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Sample records for pseudomonas stutzeri an10

  1. Anaerobic oxidation of 2-chloroethanol under denitrifying conditions by Pseudomonas stutzeri strain JJ.

    Science.gov (United States)

    Dijk, J A; Stams, A J M; Schraa, G; Ballerstedt, H; de Bont, J A M; Gerritse, J

    2003-11-01

    A bacterium that uses 2-chloroethanol as sole energy and carbon source coupled to denitrification was isolated from 1,2-dichloroethane-contaminated soil. Its 16 S rDNA sequence showed 98% similarity with the type strain of Pseudomonas stutzeri (DSM 5190) and the isolate was tentatively identified as Pseudomonas stutzeri strain JJ. Strain JJ oxidized 2-chloroethanol completely to CO(2) with NO(3)(- )or O(2) as electron acceptor, with a preference for O(2) if supplied in combination. Optimum growth on 2-chloroethanol with nitrate occurred at 30 degrees C with a mu(max) of 0.14 h(-1) and a yield of 4.4 g protein per mol 2-chloroethanol metabolized. Under aerobic conditions, the mu(max) was 0.31 h(-1). NO(2)(-) also served as electron acceptor, but reduction of Fe(OH)(3), MnO(2), SO(4)(2-), fumarate or ClO(3)(-) was not observed. Another chlorinated compound used as sole energy and carbon source under aerobic and denitrifying conditions was chloroacetate. Various different bacterial strains, including some closely related Pseudomonas stutzeri strains, were tested for their ability to grow on 2-chloroethanol as sole energy and carbon source under aerobic and denitrifying conditions, respectively. Only three strains, Pseudomonas stutzeri strain LMD 76.42, Pseudomonas putida US2 and Xanthobacter autotrophicus GJ10, grew aerobically on 2-chloroethanol. This is the first report of oxidation of 2-chloroethanol under denitrifying conditions by a pure bacterial culture.

  2. Biotransformation of Tributyltin chloride by Pseudomonas stutzeri strain DN2

    Directory of Open Access Journals (Sweden)

    Dnyanada S. Khanolkar

    2014-12-01

    Full Text Available A bacterial isolate capable of utilizing tributyltin chloride (TBTCl as sole carbon source was isolated from estuarine sediments of west coast of India and identified as Pseudomonas stutzeri based on biochemical tests and Fatty acid methyl ester (FAME analysis. This isolate was designated as strain DN2. Although this bacterial isolate could resist up to 3 mM TBTCl level, it showed maximum growth at 2 mM TBTCl in mineral salt medium (MSM. Pseudomonas stutzeri DN2 exposed to 2 mM TBTCl revealed significant alteration in cell morphology as elongation and shrinkage in cell size along with roughness of cell surface. FTIR and NMR analysis of TBTCl degradation product extracted using chloroform and purified using column chromatography clearly revealed biotransformation of TBTCl into Dibutyltin dichloride (DBTCl2 through debutylation process. Therefore, Pseudomonas stutzeri strain DN2 may be used as a potential bacterial strain for bioremediation of TBTCl contaminated aquatic environmental sites.

  3. Biotransformation of Tributyltin chloride by Pseudomonas stutzeri strain DN2

    Science.gov (United States)

    Khanolkar, Dnyanada S.; Naik, Milind Mohan; Dubey, Santosh Kumar

    2014-01-01

    A bacterial isolate capable of utilizing tributyltin chloride (TBTCl) as sole carbon source was isolated from estuarine sediments of west coast of India and identified as Pseudomonas stutzeri based on biochemical tests and Fatty acid methyl ester (FAME) analysis. This isolate was designated as strain DN2. Although this bacterial isolate could resist up to 3 mM TBTCl level, it showed maximum growth at 2 mM TBTCl in mineral salt medium (MSM). Pseudomonas stutzeri DN2 exposed to 2 mM TBTCl revealed significant alteration in cell morphology as elongation and shrinkage in cell size along with roughness of cell surface. FTIR and NMR analysis of TBTCl degradation product extracted using chloroform and purified using column chromatography clearly revealed biotransformation of TBTCl into Dibutyltin dichloride (DBTCl2) through debutylation process. Therefore, Pseudomonas stutzeri strain DN2 may be used as a potential bacterial strain for bioremediation of TBTCl contaminated aquatic environmental sites. PMID:25763027

  4. Chitinase activity of Pseudomonas stutzeri PT5 in different fermentation condition

    Science.gov (United States)

    Chalidah, N.; Khotimah, I. N.; Hakim, A. R.; Meata, B. A.; Puspita, I. D.; Nugraheni, P. S.; Ustadi; Pudjiraharti, S.

