolytic inactivation of cytokines by Pseudomonas aeruginosa.

    OpenAIRE

    Parmely, M; Gale, A; Clabaugh, M.; Horvat, R; Zhou, W W

    1990-01-01

    Pseudomonas aeruginosa alkaline protease and elastase are thought to contribute to bacterial invasiveness, tissue damage, and immune suppression in animals and patients infected with the bacterium. This study examined the ability of the two proteases to inactivate a number of cytokines that mediate immune and inflammatory responses. Human recombinant gamma interferon (rIFN-gamma) and human recombinant tumor necrosis factor alpha were inactivated by both proteases. Murine rIFN-gamma was relati...

  19. Hydrolytic potential of a psychrotrophic Pseudomonas isolated from refrigerated raw milk

    Directory of Open Access Journals (Sweden)

    Ana Paula F. Corrêa

    2011-12-01

    Full Text Available The production of extracellular hydrolases by a psychrotrophic bacterium isolated from refrigerated raw milk, and identified as a Pseudomonas sp. belonging to the Pseudomonas jenssenii group, was studied. This bacterium produced proteolytic and lipolytic enzymes in all media investigated (skim milk, cheese whey, casein broth, and tryptone soy broth. High levels of α-glucosidase were produced in skim milk broth. Hydrolytic enzymes detected in skim milk broth are of particular concern, indicating that these enzymes could be produced by Pseudomonas sp. during the cold storage of raw milk, contributing to the spoilage problem in milk and dairy products.

  20. Shotgun Sequencing of the Pseudomonas syringae DC3000 Transcriptome

    Science.gov (United States)

    Pseudomonas syringae pv. tomato strain DC3000 is a bacterial plant pathogen capable of causing disease in tomatoes and Arabidopsis. The genome of this bacterium has been sequenced, however as with other genomes, accurate annotation and determination of coding vs. non-coding regions has proven to be...

  1. 深海细菌 Pseudomonas sp.bIp-2黑色素生成条件研究及其 hppD基因的克隆%Studies on the melanin production and gene cloning of hppD from the deep-sea bacterium Pseudomonas sp.bIp-2

    Institute of Scientific and Technical Information of China (English)

    韦海镧; 于丽波; 易志伟; 汤熙翔

    2014-01-01

    A melanin-producing strain was isolated from deep-sea sediment of the Atlantic Ocean and identified as Pseudomonas sp.bIp-2 by 16S rRNA gene sequencing.The study of growth and melanin production with varied culture conditions show that the melanin production in strain bIp-2 is growth-associated.The maximum yield of pig-ment was obtained after the culture attained the stationary growth phase.The temperature range for growth is 4~37℃ with optimal growth at 37℃,and the maximum melanin production was observed at 28℃.The pH range for growth is 6.0~9.0,with both optimal growth and melanin formation both being at pH 7.0.Strain bIp-2 grew in 1%~9%NaCl with a maximum melanin production at 5%NaCl.Low concentration of Fe(II)(0.05 mmol/dm3 ) can improve the production of melanin.Fe2+of more than 0.20 mmol/dm3 suppressed the melanin production and Fe2+of more than 1 .00 mmol/dm3 completely inhibited the growth of the strain.Cu2+of 0.1 mmol/dm3 had no effect to the melanin production and Cu2+of more than 0.5 mmol/dm3 inhibited the formation of melanin.Cu2+over 1 .0 mmol/dm3 completely inhibited the growth of the strain.A 1 087 bp fragment of the full-length hppD gene was amplified from the strain bIp-2.The hppD gene encoded an amino acid sequence sharing a 97%similarity with the HPPD from Pseudomonas stutzeri RCH2.These results laid a foundation to the study of the synthesis,applica-tion and ecological effect of the melanin from Pseudomonas sp.bIp-2.%从大西洋深海沉积物中分离得到1株产黑色素细菌bIp-2,16S rRNA基因序列分析表明该菌隶属于假单胞菌属(Pseudomonas),与施氏假单胞菌(P.stutzeri)有最高的16S rRNA基因序列相似性(99%).进一步对该菌的生长及产黑色素条件进行了初步研究,结果表明bIp-2在稳定生长期后期才开始大量积累黑色素;bIp-2可在4~37℃的温度范围下生长,最适生长温度为37℃,在28℃具有最高的黑色素产量;bIp-2生长的p

  2. Response of Sunflower Yield and Phytohormonal Changes to Azotobacter,Azospirillum,Pseudomonas and Animal Manure in a Chemical Free Agroecosystem

    OpenAIRE

    Maziyar, Mehran; M. Reza, Ardakani; Hamid, Madani; Mohammad , Zahedi; Mohsen, Amirabadi; Saeed, Mafakheri

    2011-01-01

    There are new trends in agriculture to move toward the low input systems with the lower application of chemical fertilizers. To reach this goal, different methods, such as the application of biofertilizers, may be used. So this experiment was conducted in 2010 at a research farm in Arak, Iran, in factorial in the form of a randomized complete block design with three replications and four factors: animal manure (M), Pseudomonas putida (P), Azotobacter chroococcum (A)and Azospirillum lipoferum ...

  3. Impact of the microscale distribution of a Pseudomonas strain introduced into soil on potential contacts with indigenous bacteria

    DEFF Research Database (Denmark)

    Dechesne, Arnaud; Pallud, C.; Bertolla, F.;

    2005-01-01

    -to-cell contact, the probability of which depends on their spatial distribution. To quantitatively characterize the microscale distribution of an introduced bacterial population and its dynamics, a gfp-tagged derivative of Pseudomonas putida KT2440 was introduced by percolation in repacked soil columns. Initially....... This could constitute an explanation to the low number of indigenous transconjugants found most of time when a plasmid-donor strain is introduced into soil....

  4. Biotransformation of myrcene by Pseudomonas aeruginosa

    Directory of Open Access Journals (Sweden)

    Hashemi Elham

    2011-05-01

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

  5. Homologous Expression of the Lipase and ABC Transporter Gene Cluster, tliDEFA, Enhances Lipase Secretion in Pseudomonas spp.

    OpenAIRE

    Ahn, Jung Hoon; Pan, Jae Gu; Rhee, Joon Shick

    2001-01-01

    The ABC transporter TliDEF was found to be an efficient secretory apparatus for extracellular lipase TliA in Pseudomonas fluorescens. For the enhanced secretion of the lipase, we tried to coexpress tliA and tliDEF in various Pseudomonas species. Whereas the coexpression of tliA and tliDEF was required for the lipase secretion in P. fragi, the expression of tliA was sufficient for the lipase secretion in P. fluorescens, P. syringae, and P. putida, indicating the existence of compatible ABC tra...

  6. Molecular Probes: A Tool for Studying Toxicity of VOCs to P.Putida F1

    Science.gov (United States)

    Singh, R.; Olson, M. S.

    2007-12-01

    Volatile Organic Compounds (VOCs) are of great concern in ground water remediation, and are generally present in the form of NAPLs in subsurface environments. Among the various treatment technologies, in situ bioremediation is one of the most effective and low-cost treatment options. Many soil bacteria are reported to degrade these organic contaminants via metabolism (using them as a source of carbon to derive energy) or co- metabolism up to certain concentrations. However, larger concentrations of these contaminants are toxic to bacteria. Thus, in order to achieve successful bioremediation, it is important to determine the optimal concentrations of various contaminants that is beneficial for the activity and survival of degrading bacteria. The purpose of this study is to develop a novel method for toxicity analyses of VOC contaminants to the soil bacteria that degrade them. The present study is based on a two-color fluorescence assay of bacterial viability which facilitates actual counting of live and dead bacteria. Pseudomonas putida F1 cells were labeled with a LIVE/DEAD® BacLightTM bacterial viability kit (Invitrogen), which consists of a mixture of two dyes, SYTO 9 and propidium iodide, each with a different ability to penetrate healthy bacterial cells. Live cells stain green whereas propidium iodide (red dye) only penetrates cells with compromised membranes that are considered dead or dying. Stained cells were exposed to different concentrations of trichloroethylene (TCE) and toluene in sealed vials. Change in the concentrations of green and red cells were monitored over the time using fluorescence microscopy. UTHSCSA ImageTool software was used to count the live and dead cells in the images. It was observed that live (green) cell concentrations decreased and dead/damaged (red) cell concentrations increased over time when cells were exposed to TCE. No significant changes were observed in control experiments. Death rate constants calculated based on live cell

  7. Transcriptional regulation of pWW0 transfer genes in Pseudomonas putida KT2440

    DEFF Research Database (Denmark)

    Lambertsen, L.M.; Molin, Søren; Kroer, N.; Thomas, C.M.

    2004-01-01

    IncP-9 transfer genes are transcribed from at least three promoter regions. The promoters for traA and traD act divergently from the region found to encode the origin of transfer, oriT. These promoters regulate expression of traA, B, and perhaps traC in one direction and traD in the other, all of...... are, as in pWWO, transcribed divergently from an operon for replication and/or stable inheritance functions, MpfR is not related to the known regulatory proteins of these other transfer systems outside those of the IncP-9 family and indeed the regulators tend to be specific for each plasmid family...

  8. Characterization of cell lysis in Pseudomonas putida induced upon expression of heterologous killing genes

    DEFF Research Database (Denmark)

    Ronchel, M.C.; Molina, L.; Witte, A.; Lutbiz, W.; Molin, Søren; Ramos, J.L.; Rodriguez, Cayo Juan Ramos

    1998-01-01

    Active biological containment systems are based on the controlled expression of killing genes. These systems are of interest for the Pseudomonadaceae because of the potential applications of these microbes as bioremediation agents and biopesticides, The physiological effects that lead to cell dea...

  9. Construction of an efficient biologically contained Pseudomonas putida strain and its survival in outdoor assays

    DEFF Research Database (Denmark)

    Molina, Lazaro; Rodriguez, Cayo Juan Ramos; Ronchel, Maria C.;

    1998-01-01

    Active biological containment systems consist of two components, a killing element designed to induce cell death and a control element which modulates the expression of the killing function. We constructed a mini-Tn5 transposon bearing a fusion of the P(lac) promoter to the gef killing gene and a...... planted and unplanted soils with and without 3-methylbenzoate. In unplanted soils the numbers of both the contained strain and the uncontained strain per gram of soil tended to decrease, but the numbers of the contained strain decreased faster in soils without 3-methylbenzoate. The decrease in the number......(6) CFU/g of soil regardless of the presence of 3-methylbenzoate. In the bulk soil the numbers of bacterial cells were 2 to 3 orders of magnitude lower. In planted soils the contained strain tended to disappear, but this tendency was more pronounced in the absence of 3-methylbenzoate and occurred faster...

  10. Proteins with GGDEF and EAL domains regulate Pseudomonas putida biofilm formation and dispersal

    DEFF Research Database (Denmark)

    Gjermansen, Morten; Ragas, Paula Cornelia; Tolker-Nielsen, Tim

    2006-01-01

    Microbial biofilm formation often causes problems in medical and industrial settings, and knowledge about the factors that are involved in biofilm development and dispersion is useful for creating strategies to control the processes. In this report, we present evidence that proteins with GGDEF an...... regulating the transition of bacteria between a roaming lifestyle and a sessile biofilm lifestyle....

  11. Isolation of a strain of Pseudomonas putida capable of metabolizing anionic detergent sodium dodecyl sulfate (SDS)

    OpenAIRE

    Kumar, A.; Chaturvedi, V.

    2011-01-01

    Background and objectives: Sodium Dodecyl Sulfate (SDS) is one of the most widely used anionic detergents. The present study deals with isolation and identification of SDS-degrading bacteria from a detergent contaminated pond situated in Varanasi city, India."nMaterials and Methods: Employing enrichment technique in minimal medium (PBM), SDS-degrading bacteria were isolated from pond water sample. Rate of degradation of SDS was studied in liquid PBM and also degradation of different conc...

  12. Differential transcriptional response to antibiotics by Pseudomonas putida DOT-T1E

    DEFF Research Database (Denmark)

    Molina-Santiago, Carlos; Daddaoua, Abdelali; Gómez Lozano, María;

    2015-01-01

    Multi-drug resistant bacteria are a major threat to humanity, especially because the current battery of known antibiotics is not sufficient to combat infections produced by these microbes. Therefore, the study of how current antibiotics act and how bacteria defend themselves against antibiotics i...

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

    Science.gov (United States)

    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. Analysis of preference for carbon source utilization among three strains of aromatic compounds degrading Pseudomonas.

    Science.gov (United States)

    Karishma, M; Trivedi, Vikas D; Choudhary, Alpa; Mhatre, Akanksha; Kambli, Pranita; Desai, Jinal; Phale, Prashant S

    2015-10-01

    Soil isolates Pseudomonas putida CSV86, Pseudomonas aeruginosa PP4 and Pseudomonas sp. C5pp degrade naphthalene, phthalate isomers and carbaryl, respectively. Strain CSV86 displayed a diauxic growth pattern on phenylpropanoid compounds (veratraldehyde, ferulic acid, vanillin or vanillic acid) plus glucose with a distinct second lag-phase. The glucose concentration in the medium remained constant with higher cell respiration rates on aromatics and maximum protocatechuate 3,4-dioxygenase activity in the first log-phase, which gradually decreased in the second log-phase with concomitant depletion of the glucose. In strains PP4 and C5pp, growth profile and metabolic studies suggest that glucose is utilized in the first log-phase with the repression of utilization of aromatics (phthalate or carbaryl). All three strains utilize benzoate via the catechol 'ortho' ring-cleavage pathway. On benzoate plus glucose, strain CSV86 showed preference for benzoate over glucose in contrast to strains PP4 and C5pp. Additionally, organic acids like succinate were preferred over aromatics in strains PP4 and C5pp, whereas strain CSV86 co-metabolizes them. Preferential utilization of aromatics over glucose and co-metabolism of organic acids and aromatics are found to be unique properties of P. putida CSV86 as compared with strains PP4 and C5pp and this property of strain CSV86 can be exploited for effective bioremediation. PMID:26316546

  15. Short ROSE-like RNA thermometers control IbpA synthesis in Pseudomonas species.

    Directory of Open Access Journals (Sweden)

    Stefanie S Krajewski

    Full Text Available The bacterial small heat shock protein IbpA protects client proteins from aggregation. Due to redundancy in the cellular chaperone network, deletion of the ibpA gene often leads to only a mild or no phenotypic defect. In this study, we show that a Pseudomonas putida ibpA deletion mutant has a severe growth defect under heat stress conditions and reduced survival during recovery revealing a critical role of IbpA in heat tolerance. Transcription of the ibpA gene depends on the alternative heat shock sigma factor σ(32. Production of IbpA protein only at heat shock temperatures suggested additional translational control. We conducted a comprehensive structural and functional analysis of the 5' untranslated regions of the ibpA genes from P. putida and Pseudomonas aeruginosa. Both contain a ROSE-type RNA thermometer that is substantially shorter and simpler than previously reported ROSE elements. Comprised of two hairpin structures only, they inhibit translation at low temperature and permit translation initiation after a temperature upshift. Both elements regulate reporter gene expression in Escherichia coli and ribosome binding in vitro in a temperature-dependent manner. Structure probing revealed local melting of the second hairpin whereas the first hairpin remained unaffected. High sequence and structure conservation of pseudomonal ibpA untranslated regions and their ability to confer thermoregulation in vivo suggest that short ROSE-like thermometers are commonly used to control IbpA synthesis in Pseudomonas species.

  16. Differential degradation of crude oil (Bonny Light) by four Pseudomonas strains

    Institute of Scientific and Technical Information of China (English)

    Oluwafemi S. Obayori; Sunday A. Adebusoye; Adams O. Adewale; Ganiyu O. Oyetibo; Odunola O. Oluyemi; Rashid A. Amokun; Matthew O. Ilori

    2009-01-01

    Four hydrocarbon degraders isolated from enriched oil- and asphalt-contaminated soils in Lagos, Nigeria, were tested for their petroleum degradation potentials.All the isolates were identified as species of Pseudomonas.Pseudomonas putida P11 demonstrated a strong ability to degrade kerosene, gasoline, diesel, engine oil and crude oil while P.aeruginosa BB3 exhibited fair degradative ability on crude oil, gasoline, engine oil, anthracene and pyrene but weak on kerosene, diesel and dibenzothiophene.Pseudomonas putida WL2 and P.aeruginosa MVL1 grew on crude oil and all its cuts tested with the latter possessing similar polycyclic aromatic potentials as P11.All the strains grew logarithmically with 1-2 orders of magnitude and with generation time ranging significantly between 3.07 and 8.55 d at 0.05 level of confidence.Strains WL2 and MVL1 utilized the oil substrate best with more than 70% in 6 d experimental period, whereas the same feat was achieved by P11 in 12 d period.BB3 on the other hand degraded only 46% within 6 d.Interestingly, data obtained from gas chromatographic analysis of oil recovered from the culture fluids of MVL1 confirmed near-disappearance of major peaks (including aliphatics and aromatics) in the hydrocarbon mixture.

  17. Bioleaching of copper oxide ore by Pseudomonas aeruginosa

    Science.gov (United States)

    Shabani, M. A.; Irannajad, M.; Azadmehr, A. R.; Meshkini, M.

    2013-12-01

    Bioleaching is an environmentally friendly method for extraction of metal from ores. In this study, bioleaching of copper oxide ore by Pseudomonas aeruginosa was investigated. Pseudomonas aeruginosa is a heterotrophic bacterium that can produce various organic acids in an appropriate culture medium, and these acids can operate as leaching agents. The parameters, such as particle size, glucose percentage in the culture medium, bioleaching time, and solid/liquid ratio were optimized. Optimum bioleaching conditions were found as follows: particle size of 150-177 μm, glucose percentage of 6%, bioleaching time of 8 d, and solid/liquid ratio of 1:80. Under these conditions, 53% of copper was extracted.

  18. The periplasmic protein TolB as a potential drug target in Pseudomonas aeruginosa.

    OpenAIRE

    Alessandra Lo Sciuto; Regina Fernández-Piñar; Lucia Bertuccini; Francesca Iosi; Fabiana Superti; Francesco Imperi

    2014-01-01

    International audience The Gram-negative bacterium Pseudomonas aeruginosa is one of the most dreaded pathogens in the hospital setting, and represents a prototype of multi-drug resistant "superbug" for which effective therapeutic options are very limited. The identification and characterization of new cellular functions that are essential for P. aeruginosa viability and/or virulence could drive the development of anti-Pseudomonas compounds with novel mechanisms of action. In this study we ...

  19. Attenuation of Pseudomonas aeruginosa biofilm formation by Vitexin: A combinatorial study with azithromycin and gentamicin

    OpenAIRE

    Das, Manash C.; Padmani Sandhu; Priya Gupta; Prasenjit Rudrapaul; Utpal C. De; Prosun Tribedi; Yusuf Akhter; Surajit Bhattacharjee

    2016-01-01

    Microbial biofilm are communities of surface-adhered cells enclosed in a matrix of extracellular polymeric substances. Extensive use of antibiotics to treat biofilm associated infections has led to the emergence of multiple drug resistant strains. Pseudomonas aeruginosa is recognised as a model biofilm forming pathogenic bacterium. Vitexin, a polyphenolic group of phytochemical with antimicrobial property, has been studied for its antibiofilm potential against Pseudomonas aeruginosa in combin...

  20. Draft Genome Sequences of Pseudomonas aeruginosa Isolates from Wounded Military Personnel

    Science.gov (United States)

    Arivett, Brock A.; Ream, Dave C.; Fiester, Steven E.; Kidane, Destaalem

    2016-01-01

    Pseudomonas aeruginosa, a Gram-negative bacterium that causes severe hospital-acquired infections, is grouped as an ESKAPE (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species) pathogen because of its extensive drug resistance phenotypes and effects on human health worldwide. Five multidrug resistant P. aeruginosa strains isolated from wounded military personnel were sequenced and annotated in this work. PMID:27516516

  1. Draft Genome Sequences of Pseudomonas aeruginosa Isolates from Wounded Military Personnel.

    Science.gov (United States)

    Arivett, Brock A; Ream, Dave C; Fiester, Steven E; Kidane, Destaalem; Actis, Luis A

    2016-01-01

    Pseudomonas aeruginosa, a Gram-negative bacterium that causes severe hospital-acquired infections, is grouped as an ESKAPE (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species) pathogen because of its extensive drug resistance phenotypes and effects on human health worldwide. Five multidrug resistant P. aeruginosa strains isolated from wounded military personnel were sequenced and annotated in this work. PMID:27516516

  2. Swimming Behavior of Pseudomonas aeruginosa Studied by Holographic 3D Tracking

    OpenAIRE

    Vater, Svenja M.; Weiße, Sebastian; Maleschlijski, Stojan; Lotz, Carmen; Koschitzki, Florian; Schwartz, Thomas; Obst, Ursula; Rosenhahn, Axel

    2014-01-01

    Holographic 3D tracking was applied to record and analyze the swimming behavior of Pseudomonas aeruginosa. The obtained trajectories allow to qualitatively and quantitatively analyze the free swimming behavior of the bacterium. This can be classified into five distinct swimming patterns. In addition to the previously reported smooth and oscillatory swimming motions, three additional patterns are distinguished. We show that Pseudomonas aeruginosa performs helical movements which were so far on...