    2018-03-01

    This study aimed to determine the incubation condition of Pseudomonas stutzeri PT5 in producing chitin degrading enzyme in various pH and temperatures; to compare the production of chitin degrading enzyme in chitin medium supplemented with additional nitrogen, carbon and a mixture of nitrogen and carbon sources and to observe the production of chitin degrading enzyme in 250 mL-shake flasks and 2 L-fermentor. The parameters tested during production were chitinase activity (U·mL-1) of culture supernatant and N-acetylglucosamine concentration (μg·mL-1) in the medium. The results showed that Pseudomonas stutzeri PT5 was able to produce the highest chitinase activity at pH 6 and temperature of 37 °C (0.024 U·mL-1). The addition of 0.1 % of ammonium phosphate and 0.1 % of maltose, increased the chitinase activity of Pseudomonas stutzeri PT5 by 3.24 and 8.08 folds, respectively, compared to the control. The addition of 0.1 % ammonium phosphate and 0.1 % maltose mixture to chitin medium resulted in the shorter time of chitinase production compared to the addition of sole nutrition. The production of chitinase using 2 L-fermentor shows that the highest chitinase activity produced by Pseudomonas stutzeri PT5 was reached at 1-day incubation (0.0283 U·mL-1), which was shorter than in 250 mL-shake flasks.

  5. Prosthetic vascular graft infection and prosthetic joint infection caused by Pseudomonas stutzeri.

    Science.gov (United States)

    Bonares, Michael J; Vaisman, Alon; Sharkawy, Abdu

    2016-01-01

    Pseudomonas stutzeri is infrequently isolated from clinical specimens, and if isolated, more likely represents colonization or contamination rather than infection. Despite this, there are dozens of case reports which describe clinically significant P. stutzeri infections at variable sites. A 69-year-old man had a P. stutzeri infection of a prosthetic vascular graft infection, which he received in Panama City. He was successfully treated with a single antipseudomonal agent for 6 weeks and the removal of the infected vascular graft. A 70-year-old man had a P. stutzeri infection of a prosthetic joint, which was successfully treated with a single anti-pseudomonal agent for 6 weeks. There is only one other documented case of a prosthetic vascular graft infection secondary to P. stutzeri . There are 5 documented cases of P. stutzeri prosthetic joint infections. The previous cases were treated with antibiotics and variably, source control with the removal of prosthetic material. Most cases of P. stutzeri infection are due to exposure in health care settings. Immunocompromised states such as HIV or hematological and solid tumor malignancies are risk factors for P. stutzeri infection. Infections caused by P. stutzeri are far less frequent and less fatal than those caused by P. aeruginosa. The etiology of a P. stutzeri infection could be exposure to soil and water, but also contaminated material in the health care setting or an immunocompromised state. Iatrogenic infections that are secondary to health care tourism are a potential cause of fever in the returned traveler.

  6. 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...

  7. Degradation of soil cyanide by single and mixed cultures of Pseudomonas stutzeri and Bacillus subtilis.

    Science.gov (United States)

    Nwokoro, Ogbonnaya; Dibua, Marie Esther Uju

    2014-03-01

    The aim of this investigation was to study whether certain bacteria could be used for cyanide degradation in soil. The bacteria Pseudomonas stutzeri and Bacillus subtilis were selected based on their good growth in a minimal medium containing 0.8 mg mL-1 potassium cyanide (KCN). In this study we tested their ability to reduce cyanide levels in a medium containing 1.5 mg mL-1 of KCN. Although both microorganisms reduced cyanide levels, Pseudomonas stutzeri was the more effective test organism. Later on, the selected cultures were grown, diluted and their various cell concentrations were used individually and in combination to test their ability of cyanide degradation in soil samples collected around a cassava processing mill. Bacillus subtilis caused degradation of soil cyanide from 0.218 mg g-1 soil immediately with an inoculum concentration of 0.1 (OD600nm) to 0.072 mg g-1 soil after 10 days with an inoculum concentration of 0.6 (OD600nm) implying a 66.9 % reduction. Pseudomonas stutzeri cell concentration of 0.1 (OD600nm) decreased soil cyanide from 0.218 mg g-1 soil initially to 0.061 mg g-1 soil after 10 days with an inoculum concentration of 0.6 (OD600nm) (72 % reduction). The mixed culture of the two bacteria produced the best degradation of soil cyanide from 0.218 mg g-1 soil sample with a combined inoculum concentration of 0.1 (OD600nm) initially to 0.025 mg g-1 soil with a combined inoculum concentration of 0.6 (OD600nm) after 10 days incubation resulting in an 88.5 % degradation of soil cyanide. The analysed bacteria displayed high cyanide degradation potential and may be useful for efficient decontamination of cyanide contaminated sites.