  3. Mechanism of Enhanced Activity of Liposome-Entrapped Aminoglycosides against Resistant Strains of Pseudomonas aeruginosa

    OpenAIRE

    Mugabe, Clement; Halwani, Majed; Azghani, Ali O.; Lafrenie, Robert M.; Omri, Abdelwahab

    2006-01-01

    Pseudomonas aeruginosa is inherently resistant to most conventional antibiotics. The mechanism of resistance of this bacterium is mainly associated with the low permeability of its outer membrane to these agents. We sought to assess the bactericidal efficacy of liposome-entrapped aminoglycosides against resistant clinical strains of P. aeruginosa and to define the mechanism of liposome-bacterium interactions. Aminoglycosides were incorporated into liposomes, and the bactericidal efficacies of...

  4. Differential Effects of Permeating and Nonpermeating Solutes on the Fatty Acid Composition of Pseudomonas putida†

    OpenAIRE

    Halverson, Larry J.; Firestone, Mary K.

    2000-01-01

    We examined the effect of reduced water availability on the fatty acid composition of Pseudomonas putida strain mt-2 grown in a defined medium in which the water potential was lowered with the permeating solutes NaCl or polyethylene glycol (PEG) with a molecular weight of 200 (PEG 200) or the nonpermeating solute PEG 8000. Transmission electron microscopy showed that −1.0-MPa PEG 8000-treated cells had convoluted outer membranes, whereas −1.0-MPa NaCl-treated or control cells did not. At the ...

  5. Whole-cell bio-oxidation of n-dodecane using the alkane hydroxylase system of P. putida GPo1 expressed in E. coli

    DEFF Research Database (Denmark)

    Grant, Chris; Woodley, John; Baganz, Frank

    2011-01-01

    The alkane-1-monoxygenase (alkB) complex of Pseudomonas putida GPo1 has been extensively studied in the past and shown to be capable of oxidising aliphatic C5–C12 alkanes to primary alcohols both in the wild-type organism by growth on C5–C12 alkanes as sole carbon source and in vitro. Despite this......, successful n-dodecane oxidation for the production of 1-dodecanol or dodecanoic acid has proven elusive in the past when using alkB-expressing recombinants. This article demonstrates, for the first time in vivo, by using the Escherichia coli GEC137 pGEc47ΔJ strain, that n-dodecane oxidation using this enzyme...

  6. EFFECT OF TEMPERATURE, DIET, AND LARVAL INSTAR ON THE SUSCEPTIBILITY OF AN APHID PREDATOR, #HIPPODAMIA CONVERGENS" (COLEOPTERA:COCCINELLIDAE), TO THE WEAK BACTERIAL PATHOGEN #PSEUDOMONAS FLUORESCENS#

    Science.gov (United States)

    The authors tested the effects of larval age and stress on the susceptibility of the convergent lady beetle (Hippodamia convergens) to the weakly pathogenic bacterium Pseudomonas fluorescens. o test effects of larval age, the dose response to the bacterium was determined f or eac...

  7. Isolation of a diphenylamine-degrading bacterium and characterization of its metabolic capacities, bioremediation and bioaugmentation potential.

    Science.gov (United States)

    Perruchon, Chiara; Batianis, Christos; Zouborlis, Stelios; Papadopoulou, Evangelia S; Ntougias, Spyridon; Vasileiadis, Sotirios; Karpouzas, Dimitrios G

    2015-12-01

    The antioxidant diphenylamine (DPA) is used in fruit-packaging plants for the control of the physiological disorder apple scald. Its use results in the production of DPA-contaminated wastewater which should be treated before finally discharged. Biological treatment systems using tailored-made microbial inocula with specific catabolic activities comprise an appealing and sustainable solution. This study aimed to isolate DPA-degrading bacteria, identify the metabolic pathway of DPA and evaluate their potential for future implementation in bioremediation and biodepuration applications. A Pseudomonas putida strain named DPA1 able to rapidly degrade and utilize DPA as the sole C and N source was enriched from a DPA-contaminated soil. The isolated strain degraded spillage-level concentrations of DPA in liquid culture (2000 mg L(-1)) and in contaminated soil (1000 mg kg(-1)) and metabolized DPA via the transient formation of aniline and catechol. Further evidence for the bioremediation and biodepuration potential of the P. putida strain DPA1 was provided by its capacity to degrade the post-harvest fungicide ortho-phenylphenol (OPP), concurrently used by the fruit-packaging plants, although at slower rates and DPA in a wide range of pH (4.5-9) and temperatures (15-37 °C). These findings revealed the high potential of the P. putida strain DPA1 for use in future soil bioremediation strategies and/or as start-up inocula in wastewater biodepuration systems. PMID:26260839

  8. Chromosomal insertion of the entire Escherichia coli lactose operon, into two strains of Pseudomonas, using a modified mini-Tn5 delivery system

    DEFF Research Database (Denmark)

    Hansen, L. H.; Sørensen, S. J.; Jensen, Lars Bogø

    1997-01-01

    A 12-kb PstI fragment including the entire E. coli lactose operon (lacIPOZYA) was inserted in one copy into the chromosome of Pseudomonas putida, Pseudomonas fluorescens and an E. coli strain with lac(-) phenotype. This was made possible by improvements of an already existing mini-Tn5 transposon...... flanked by NotI sites needed in the mini-Tn5 delivery system; (b) the generation of E. coli nonlysogenic strains expressing the pi protein thus being capable of maintaining and delivering R6K-based mini-Tn5 vectors to other E. coli strains; (c) the successful insertion of the E. coli lactose operon into...

  9. The content and radiosensitivity of bacteria of Pseudomonas and Bacillus genera in soil samples from the sites adjacent to Armenian nuclear power plant

    International Nuclear Information System (INIS)

    From the samples of soils taken from the sites adjoining to the Armenian Nuclear Power Plant along the predominant direction of winds representatives of rather radiosensitive closely-related species of bacteria Pseudomonas putida and P. fluorescence and rather radioresistant bacilli B. mesentericus and B. subtilis were isolated. Their quantitative content in the soils of monitoring points and radiosensitivity was investigated. It was shown that in soils with the raised quantity of 137Cs the amount of Pseudomonas cells is understated; contrariwise their radioresistance was a little bit raised. The maintenance of cells of Bacillus species varied without certain law, and survival curves had practically identical characteristics in all the points

  10. Membrane-bound respiratory chain of Pseudomonas aeruginosa grown aerobically.

    OpenAIRE

    Matsushita, K; M. Yamada; Shinagawa, E; Adachi, O; Ameyama, M

    1980-01-01

    The electron transport chain of the gram-negative bacterium Pseudomonas aeruginosa, grown aerobically, contained a number of primary dehydrogenases and respiratory components (soluble flavin, bound flavin, coenzyme Q9, heme b, heme c, and cytochrome o) in membrane particles of the organism. Cytochrome o, about 50% of the b-type cytochrome, seemed to function as a terminal oxidase in the respiratory chain. The electron transport chain of P. aeruginosa grown aerobically was suggested to be line...

  11. Isolation of lytic phages for clinical antibiotic resistant Pseudomonas aeruginosa

    OpenAIRE

    Pires, Diana; Sillankorva, Sanna; Faustino, A.; Azeredo, Joana

    2009-01-01

    Pseudomonas aeruginosa is a relevant opportunist pathogen involved in noso-comial infections. P. aeruginosa uses an arsenal of virulence factors to cause serious infections and one of the most worrying characteristics of this bacte-rium is its low antibiotic susceptibility. The low susceptibility to antibiotics can be attributed to a concerted action of multidrug efflux pumps with chromo-somally-encoded antibiotic resistance genes and the low permeability of the bacterial cellular envelopes. ...

  12. Pseudomonas aeruginosa in the Early Childhood: A Case Report

    OpenAIRE

    Roberto Braga de CarvalhoVianna; Rodolfo de Almeida Lima Castro; Marta Lua Pimentel Winz Almeida; Andréa Gonçalves Antonio; Flávia dos Santos Moraes

    2008-01-01

    Pseudomonas aeruginosa is an opportunistic bacterium that usually affects immunocompromised patients, causing infections whose signals and symptoms are related to the affected organ. The patient presented in this article was infected when he was 9 months old. Such condition led to certain alterations like dental improperly positioned teeth, retained deciduous teeth, hipodonty of permanent teeth, atrophy of the upper jaw and dental crowding. Therefore, the purpose of this article is to report ...

  13. Pseudomonas aeruginosa in Healthcare Settings

    Science.gov (United States)

    ... CDC.gov . Healthcare-associated Infections (HAIs) Share Compartir Pseudomonas aeruginosa in Healthcare Settings On this Page What ... and/or help treat infections? What is a Pseudomonas infection? Pseudomonas infection is caused by strains of ...

  14. Antibiotic resistance patterns of Pseudomonas spp. isolated from the River Danube

    Directory of Open Access Journals (Sweden)

    Clemens eKittinger

    2016-05-01

    Full Text Available Spread and persistence of antibiotic resistance pose a severe threat to human health, yet there is still lack of knowledge about reservoirs of antibiotic resistant bacteria in the environment. We took the opportunity of the Joint Danube Survey 3 (JDS3, the world's biggest river research expedition of its kind in 2013, to analyse samples originating from different sampling points along the whole length of the river. Due to its high clinical relevance, we concentrated on the characterization of Pseudomonas spp. and evaluated the resistance profiles of Pseudomonas spp. which were isolated from eight sampling points. In total, 520 Pseudomonas isolates were found, 344 (66.0% isolates were identified as Pseudomonas putida, and 141 (27.1% as Pseudomonas fluorescens, all other Pseudomonas species were represented by less than five isolates, among those two P. aeruginosa isolates. Thirty seven percent (37% of all isolated Pseudomonas species showed resistance to at least one out of eleven tested antibiotics. The most common resistance was against meropenem (30.4% / 158 isolates piperacillin/tazobactam (10.6% / 55 isolates and ceftazidime (4.2% / 22 isolates. 16 isolates (3.1% / 16 isolates were multi-resistant. For each tested antibiotic at least one resistant isolate could be detected. Sampling points from the upper stretch of the River Danube showed more resistant isolates than downriver. Our results suggest that antibiotic resistance can be acquired by and persists even in Pseudomonas species that are normally not in direct contact with humans. A possible scenario is that these bacteria provide a reservoir of antibiotic resistance genes that can spread to related human pathogens by horizontal gene transfer.