  8. Anaerobic degradation of long-chain alkylamines by a denitrifying Pseudomonas stutzeri

    NARCIS (Netherlands)

    Nguyen, P.D.; Ginkel, van C.G.; Plugge, C.M.

    2008-01-01

    The anaerobic degradation of tetradecylamine and other long-chain alkylamines by a newly isolated denitrifying bacterium was studied. Strain ZN6 was isolated from a mixture of soil and active sludge and was identified as representing Pseudomonas stutzeri, based on partial 16S rRNA gene sequence

  9. Engineering Pseudomonas stutzeri as a biogeochemical biosensor

    Science.gov (United States)

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

    2016-12-01

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

  10. KINETIC DISTRIBUTION MODEL OF EVAPORATION, BIOSORPTION AND BIODEGRADATION OF POLYCHLORINATED BIPHENYLS (PCBS) IN THE SUSPENSION OF PSEUDOMONAS STUTZERI. (R826652)

    Science.gov (United States)

    AbstractKinetics of distribution of PCBs in an active bacterial suspension of Pseudomonas stutzeri was studied by monitoring the evaporated amounts and the concentration remaining in the liquid medium with the biomass. To determine the biodegradation rate const...

  11. Biosurfactant and enzyme mediated crude oil degradation by Pseudomonas stutzeri NA3 and Acinetobacter baumannii MN3.

    Science.gov (United States)

    Parthipan, Punniyakotti; Elumalai, Punniyakotti; Sathishkumar, Kuppusamy; Sabarinathan, Devaraj; Murugan, Kadarkarai; Benelli, Giovanni; Rajasekar, Aruliah

    2017-10-01

    The present study focuses on the optimization of biosurfactant (BS) production using two potential biosurfactant producer Pseudomonas stutzeri NA3 and Acinetobacter baumannii MN3 and role of enzymes in the biodegradation of crude oil. The optimal conditions for P. stutzeri NA3 and A. baumannii MN3 for biodegradation were pH of 8 and 7; temperature of 30 and 40 °C, respectively. P. stutzeri NA3 and A. baumannii MN3 produced 3.81 and 4.68 g/L of BS, respectively. Gas chromatography mass spectrometry confirmed that BS was mainly composed of fatty acids. Furthermore, the role of the degradative enzymes, alkane hydroxylase, alcohol dehydrogenase and laccase on biodegradation of crude oil are explained. Maximum biodegradation efficiency (BE) was recorded for mixed consortia (86%) followed by strain P. stutzeri NA3 (84%). Both bacterial strains were found to be vigorous biodegraders of crude oil than other biosurfactant-producing bacteria due to their enzyme production capabilities and our results suggests that the bacterial isolates can be used for effective degradation of crude oil within short time periods.

  12. Crystallization and preliminary X-ray diffraction studies of l-rhamnose isomerase from Pseudomonas stutzeri

    International Nuclear Information System (INIS)

    Yoshida, Hiromi; Wayoon, Poonperm; Takada, Goro; Izumori, Ken; Kamitori, Shigehiro

    2006-01-01

    Recombinant l-rhamnose isomerase from P. stutzeri has been crystallized. Diffraction data have been collected to 2.0 Å resolution. l-Rhamnose isomerase from Pseudomonas stutzeri (P. stutzeril-RhI) catalyzes not only the reversible isomerization of l-rhamnose to l-rhamnulose, but also isomerization between various rare aldoses and ketoses. Purified His-tagged P. stutzeril-RhI was crystallized by the hanging-drop vapour-diffusion method. The crystals belong to the monoclinic space group P2 1 , with unit-cell parameters a = 74.3, b = 104.0, c = 107.0 Å, β = 106.8°. Diffraction data have been collected to 2.0 Å resolution. The molecular weight of the purified P. stutzeril-RhI with a His tag at the C-terminus was confirmed to be 47.7 kDa by MALDI–TOF mass-spectrometric analysis and the asymmetric unit is expected to contain four molecules

  13. Optimization of exopolysaccharide production from Pseudomonas stutzeri AS22 and examination of its metal-binding abilities.