  15. Pseudomonas screening assay

    Science.gov (United States)

    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.

  16. Recombineering Pseudomonas syringae

    Science.gov (United States)

    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...

  17. Metallo-beta-lactamases in clinical Pseudomonas isolates in Taiwan and identification of VIM-3, a novel variant of the VIM-2 enzyme.

    Science.gov (United States)

    Yan, J J; Hsueh, P R; Ko, W C; Luh, K T; Tsai, S H; Wu, H M; Wu, J J

    2001-08-01

    A total of 209 clinical isolates of Pseudomonas (193 Pseudomonas aeruginosa, 10 P. putida, 4 P. stutzeri, and 2 P. fluorescens isolates) with reduced susceptibilities to imipenem and/or ceftazidime were subjected to PCR assays with primers specific for bla(IMP-1), bla(IMP-2), bla(VIM-1), and bla(VIM-2) and sequence analysis to identify the metallo-beta-lactamases (MBLs) prevalent among these organisms in Taiwan; and 21 isolates gave positive results. Five isolates including two P. putida and three P. stutzeri isolates were found to carry bla(IMP-1), and six isolates including five P. putida and one P. stutzeri isolates harbored bla(VIM-2). The remaining 10 isolates were P. aeruginosa, and all were found to carry a novel variant of bla(VIM-2), designated bla(VIM-3). There are only two nucleotide differences between bla(VIM-2) and bla(VIM-3), leading to two amino acid alterations. Our findings indicate that VIM-2 and its variant have become the most prevalent metalloenzymes in Pseudomonas in Taiwan. Southern hybridization with the bla(VIM-2)-, bla(VIM-3)-, and bla(IMP-1 )-specific probes revealed that only two VIM-2-producing P. putida isolates appeared to carry the MBL gene on plasmids. Pulsed-field gel electrophoresis showed that six VIM-3-producing P. aeruginosa isolates and two IMP-1-producing P. stutzeri isolates were genetically related, suggesting that the spread of these MBL genes in Taiwan could be due to clonal dissemination as well as genetic exchange between different clones. PMID:11451678

  18. High-throughput identification of transcriptional start sites in Pseudomonas syringae

    Science.gov (United States)

    Pseudomonas syringae pv. tomato strain DC3000 is a bacterial plant pathogen capable of causing disease in tomatoes and Arabidopsis. The genome of this bacterium has been sequenced. However, little information is available regarding the transcriptional activity and regulation involved when this org...

  19. Gene expression profiling in viable but not culturable (VBNC) cells of Pseudomonas syringae pv syringae

    Science.gov (United States)

    Gram-negative bacterium Pseudomonas syringae infects diverse crop plants and comprises at least 50 different pathovar strains with different host ranges. One of our objectives is related to understanding molecular mechanisms of stress tolerance in alfalfa, the most widely grown forage crop in the wo...

  20. Phloroglucinol functions as an intracellular and intercellular chemical messenger influencing gene expression in Pseudomonas protegens

    Science.gov (United States)

    Bacteria can be both highly communicative and highly competitive in natural habitats and antibiotics are thought to play a role in both of these processes. The soil bacterium Pseudomonas protegens Pf-5 produces a spectrum of antibiotics, two of which, pyoluteorin and 2,4-diacetylphloroglucinol (DAP...

  1. Rhamnolipids Are Virulence Factors That Promote Early Infiltration of Primary Human Airway Epithelia by Pseudomonas aeruginosa

    OpenAIRE

    Zulianello, Laurence; Canard, Coralie; Köhler, Thilo; Caille, Dorothée; Lacroix, Jean-Silvain; Meda, Paolo

    2006-01-01

    The opportunistic bacterium Pseudomonas aeruginosa causes chronic respiratory infections in cystic fibrosis and immunocompromised individuals. Bacterial adherence to the basolateral domain of the host cells and internalization are thought to participate in P. aeruginosa pathogenicity. However, the mechanism by which the pathogen initially modulates the paracellular permeability of polarized respiratory epithelia remains to be understood. To investigate this mechanism, we have searched for vir...

  2. Pseudomonas seleniipraecipitatus sp. nov.: A selenite reducing -proteobacteria isolated from soil

    Science.gov (United States)

    Abstract: A Gram-negative, yellow pigmented bacterium designated strain CA5 that reduced selenite to elemental red selenium (Se0) was isolated from soil. 16S rRNA gene sequence alignment identified the isolate as a novel Pseudomonas sp. with P. argentinensis, P. flavescens and P. straminea as its c...

  3. The small RNA transcriptome of Pseudomonas syringae pathovar tomato DC3000

    Science.gov (United States)

    Small non-coding RNAs (ncRNAs) are regarded as important global regulators in prokaryotes and play critical roles in a variety of metabolic and cellular processes. Pseudomonas syringae pathovar tomato strain DC3000 (DC3000) is an important plant pathogenic bacterium that causes bacterial speck of to...

  4. Mobile genetic elements in the genome of the beneficial rhizobacterium Pseudomonas fluorescens Pf-5

    Science.gov (United States)

    Background: Pseudomonas fluorescens Pf-5 is a plant-associated bacterium that inhabits the rhizosphere of a wide variety of plant species and and produces secondary metabolites suppressive of fungal and oomycete plant pathogens. The Pf-5 genome is rich in features consistent with its commensal lifes...

  5. The rare codon AGA is involved in regulation of pyoluteorin biosynthesis in Pseudomonas protegens Pf-5

    Science.gov (United States)

    The soil bacterium Pseudomonas protegens Pf-5 can colonize root and seed surfaces of many plants, protecting them from infection by plant pathogenic fungi and oomycetes. This capacity to suppress disease is attributed in part to Pf-5’s production of a large spectrum of antibiotics, which is controll...

  6. Genomics-guided discovery of secondary metabolites and their regulation in Pseudomonas protegens Pf-5

    Science.gov (United States)

    Pseudomonas protegens strain Pf-5 is a well-characterized rhizosphere bacterium known for its production of a diverse spectrum of secondary metabolites and its capacity to suppress plant diseases caused by soilborne fungal, bacterial and oomycete pathogens. Metabolites produced by Pf-5 include 2,4-...

  7. TonB-Dependent outer-membrane proteins and siderophore utilization in Pseudomonas fluorescens Pf-5

    Science.gov (United States)

    The soil bacterium Pseudomonas fluorescens Pf-5 produces two siderophores, a pyoverdine and enantio-pyochelin, and its proteome includes 45 TonB-dependent outer-membrane proteins, which commonly function in uptake of siderophores and other substrates from the environment. The 45 proteins share the ...

  8. Mobile genetic elements in the genome of the beneficial rhizobacterium Pseudomonas fluorescens Pf-5

    Science.gov (United States)

    Pseudomonas fluorescens Pf-5 is a plant-associated bacterium that inhabits the rhizosphere of a wide variety of plant species and produces secondary metabolites suppressive of fungal and oomycete plant pathogens. The Pf-5 genome is rich in features consistent with its commensal lifestyle, but has re...

  9. Commensal Pseudomonas Species Isolated from Wastewater and Freshwater Milieus in the Eastern Cape Province, South Africa, as Reservoir of Antibiotic Resistant Determinants

    Directory of Open Access Journals (Sweden)

    Anthony I. Okoh

    2012-07-01

    Full Text Available Pseudomonas species are opportunistic pathogens with implications in a wide range of diseases including cystic fibrosis and sickle cell anaemia. Because of their status as multidrug resistant (MDR and extremely drug resistant (XDR bacteria Pseudomonas species represent a threat to public health. Prevalence, antibiogram and associated antibiotic resistant genes of Pseudomonas species isolated from freshwater and mixed liquor environments in the Eastern Cape Province of South Africa were assessed. Polymerase chain reaction (PCR based technique was used to identify the isolates and screen for antibiotic resistant genes. The result shows occurrence of Pseudomonas spp. in freshwater and mixed liquor as follows: 71.42% and 37.5% (P. putida, 14.28% and 31.25% (P. flourescens, 7.14% and 6.25% (P. aeruginosa and 7.14% and 25% for other Pseudomonas species respectively. Disk diffusion antibiogram of the Pseudomonas isolates from the two locations showed 100% resistance to penicillin, oxacillin, clindamycin, rifampicin and 100% susceptibility to ciprofloxacin and gentamicin with varied percentage resistances to cephalothin, nalidixic acid, tetracycline, and ampicillin. The blaTEM antibiotic resistant gene was detected in 12.5% of P. putida, 57.14% of P. fluorescens, 100% P. aeruginosa and 40% in other Pseudomonas species. Similarly, Integrons conserved segment were detected in 12.5% of P. putida, 57.14% of P. fluorescens, 100% of P. aeruginosa and 40% of other Pseudomonas species. The presence of blaTEM gene and integrons conserved segment in some of the isolates is worrisome and suggest Pseudomonas species as important reservoirs of multidrug resistance genes in the Eastern Cape Province environment.

  10. Investigation of Causer of Tomato Pith Necrosis - Pseudomonas Mediterranea Cattara Et Al. 2002, In Republic Of Macedonia

    OpenAIRE

    Kovacevik, Biljana

    2010-01-01

    Last several years from 2005 – 2009 the health condition of tomato plants is monitored in the region of Strumica. During this period, symptoms of Tomato Pith Necrosis – TPN, are observed for the first time at tomatoes grown in plasticgreen houses. A ubiquitous bacterium Pseudomonas mediterranea is isolated by standard procedure from the symptomatic tomato plants. Several years later, in 2009 the same bacterium is isolated from the soil, too. A total number of 22 isolates are investigated: ...

  11. Class 1 integrons and tetracycline resistance genes in Alcaligenes, Arthrobacter, and Pseudomonas spp. isolated from pigsties and manured soil

    DEFF Research Database (Denmark)

    Agersø, Yvonne; Sandvang, Dorthe

    2005-01-01

    The presence of tetracycline resistance (Tc-r) genes and class I integrons (in-1), and their ability to cotransfer were investigated in Tc-r gram-negative (185 strains) and gram-positive (72 strains) bacteria from Danish farmland and pigsties. The isolates belonged to the groups or species...... and/or Pseudomonas putida. We conclude that soil bacteria in close contact to manure or pigsty environment may thus have an important role in horizontal spread of resistance. Use of tetracyclines in food animal production may increase not only Tc-r but also multidrug resistance (caused by the presence...

  12. Indicator For Pseudomonas Bacteria

    Science.gov (United States)

    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.

  13. Effect of Pseudomonas aeruginosa Pure Exotoxin A on Mice WBC in Comparison with Human WBC Contaminated by Pseudomonas aeruginosa

    Directory of Open Access Journals (Sweden)

    M Naghmachi

    2008-12-01

    Full Text Available ABSTRACT Introduction & Objective: Pseudomonas aeruginosa is a gram negative bacterial. This bacterium is resistant to many antibiotics and chemical disinfectants. Pseudomonas aeruginosa is an opportunistic bacteria and caused infection in skin, external ear, upper respiratory tract, large intestine and is an important bacteria in nosocomial infections. It causes acute infection in burn disease. This bacterium can produce exotoxin A and effect on elongation factor II and can stop protein synthesis. The aim of this study was to evaluate the effect of exotoxin A on mice WBC and comparison of the results with human WBC that contaminated with Pseudomonas aeruginosa. Materials & Methods: This is an experimental study which was conducted in 1384 on burn disease patients referred to Shiraz Ghotbodin hospital. Sample that contaminated with PA was taken from these patients for WBC count and WBC differentiation. Sample was also taken from 100 burn patients without infection (50 male and 50 female. Toxigenic strain of PA103 was cultured on liquid media and used for purification of exotoxin A. This sample was injected to 50 mice (I.V and after different incubation time, WBC was counted. Ten normal mice was used as control. Collected data analyzed by SPSS. Results: WBC count decreased in mice that received Pseudomonas aeruginosa exotoxin A in comparison with normal mice (P<0.05. WBC count was significantly decreased in burn patients in comparison with normal individuals (P<0.029 and most decrease was belonged to PMN. Conclusion: The results demonstrated that Pseudomonas aeruginosa that produce exotoxin induce WBC decrease in burn disease and also in mice that contaminated with exotoxin of this bacteria. It can be concluded that bacterial infection in burn patients is toxigenic strain of PA that produce exotoxin A.

  14. Degradation of alkylphenol ethoxylates by Pseudomonas sp. strain TR01.

    Science.gov (United States)

    Maki, H; Masuda, N; Fujiwara, Y; Ike, M; Fujita, M

    1994-07-01

    An alkylphenol ethoxylate-degrading bacterium was isolated from activated sludge of a municipal sewage treatment plant by enrichment culture. This organism was found to belong to the genus Pseudomonas; since no corresponding species was identified, we designated it as Pseudomonas sp. strain TR01. This strain had an optimal temperature and pH of 30 degrees C and 7, respectively, for both growth and the degradation of Triton N-101 (a nonylphenol ethoxylate in which the average number of ethylene oxide [EO] units is 9.5). The strain was unable to mineralize Triton N-101 but was able to degrade its EO chain exclusively. The resulting dominant intermediate was identified by normal-phase high-performance liquid chromatography (HPLC) and gas chromatography-mass spectrometry as a nonylphenol ethoxylate with 2 mol of EO units. A carboxylated metabolite, [(nonylphenoxy)ethoxy]acetic acid, was detected by gas chromatography-mass spectrometry. This bacterium also metabolized alcohol ethoxylates with various numbers of EO units but not polyethylene glycols whatever their degree of polymerization. By oxygen consumption assay, the alkyl group or arene corresponding to the hydrophobic part of alcohol ethoxylates or alkylphenol ethoxylates was shown to contribute to the induction of the metabolic system of the EO chain of Triton N-101, instead of the EO chain itself, which corresponds to its hydrophilic part. Thus, the isolated pseudomonad bacterium has unique substrate assimilability: it metabolizes the EO chain only when the chain linked to bulky hydrophobic groups. PMID:8074508

  15. Lactococcus lactis - a diploid bacterium

    DEFF Research Database (Denmark)

    Michelsen, Ole; Hansen, Flemming G.; Jensen, Peter Ruhdal

    In contrast to higher eukaryotes, bacteria are haploid, i.e. they store their genetic information in a single chromosome, which is then duplicated during the cell cycle. If the growth rate is sufficiently low, the bacterium is born with only a single copy of the chromosome, which gets duplicated...... before the bacterium divides. Fast-growing bacteria have overlapping rounds of replication, and can contain DNA corresponding to more than four genome equivalents. However, the terminus region of the chromosome is still present in just one copy after division, and is not duplicated until right before...... the next division. Thus, the regions of the chromosome that are the last to be replicated are haploid even in fast-growing bacteria. In contrast to this general rule for bacteria, we found that Lactococcus lactis, a bacterium which has been exploited for thousands of years for the production of fermented...

  16. 40 CFR 180.1114 - Pseudomonas fluorescens A506, Pseudomonas fluorescens 1629RS, and Pseudomonas syringae 742RS...

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Pseudomonas fluorescens A506, Pseudomonas fluorescens 1629RS, and Pseudomonas syringae 742RS; exemptions from the requirement of a tolerance... Tolerances § 180.1114 Pseudomonas fluorescens A506, Pseudomonas fluorescens 1629RS, and Pseudomonas...

  17. Single Bacterium Detection Using Sers

    Science.gov (United States)

    Gonchukov, S. A.; Baikova, T. V.; Alushin, M. V.; Svistunova, T. S.; Minaeva, S. A.; Ionin, A. A.; Kudryashov, S. I.; Saraeva, I. N.; Zayarny, D. A.

    2016-02-01

    This work is devoted to the study of a single Staphylococcus aureus bacterium detection using surface-enhanced Raman spectroscopy (SERS) and resonant Raman spectroscopy (RS). It was shown that SERS allows increasing sensitivity of predominantly low frequency lines connected with the vibrations of Amide, Proteins and DNA. At the same time the lines of carotenoids inherent to this kind of bacterium are well-detected due to the resonance Raman scattering mechanism. The reproducibility and stability of Raman spectra strongly depend on the characteristics of nanostructured substrate, and molecular structure and size of the tested biological object.

  18. Hot Tub Rash (Pseudomonas Folliculitis)

    Science.gov (United States)

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

  19. Plant growth promoting potential of pseudomonas sp. SP0113 isolated from potable water from a closed water well

    OpenAIRE

    Przemieniecki Wojciech Sebastian; Kurowski Paweł Tomasz; Karwowska Anna

    2015-01-01

    The Pseudomonas sp. SP0113 strain from a partially closed aquatic environment was identified as a plant growth promoting bacterium (PGPB). Laboratory tests revealed that PS0113 has multiple plant growth promoting traits, including mineral phosphate solubilizing ability, ammonifying ability that increases nitrogen availability for plants via the root system, and phosphatase activity that plays an important role in organic phosphorus mineralization. Tricalciu...

  20. Roles of Rhizoxin and 2,4-diacetylphloroglucinol in Suppression of Fusarium spp. by the Rhizobacterium Pseudomonas fluorescens Pf-5

    Science.gov (United States)

    Pseudomonas fluorescens strain Pf-5 is a rhizosphere bacterium that acts as a biocontrol agent of soilborne plant diseases and produces at least 10 different secondary metabolites, including several with antifungal properties. We derived site-directed mutants of Pf-5 with single and multiple mutatio...

  1. Expression of the recA gene of Pseudomonas aeruginosa PAO is inducible by DNA-damaging agents

    Energy Technology Data Exchange (ETDEWEB)

    Miller, R.V.; Kokjohn, T.A.

    1988-05-01

    Western (immunoblot) analysis using Escherichia coli anti-RecA antiserum revealed that expression of the RecA protein of Pseudomonas aeruginosa PAO is induced upon exposure of the bacterium to UV irradiation or norfloxacin, a quinolone related to nalidixic acid.

  2. Pseudomonas aeruginosa colonization in patients with cystic fibrosis; population structure, the Dutch clone and effects of segregation

    NARCIS (Netherlands)

    Mansfeld, R. van

    2014-01-01

    More than half of the patients with cystic fibrosis (CF) are infected with Pseudomonas aeruginosa in their lungs. It was thought that patients acquired unique strains of this bacterium from the environment, however in the last decades epidemic clones have been described in other countries that are m

  3. Reduction of Chromium(VI) by Locally Isolated Pseudomonas sp. C-171

    OpenAIRE

    Rahman, Mujeeb Ur; GUL, Shereen; HAQ, Mohammad Zahoor UL

    2007-01-01

    A strain of Pseudomonas sp. C-171 capable of tolerating hexavalent chromium (Cr+6) up to 2000 ppm as potassium dichromate was isolated from domestic sewage. The Cr+6 reduction was checked by growing the isolated strain in a medium containing potassium dichromate as Cr+6 source. The rate of growth of Pseudomonas sp. C-171 decreased with the increase in Cr+6 concentration of the medium. The maximum rate of chromium reduction was observed during the log phase of bacterium growth. The reduction o...

  4. Physiological engineering of Pseudomonas aurantiaca antimicrobial activity: effects of sodium chloride treatment

    Directory of Open Access Journals (Sweden)

    Linda Rozenfelde

    2012-12-01

    Full Text Available The influence of sodium chloride (NaCl treatment on the antifungal activity of the bacterium Pseudomonas aurantiaca, a producer of biopesticide for vegetable plants, was investigated. It was shown that an increase in the NaCl concentration in incubation solutions from 1 M to 3 M led to a significant increase in the antifungal activity of this bacterium. Antifungal activity continued to increase with prolonged treatment of bacteria in fresh nutrient medium from 72 h to 96 h. These findings could be very important for the further development of biotechnological processes directed not only to the production of new active biopesticides but also of other valuable resources.