    Science.gov (United States)

    Maalej, H; Hmidet, N; Boisset, C; Buon, L; Heyraud, A; Nasri, M

    2015-02-01

    To investigate the effect of culture conditions and medium components on exopolysaccharide (EPS) production by Pseudomonas stutzeri AS22 and to access the EPS performance as a metal-binding exopolysaccharide. The EPS production conditions of Ps. stutzeri AS22 in submerged culture were optimized using two approaches for EPS quantification, and its metal-binding capacity was evaluated using both single and mixed metal ions systems. Maximum EPS level was achieved after 24 h of incubation at 30°C with an initial pH of 8.0, 250 rev min(-1) stirring level and 10% inoculum size. 50 g l(-1) starch, 5 g l(-1) yeast extract, 0.5 g l(-1) NaCl, 1.4 g l(-1) K2 HPO4, 0.4 g l(-1) MgSO4, 0.4 g l(-1) CaCl2 and 1 g l(-1) mannose were found to be the most suitable carbon, nitrogen, mineral and additional carbohydrate sources, respectively. From metal-binding experiments, the crude EPS showed interesting metal adsorption capacity adopting the order Pb > Co > Fe > Cu > Cd. Lead was preferentially biosorbed with a maximal uptake of 460 mg g(-1) crude EPS. Under the optimal culture requirements, EPS level reached 10.2 g l(-1) after 24 h of fermentation, seven times more than the production under initial conditions. According to the metal-binding assay, the crude EPS has potential to be used as a novel biosorbent in the treatment of heavy metals-contaminated water. Our results are interesting in terms of yield as well as efficiency for the potential use of the Ps. stutzeri exopolysaccharide as a metal-absorbent polymer in the bioremediation field. © 2014 The Society for Applied Microbiology.

  14. Crystallization of purple nitrous oxide reductase from Pseudomonas stutzeri

    International Nuclear Information System (INIS)

    Pomowski, Anja; Zumft, Walter G.; Kroneck, Peter M. H.; Einsle, Oliver

    2010-01-01

    The physiologically active form of nitrous oxide reductase was isolated and crystallized under strict exclusion of dioxygen and diffraction data were collected from crystals belonging to two different space groups. Nitrous oxide reductase (N 2 OR) from Pseudomonas stutzeri catalyzes the final step in denitrification: the two-electron reduction of nitrous oxide to molecular dinitrogen. Crystals of the enzyme were grown under strict exclusion of dioxygen by sitting-drop vapour diffusion using 2R,3R-butanediol as a cryoprotectant. N 2 OR crystallized in either space group P1 or P6 5 . Interestingly, the key determinant for the resulting space group was the crystallization temperature. Crystals belonging to space group P1 contained four 130 kDa dimers in the asymmetric unit, while crystals belonging to space group P6 5 contained a single dimer in the asymmetric unit. Diffraction data were collected to resolutions better than 2 Å

  15. Coal induced production of a rhamnolipid biosurfactant by Pseudomonas stutzeri, isolated from the formation water of Jharia coalbed.

    Science.gov (United States)

    Singh, Durgesh Narain; Tripathi, Anil Kumar

    2013-01-01

    A strain of Pseudomonas stutzeri was isolated form an enrichment of perchlorate reducing bacteria from the formation water collected from an Indian coalbed which solubilized coal and produced copious amount of biosurfactant when coal was added to the medium. It produced maximum biosurfactant with lignite coal followed by olive oil and soybean oil which was able to emulsify several aromatic hydrocarbons including kerosene oil, diesel oil, hexane, toluene etc. Haemolytic test, growth inhibition of Bacillus subtilis and FTIR analysis showed rhamnolipid nature of the biosurfactant. The stability of the coal induced biosurfactant in pH range of 4-8 and up to 25% NaCl concentration and 100 °C temperature suggests that due to its ability to produce biosurfactant and solubilize coal P. stutzeri may be useful in the coalbed for in situ biotransformation of coal into methane and in the bioremediation of PAHs from oil contaminated sites including marine environments. Copyright © 2012 Elsevier Ltd. All rights reserved.