  5. Polysaccharide degradation systems of the saprophytic bacterium Cellvibrio japonicus.

    Science.gov (United States)

    Gardner, Jeffrey G

    2016-07-01

    Study of recalcitrant polysaccharide degradation by bacterial systems is critical for understanding biological processes such as global carbon cycling, nutritional contributions of the human gut microbiome, and the production of renewable fuels and chemicals. One bacterium that has a robust ability to degrade polysaccharides is the Gram-negative saprophyte Cellvibrio japonicus. A bacterium with a circuitous history, C. japonicus underwent several taxonomy changes from an initially described Pseudomonas sp. Most of the enzymes described in the pre-genomics era have also been renamed. This review aims to consolidate the biochemical, structural, and genetic data published on C. japonicus and its remarkable ability to degrade cellulose, xylan, and pectin substrates. Initially, C. japonicus carbohydrate-active enzymes were studied biochemically and structurally for their novel polysaccharide binding and degradation characteristics, while more recent systems biology approaches have begun to unravel the complex regulation required for lignocellulose degradation in an environmental context. Also included is a discussion for the future of C. japonicus as a model system, with emphasis on current areas unexplored in terms of polysaccharide degradation and emerging directions for C. japonicus in both environmental and biotechnological applications. PMID:27263016

  6. Pseudomonas aeruginosa biofilm infections

    DEFF Research Database (Denmark)

    Tolker-Nielsen, Tim

    2014-01-01

    use of conventional antimicrobial compounds in many cases cannot eradicate biofilms, there is an urgent need to develop alternative measures to combat biofilm infections. The present review is focussed on the important opportunistic pathogen and biofilm model organism Pseudomonas aeruginosa. Initially...

  7. Regulation of Glucose Metabolism in Pseudomonas: THE PHOSPHORYLATIVE BRANCH AND ENTNER-DOUDOROFF ENZYMES ARE REGULATED BY A REPRESSOR CONTAINING A SUGAR ISOMERASE DOMAIN*

    OpenAIRE

    Daddaoua, Abdelali; Krell, Tino; Ramos, Juan-Luis

    2009-01-01

    In Pseudomonas putida, genes for the glucose phosphorylative pathway and the Entner-Doudoroff pathway are organized in two operons; one made up of the zwf, pgl, and eda genes and another consisting of the edd, glk, gltR2, and gltS genes. Divergently with respect to the edd gene is the gap-1 gene. Expression from Pzwf, Pedd, and Pgap is modulated by HexR in response to the availability of glucose in the medium. To study the regulatory process in greater detail we purified HexR and showed that ...

  8. Role of Ca resistance in competitive survival of fluorescent Pseudomonas in soil with high salinity

    International Nuclear Information System (INIS)

    The Ca2+-resistant strain HR2-6 of Pseudomonas putida was isolated from spinach root grown in a greenhouse in high salinity soil. Since Ca often accumulates in greenhouse soils in Japan due to many years of Ca applications, the role of Ca2+ resistance in the survival of the strain was investigated. To conduct the investigation, Ca2+-sensitive mutants were obtained with UV-irradiation. The Ca2+-sensitive mutant CAS-1 was found to grow as well as the wild type HR2-6 in a TSB medium without added Ca2+, but with 150 mM and 200 mM Ca2+ added, the growth of the Ca2+-sensitive mutants were 7- and 56-fold lower than that of the wild type. In sterile spinach-greenhouse soil (a non-competitive environment), populations of the Ca2+-sensitive mutant and wild-type strain were similar, but in nonsterile greenhouse soil (a competitive environment), populations of the Ca2+-sensitive mutant were 112-fold lower than the wild type after 50 days. These data suggest that Ca2+ resistance can be an important factor in the survival of P. putida in soil that has an accumulation of Ca

  9. Arsenic-contaminated soils. Genetically modified Pseudomonas spp. and their arsenic-phytoremediation potential

    Energy Technology Data Exchange (ETDEWEB)

    Sizova, O.I.; Kochetkov, V.V.; Validov, S.Z.; Boronin, A.M. [Inst. of Biochemistry and Physiology of Microorganisms, Russian Academy of Sciences, Moscow (Russian Federation); Kosterin, P.V.; Lyubun, Y.V. [Inst. of Biochemistry and Physiology of Plants and Microorganisms, Russian Academy of Sciences, Saratov (Russian Federation)

    2002-07-01

    Sorghum was inoculated with Pseudomonas bacteria, including strains harboring an As-resistance plasmid, pBS3031, to enhance As-extraction by the plants. Pseudomonas strains (P. fluorescens 38a, P. putida 53a, and P. aureofaciens BS1393) were chosen because they are antagonistic to a wide range of phytopathogenic fungi and bacteria, and they can stimulate plant growth. The resistance of natural rhizospheric pseudomonads to sodium arsenite was assessed. Genetically modified Pseudomonas strains resistant to As(III)/As(V) were obtained via conjugation or transformation. The effects of the strains on the growth of sorghum on sodium-arsenite-containing soils were assessed. The conclusions from this study are: (1) It is possible to increase the survivability of sorghum growing in sodium-arsenite-containing soil by using rhizosphere pseudomonads. (2) The presence of pBS3031 offers the strains a certain selective advantage in arsenite-contaminated soil. (3) The presence of pBS3031 impairs plant growth, due to the As-resistance mechanism determined by this plasmid: the transformation of the less toxic arsenate into the more toxic, plant-root-available arsenite by arsenate reductase and the active removal of arsenite from bacterial cells. (4) Such a mechanism makes it possible to develop a bacteria-assisted phytoremediation technology for the cleanup of As-contaminated soils and is the only possible way of removing the soil-sorbed arsenates from the environment. (orig.)

  10. Characterization of a Pseudomonas putida rough variant evolved in a mixed species biofilm with Acinetobacter sp. strain C6

    DEFF Research Database (Denmark)

    Hansen, Susse Kirkelund; Haagensen, Janus Anders Juul; Gjermansen, Morten; Jørgensen, Thomas Martini; Tolker-Nielsen, Tim; Molin, Søren

    2007-01-01

    shown to evolve rapidly by natural selection of better-adapted variants in a mixed-species biofilm consortium (S. K. Hansen, P. B. Rainey, J. A. Haagensen, and S. Molin, Nature 445:533-536, 2007). Adaptation was caused by mutations in a wapH homolog (PP4943) involved in core lipopolysaccharide...

  11. Pseudomonas putida mt-2 tolerates reactive oxygen species generated during matric stress by inducing a major oxidative defense response

    OpenAIRE

    Svenningsen, Nanna Bygvraa; Pérez-Pantoja, Danilo; Nikel, Pablo I.; Nicolaisen, Mette Haubjerg; Lorenzo, Víctor de; Nybroe, Ole

    2015-01-01

    Background Soil bacteria typically thrive in water-limited habitats that cause an inherent matric stress to the cognate cells. Matric stress gives rise to accumulation of intracellular reactive oxygen species (ROS), which in turn may induce oxidative stress, and even promote mutagenesis. However, little is known about the impact of ROS induced by water limitation on bacteria performing important processes as pollutant biodegradation in the environment. We have rigorously examined the physiolo...

  12. Bioaugmentation of a sequencing batch reactor with Pseudomonas putida ONBA-17, and its impact on reactor bacterial communities

    International Nuclear Information System (INIS)

    This study demonstrates the feasibility of using Pseudomonasputida ONBA-17 to bioaugment a sequencing batch reactor (SBR) treating o-nitrobenzaldehyde (ONBA) synthetic wastewater. To monitor its survival, the strain was chromosomally marked with gfp gene. After a transient adaptation, almost 100% degradation of ONBA was obtained within 8 days as compared with 23.47% of the non-inoculated control. The bioaugmented reactor has a better chemical oxygen demand (COD) removal performance (96.28%) than that (79.26%) of the control. The bioaugmentation not only enhanced the removal capability of target compound, but shortened system start-up time. After the increase in ONBA load, performance fluctuation of two reactors was observed, and the final treating effects of them were comparable. What is more, denaturing gradient gel electrophoresis (DGGE) analysis of 16S rRNA genes via a combination of pattern comparison and sequence phylogenetic analysis was performed to uncover changes in sludge microbial communities. Only the members of alpha, beta and gamma subdivisions of Proteobacteria were identified. To isolate ONBA-degrading relevant microorganisms, spread plate was used and four bacterial strains were obtained. Subsequent systematic studies on these bacteria characterized their traits which to some extent explained why such bacteria could be kept in the system. This study will help future research in better understanding of the bioreactor bioaugmentation.

  13. Toxicities effects of pharmaceutical, olive mill and textile wastewaters before and after degradation by Pseudomonas putida mt-2

    OpenAIRE

    Mansour Hedi; Dellai Afef; Ayed Yosra

    2012-01-01

    Abstract Background Removal of numerous classes of chemical pollutants from the industrial wastewater such as textile, pharmaceutical and olive mill using conventional wastewater treatment, is incomplete and several studies suggested that improvement of this situation would require the application of biological treatment techniques. Dyes, polyphenols and drugs are an environmental pollutants extremely toxics to plants and other living organisms including humans. These effluents were previousl...

  14. Activity of toluene-degrading Pseudomonas putida in the early growth phase of a biofilm for waste gas treatment

    DEFF Research Database (Denmark)

    Pedersen, A.R.; Møller, S.; Molin, S.;

    1997-01-01

    A biological trickling filter for treatment of toluene-containing waste gas was studied. The overall kinetics of the biofilm growth was followed in the early growth phase. A rapid initial colonization took place during the first three days. The biofilm thickness increased exponentially, whereas t...

  15. Integrated Bioprocessing for the pH-Dependent Production of 4-Valerolactone from Levulinate in Pseudomonas putida KT2440 ▿

    OpenAIRE

    Martin, Collin H.; Wu, Danyi; Prather, Kristala L. Jones

    2009-01-01

    Enzymes are powerful biocatalysts capable of performing specific chemical transformations under mild conditions, yet as catalysts they remain subject to the laws of thermodynamics, namely, that they cannot catalyze chemical reactions beyond equilibrium. Here we report the phenomenon and application of using extracytosolic enzymes and medium conditions, such as pH, to catalyze metabolic pathways beyond their intracellular catalytic limitations. This methodology, termed “integrated bioprocessin...

  16. Integrated Bioprocessing for the pH-Dependent Production of 4- Levulinate in Pseudomonas putida KT2440

    OpenAIRE

    Martin, Collin H.; Wu, Danyi; Prather, Kristala L. Jones

    2009-01-01

    Enzymes are powerful biocatalysts capable of performing specific chemical transformations under mild conditions, yet as catalysts they remain subject to the laws of thermodynamics, namely, that they cannot catalyze chemical reactions beyond equilibrium. Here we report the phenomenon and application of using extracytosolic enzymes and medium conditions, such as pH, to catalyze metabolic pathways beyond their intracellular catalytic limitations. This methodology, termed “integrated bioprocessin...

  17. Indoleacetic acid operon of Pseudomonas syringae subsp. savastanoi: transcription analysis and promoter identification.

    OpenAIRE

    Gaffney, T D; da Costa e Silva, O.; Yamada, T.; Kosuge, T

    1990-01-01

    Expression of the indoleacetic acid (iaa) operon, which contributes to the virulence of the phytopathogenic bacterium Pseudomonas syringae subsp. savastanoi, was monitored by using broad-host-range lacZ reporter gene plasmids. A combination of translational (gene) fusions and transcriptional (operon) fusions of P. syringae subsp. savastanoi sequences to lacZ allowed localization of the iaa operon promoter. RNA recovered from P. syringae subsp. savastanoi strains was mapped with iaa operon-spe...

  18. Secondary Metabolites of Pseudomonas fluorescens CHA0 Drive Complex Non-Trophic Interactions with Bacterivorous Nematodes

    OpenAIRE

    Neidig, Nina; Paul, Rüdiger; Scheu, Stefan; Jousset, Alexandre

    2011-01-01

    Non-trophic interactions are increasingly recognised as a key parameter of predator–prey interactions. In soil, predation by bacterivorous nematodes is a major selective pressure shaping soil bacterial communities, and many bacteria have evolved defence mechanisms such as toxicity. In this study, we show that extracellular secondary metabolites produced by the model soil bacterium Pseudomonas fluorescens CHA0 function as a complex defence strategy against bacterivorous nematodes. Using a coll...

  19. Quorum Sensing Is Accompanied by Global Metabolic Changes in the Opportunistic Human Pathogen Pseudomonas aeruginosa

    OpenAIRE

    Davenport, Peter W.; Griffin, Julian L.; Welch, Martin

    2015-01-01

    Pseudomonas aeruginosa uses N-acyl-homoserine lactone (AHL)-dependent quorum sensing (QS) systems to control the expression of secreted effectors. These effectors can be crucial to the ecological fitness of the bacterium, playing roles in nutrient acquisition, microbial competition, and virulence. In this study, we investigated the metabolic consequences of AHL-dependent QS by monitoring the metabolic profile(s) of a lasI rhlI double mutant (unable to make QS signaling molecules) and its wild...

  20. In vitro and in vivo screening for novel essential cell-envelope proteins in Pseudomonas aeruginosa

    OpenAIRE

    Regina Fernández-Piñar; Alessandra Lo Sciuto; Alice Rossi; Serena Ranucci; Alessandra Bragonzi; Francesco Imperi

    2015-01-01

    The Gram-negative bacterium Pseudomonas aeruginosa represents a prototype of multi-drug resistant opportunistic pathogens for which novel therapeutic options are urgently required. In order to identify new candidates as potential drug targets, we combined large-scale transposon mutagenesis data analysis and bioinformatics predictions to retrieve a set of putative essential genes which are conserved in P. aeruginosa and predicted to encode cell envelope or secreted proteins. By generating unma...

  1. Effects of azithromycin on Pseudomonas aeruginosa isolates from catheter-associated urinary tract infection

    OpenAIRE

    Xu, Zhi-Gang; Gao, Yu; He, Jian-Guo; Xu, Wei-Feng; Jiang, Mei; JIN, HUAN-SHENG

    2014-01-01

    Pseudomonas aeruginosa is a common pathogenic bacterium in urinary tract infections (UTIs), particularly catheter-associated UTIs. The aim of this study was to investigate the effect of azithromycin (AZM) on P. aeruginosa isolated from UTIs. Isolates were identified by biochemical assays and the Vitek system. Antimicrobial susceptibility was determined using the disk diffusion assay. Biofilm formation and adhesion were assayed using a crystal violet staining method. The swimming motility was ...

  2. Clustering of Pseudomonas aeruginosa transcriptomes from planktonic cultures, developing and mature biofilms reveals distinct expression profiles

    OpenAIRE

    Saqi Mansoor; Hurst Jacob M; Papakonstantinopoulou Anastasia; Paccanaro Alberto; Waite Richard D; Littler Eddie; Curtis Michael A

    2006-01-01

    Abstract Background Pseudomonas aeruginosa is a genetically complex bacterium which can adopt and switch between a free-living or biofilm lifestyle, a versatility that enables it to thrive in many different environments and contributes to its success as a human pathogen. Results Transcriptomes derived from growth states relevant to the lifestyle of P. aeruginosa were clustered using three different methods (K-means, K-means spectral and hierarchical clustering). The culture conditions used fo...

  3. Use of Arabidopsis thaliana and Pseudomonas syringae in the Study of Plant Disease Resistance and Tolerance

    OpenAIRE

    Bent, Andrew F.; Kunkel, Barbara N.; Innes, Roger W.; Staskawicz, Brian J.

    1993-01-01

    The interaction between Arabidopsis thaliana and the bacterium Pseudomonas syringae is being developed as a model experimental system for plant pathology research. Race-specific ("gene-for-gene") resistance has been demonstrated for this interaction, and pathogen genes that determine avirulence have been isolated and characterized. Because certain lines of both Arabidopsis and soybean are resistant to bacteria carrying the avirulence genes avrRpt2 and avrB, extremely similar pathogen recognit...

  4. Soil water flow is a source of the plant pathogen Pseudomonas syringae in subalpine headwaters.

    OpenAIRE

    Monteil, Caroline; Lafolie, Francois; Laurent, Jimmy; Clement, Jean-Christophe; Simler, Roland; Travi, Yves

    2014-01-01

    The air-borne plant pathogenic bacterium Pseudomonas syringae is ubiquitous in headwaters, snowpack and precipitation where its populations are genetically and phenotypically diverse. Here, we assessed its population dynamics during snowmelt in headwaters of the French Alps. We revealed a continuous and significant transport of P. syringae by these waters in which the population density is correlated with water chemistry. Via in situ observations and laboratory experiments, we validated that ...

  5. Inhibitory activity of Iranian plant extracts on growth and biofilm formation by Pseudomonas aeruginosa

    OpenAIRE

    S Mansouri; Safa, A.; Najar, S. G.; Najar, A. G.

    2013-01-01

    Aims: Pseudomonas aeruginosa is a drug resistance opportunistic bacterium. Biofilm formation is key factor for survivalof P. aeruginosa in various environments. Polysaccharides may be involved in biofilm formation. The purpose of thisstudy was to evaluate antimicrobial and anti-biofilm activities of seven plant extracts with known alpha-glucosidaseinhibitory activities on different strains of P. aeruginosa.Methodology and results: Plants were extracted with methanol by the maceration method. ...

  6. Uptake and Active Efflux of Polycyclic Aromatic Hydrocarbons by Pseudomonas fluorescens LP6a

    OpenAIRE

    Bugg, Trevor; Foght, Julia M.; Pickard, Michael A.; Gray, Murray R.

    2000-01-01

    The mechanism of transport of polycyclic aromatic hydrocarbons (PAHs) by Pseudomonas fluorescens LP6a, a PAH-degrading bacterium, was studied by inhibiting membrane transport and measuring the resulting change in cellular uptake. Three cultures were used: wild-type LP6a which carried a plasmid for PAH degradation, a transposon mutant lacking the first enzyme in the pathway for PAH degradation, and a cured strain without the plasmid. Washed cells were mixed with aqueous solutions of radiolabel...

  7. A novel enterocin T1 with anti-Pseudomonas activity produced by Enterococcus faecium T1 from Chinese Tibet cheese.

    Science.gov (United States)

    Liu, Hui; Zhang, Lanwei; Yi, Huaxi; Han, Xue; Gao, Wei; Chi, Chunliang; Song, Wei; Li, Haiying; Liu, Chunguang

    2016-02-01

    An enterocin-producing Enterococcus faecium T1 was isolated from Chinese Tibet cheese. The enterocin was purified by SP-Sepharose and reversed phase HPLC. It was identified as unique from other reported bacteriocins based on molecular weight (4629 Da) and amino acid compositions; therefore it was subsequently named enterocin T1. Enterocin T1 was stable at 80-100 °C and over a wide pH range, pH 3.0-10.0. Protease sensitivity was observed to trypsin, pepsin, papain, proteinase K, and pronase E. Importantly, enterocin T1 was observed to inhibit the growth of numerous Gram-negative and Gram-positive bacteria including Pseudomonas putida, Pseudomonas aeruginosa, Pseudomonas fluorescens, Escherichia coli, Salmonella typhimurium, Shigella flexneri, Shigella sonnei, Staphylococcus aureus, Listeria monocytogenes. Take together, these results suggest that enterocin T1 is a novel bacteriocin with the potential to be used as a bio-preservative to control Pseudomonas spp. in food. PMID:26745981

  8. The algae-lytic ability of bacterium DC10 and the influence of environmental factors on the ability

    Institute of Scientific and Technical Information of China (English)

    SHI; Shunyu; LIU; Yongding; SHEN; Yinwu; LI; Genbao

    2005-01-01

    A lysing-bacterium DC10, isolated from Dianchi Lake of Yunnan Province, was characterized to be Pseudomonas sp. It was able to lyse some algae well, such as Microcystis viridis, Selenastrum capricornutum, and so on. In this study, it was shown that the bacterium lysed the algae by releasing a substance; the best lytic effects were achieved at Iow temperatures and in the dark. Different concentrations of CaCI2 and NaNO3 influenced the lytic effects;the ability to lyse algae decreased in the following order: pH 4 > pH 9 > pH 7 > pH 5.5. It was significant to develop a special technology with this kind of bacterium for controlling the bloomforming planktonic microalgae.

  9. Expression of phage-transposons of Pseudomonas aeruginosa in cells of Pseudomonas putida PpGl. II. Zygotic induction, an essential condition for the emergence of defective lysogens

    International Nuclear Information System (INIS)

    The presence of a large number of clones, which have lost the ability to produce phase, is a feature of PpGl exconjugants, which have acquired markers of the hybrid plasmid containing the genome of the PAO1 phage transposon. Analysis of these clones indicates that they contain plasmids with different defects in the phage genome (point mutations and different deletion lengths which may have an effect on both the phage genome and also plasmid RP4). Mutations of a particular region are selected, the region of early prophage genes. The process of zygotic induction is an essential condition for the arisal of mutants (including deletion mutants). The results of the experiment, which was based on the Luria-Delbruik test, showed that a significant proportion of the mutations, including deletion mutations, arise in the recipient cells PpGl

  10. Uptake of Hydrocarbon by Pseudomonas fluorescens (P1) and Pseudomonas putida (K1) Strains in the Presence of Surfactants: A Cell Surface Modification

    OpenAIRE

    Kaczorek, Ewa; Olszanowski, Andrzej

    2010-01-01

    The objective of this research was the evaluation of the effects of exogenous added surfactants on hydrocarbon biodegradation and on cell surface properties. Crude oil hydrocarbons are often difficult to remove from the environment because of their insolubility in water. The addition of surfactants enhances the removal of hydrocarbons by raising the solubility of these compounds. These surfactants cause them to become more vulnerable to degradation, thereby facilitating transportation across ...

  11. Isolation and evaluation of potent Pseudomonas species for bioremediation of phorate in amended soil.

    Science.gov (United States)

    Jariyal, Monu; Gupta, V K; Jindal, Vikas; Mandal, Kousik

    2015-12-01

    Use of phorate as a broad spectrum pesticide in agricultural crops is finding disfavor due to persistence of both the principal compound as well as its toxic residues in soil. Three phorate utilizing bacterial species (Pseudomonas sp. strain Imbl 4.3, Pseudomonas sp. strain Imbl 5.1, Pseudomonas sp. strain Imbl 5.2) were isolated from field soils. Comparative phorate degradation analysis of these species in liquid cultures identified Pseudomonas sp. strain Imbl 5.1 to cause complete metabolization of phorate during seven days as compared to the other two species in 13 days. In soils amended with phorate at different levels (100, 200, 300 mg kg(-1) soil), Pseudomonas sp. strain Imbl 5.1 resulted in active metabolization of phorate by between 94.66% and 95.62% establishing the same to be a potent bacterium for significantly relieving soil from phorate residues. Metabolization of phorate to these phorate residues did not follow the first order kinetics. This study proves that Pseudomonas sp. strain Imbl 5.1 has huge potential for active bioremediation of phorate both in liquid cultures and agricultural soils. PMID:26186726

  12. Partial purification and characterization of the organic solvent-tolerant lipase produced by Pseudomonas fluorescens RB02-3 isolated from milk.

    Science.gov (United States)

    Boran, Rukiye; Ugur, Aysel

    2010-01-01

    Eighty-five putative Pseudomonas isolates were obtained from various raw milk and pasteurized milk samples using Pseudomonas CFC agar. Among them, 36 isolates were identified as Pseudomonas fluorescens, and one isolate was identified as Pseudomonas putida. Lipase activity of the strains was quantitatively measured by the spectrophotometric method using p-nitrophenyl palmitate (p-NPP) as substrate. Detected lipase activity of the strains was between 10.03 U/mL and 22.16 U/mL. Pseudomonas fluorescens RB02-3 possessed the highest lipase activity. The extracellular lipase of P. fluorescens RB02-3 strain was homogeneously purified using a combination of ammonium sulfate precipitation, dialysis, and gel filtration column chromatography. This purification procedure resulted in 2.97-fold purification with 20.3% recovery. The enzyme was characterized, and exhibited maximum activity at pH 7.0 and 50 °C; after it was incubated for 1 h it was activated in the presence of hexane, ethyl acetate, isopropanol, and ethanol and remained stable after the incubation was extended for 2 hr. The lipase was slightly inhibited in the presence of Zn²+, Co²+, Cu²+, Ni²+ salts, and ethylenediamine tetraacetic acid (EDTA), whereas Cd²+, sodium dodecyl sulfate (SDS), and Tween-80 had no effect on its activity. PMID:21108127

  13. Saccharomyces cerevisiae genome-wide mutant screen for sensitivity to 2,4-diacetylphloroglucinol, a biocontrol antibiotic produced by Pseudomonas fluorescens

    Science.gov (United States)

    2,4-diacetylphloroglucinol (2,4-DAPG) is an antibiotic produced by Pseudomonas fluorescens that plays a key role in the ability of the bacterium to suppress phytopathogenic fungi. 2,4-DAPG has broad antibiotic activity, affecting organisms ranging from bacteria to higher plants. The biosynthesis and...

  14. Ex vivo transcriptional profiling reveals a common set of genes important for the adaptation of Pseudomonas aeruginosa to chronically infected host sites

    NARCIS (Netherlands)

    Bielecki, P.; Komor, U.; Bielecka, A.; Müsken, M.; Puchalka, J.; Pletz, M.W.; Ballmann, M.; Martins Dos Santos, V.A.P.; Weiss, S.; Häussler, S.

    2013-01-01

    The opportunistic bacterium Pseudomonas aeruginosa is a major nosocomial pathogen causing both devastating acute and chronic persistent infections. During the course of an infection, P.¿ aeruginosa rapidly adapts to the specific conditions within the host. In the present study, we aimed at the ident

  15. Bacterial tethering analysis reveals a "run-reverse-turn" mechanism for Pseudomonas species motility.

    Science.gov (United States)

    Qian, Chen; Wong, Chui Ching; Swarup, Sanjay; Chiam, Keng-Hwee

    2013-08-01

    We have developed a program that can accurately analyze the dynamic properties of tethered bacterial cells. The program works especially well with cells that tend to give rise to unstable rotations, such as polar-flagellated bacteria. The program has two novel components. The first dynamically adjusts the center of the cell's rotational trajectories. The second applies piecewise linear approximation to the accumulated rotation curve to reduce noise and separate the motion of bacteria into phases. Thus, it can separate counterclockwise (CCW) and clockwise (CW) rotations distinctly and measure rotational speed accurately. Using this program, we analyzed the properties of tethered Pseudomonas aeruginosa and Pseudomonas putida cells for the first time. We found that the Pseudomonas flagellar motor spends equal time in both CCW and CW phases and that it rotates with the same speed in both phases. In addition, we discovered that the cell body can remain stationary for short periods of time, leading to the existence of a third phase of the flagellar motor which we call "pause." In addition, P. aeruginosa cells adopt longer run lengths, fewer pause frequencies, and shorter pause durations as part of their chemotactic response. We propose that one purpose of the pause phase is to allow the cells to turn at a large angle, where we show that pause durations in free-swimming cells positively correlate with turn angle sizes. Taken together, our results suggest a new "run-reverse-turn" paradigm for polar-flagellated Pseudomonas motility that is different from the "run-and-tumble" paradigm established for peritrichous Escherichia coli. PMID:23728820

  16. Antivirulence activity of azithromycin in Pseudomonas aeruginosa

    Directory of Open Access Journals (Sweden)

    Francesco eImperi

    2014-04-01

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

  17. [Meningoencephalitis caused by Pseudomonas cepacia].

    Science.gov (United States)

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

    2006-01-01

    A case of meningoencephalitis of bacterial etiology caused by Pseudomonas cepacia was described. The strain was received at the Reference Laboratory of Bacterial Acute Respiratory Infections of "Pedro Kouri" Institute of Tropical Medicine, where its microbiological identification was confirmed. This isolation was a finding in an adult immunocompetent patient. The evolution was favourable with no sequelae for his future life. Pseudomona cepacia has been associated with respiratory infections in patients with cystic fibrosis. Patients with Pseudomonas cepacia may be asymptomatic or present fatal acute and fulminant infection. PMID:23427437

  18. Pseudomonas A1 influences the formation of hydroxyapatite and degrades bioglass

    International Nuclear Information System (INIS)

    Bacterial infections frequently lead to hard tissue destructions. The purpose of the present study was to address the question as to how the bacteria destroy hard tissues with the use of an in vitro system. A bacterium was isolated from a solution simulating body fluid which was identified as Pseudomonas A1, and is able to solubilize tricalcium phosphate when it grows in IP broth. The presence of Pseudomonas A1 resulted in dose-dependent inhibition of the formation of hydroxyapatite layer, on the surface of bioglass specimens immersed in SBF solution, in contrast to the control. When the bioglass specimens were immersed in IP broth without Ca3(PO4)2, so as to be present the appropriate inorganic ions for the survival of Pseudomonas but the only source of phosphate be derived from bioactive glass specimens, the formation of hydroxyapatite layer was not observed in any specimen. Additionally the presence of Pseudomonas resulted in 93.4% (w/w) and 85.9% (w/w) reduction on the surface composition of Ca and P, respectively, and further the rate of the decrease of specimen's weight was almost 50% higher in the presence of Pseudomonas compared with the control.

  19. Pseudomonas aeruginosa biofilm infections

    DEFF Research Database (Denmark)

    Tolker-Nielsen, Tim

    2014-01-01

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

  20. Plant growth-promoting effects of native Pseudomonas strains on Mentha piperita (peppermint): an in vitro study.

    Science.gov (United States)

    Santoro, M V; Cappellari, L R; Giordano, W; Banchio, E

    2015-11-01

    Plant growth-promoting rhizobacteria (PGPR) affect growth of host plants through various direct and indirect mechanisms. Three native PGPR (Pseudomonas putida) strains isolated from rhizospheric soil of a Mentha piperita (peppermint) crop field near Córdoba, Argentina, were characterised and screened in vitro for plant growth-promoting characteristics, such as indole-3-acetic acid (IAA) production, phosphate solubilisation and siderophore production, effects of direct inoculation on plant growth parameters (shoot fresh weight, root dry weight, leaf number, node number) and accumulation and composition of essential oils. Each of the three native strains was capable of phosphate solubilisation and IAA production. Only strain SJ04 produced siderophores. Plants directly inoculated with the native PGPR strains showed increased shoot fresh weight, glandular trichome number, ramification number and root dry weight in comparison with controls. The inoculated plants had increased essential oil yield (without alteration of essential oil composition) and biosynthesis of major essential oil components. Native strains of P. putida and other PGPR have clear potential as bio-inoculants for improving productivity of aromatic crop plants. There have been no comparative studies on the role of inoculation with native strains on plant growth and secondary metabolite production (specially monoterpenes). Native bacterial isolates are generally preferable for inoculation of crop plants because they are already adapted to the environment and have a competitive advantage over non-native strains. PMID:26012535