  16. Production of rhamnolipids by Pseudomonas aeruginosa is inhibited by H2S but resumes in a co-culture with P. stutzeri: applications for microbial enhanced oil recovery.

    Science.gov (United States)

    Zhao, Feng; Ma, Fang; Shi, Rongjiu; Zhang, Jie; Han, Siqin; Zhang, Ying

    2015-09-01

    Sulfate-reducing bacteria and H2S exist widely in oil production systems, and in situ production of rhamnolipids is promising for microbial enhanced oil recovery (MEOR). However, information of the effect of S(2-) on rhamnolipids production is scarce. Two facultative anaerobic rhamnolipids-producing bacterial strains, Pseudomonas aeruginosa SG and WJ-1, were used. Above 10 mg S(2-)/l, both cell growth and rhamnolipids production were inhibited. A large inoculum (9%, v/v) failed to completely relieve the inhibitory effect of 10 mg S(2-)/l. Below 30 mg S(2-)/l, both strains resumed rhamnolipid production through co-culturing with the denitrifying and sulphide-removing strain Pseudomonas stutzeri DQ1. H2S has a direct but reversible inhibitory effect on rhamnolipids production. Control of H2S in oilfields is indispensable to MEOR, and the co-culture method is effective in restoring rhamnolipid production in presence of S(2-).

  17. Sequential unfolding of the two-domain protein Pseudomonas stutzeri cytochrome c(4)

    DEFF Research Database (Denmark)

    Andersen, Niels Højmark; Jensen, Thomas Jon; Nørgaard, Allan

    2002-01-01

    F stutzeri cytochrome c. is a di-haem protein, composed of two globular domains each with His-Met coordinated haem. and a hydrogen bond network between the domains. The domain foldings are highly symmetric but with specific differences including structural differences of ligand coordination, and ...

  18. The impact of siderophore secretion by pseudomonas stutzeri to chelating cu metal in solution culture

    International Nuclear Information System (INIS)

    Azmat, R.

    2014-01-01

    This article discuss the interaction of siderophores (which are low molecular weight, secreted metabolites) of microorganisms (Pseudomonas stutzeri) separately and simultaneously with Cu metal in the solution culture on the roots of 4d old seedlings of Vigna radiata. Naturally occurring bacteria play an important role in plant growth due to the release of pigment. It is a coloring compound (siderophore) showed high chemical oxygen demand (COD), lowers the pressure of oxygen. This lowers the nutrient uptake by the roots due to which reduced plant growth with metabolic disorder was observed in the whole plant. A wide range of phenomena from simple to complex interactions was observed between microorganisms and Cu metal in relation with plant root growth such as adsorption, oxidation/reduction of pigment, solubilization. Results showed that microbial strain showed a significant effect on weight of root in aqueous culture whereas nutrient medium support the root growth. Biochemical analysis reflects that lipids were main target of both abiotic and biotic stress that may utilizes to overcome the stress due to which protein contents were seemed to be unaffected at highest concentration of metal or it may also be related with the degradation of lipids due to the biotic and abiotic stress. (author)

  19. Structural, functional, and evolutionary analysis of moeZ, a gene encoding an enzyme required for the synthesis of the Pseudomonas metabolite, pyridine-2,6-bis(thiocarboxylic acid

    Directory of Open Access Journals (Sweden)

    Crawford Ronald L

    2002-04-01

    Full Text Available Abstract Background Pyridine-2,6-bis(thiocarboxylic acid (pdtc is a small secreted metabolite that has a high affinity for transition metals, increases iron uptake efficiency by 20% in Pseudomonas stutzeri, has the ability to reduce both soluble and mineral forms of iron, and has antimicrobial activity towards several species of bacteria. Six GenBank sequences code for proteins similar in structure to MoeZ, a P. stutzeri protein necessary for the synthesis of pdtc. Results Analysis of sequences similar to P. stutzeri MoeZ revealed that it is a member of a superfamily consisting of related but structurally distinct proteins that are members of pathways involved in the transfer of sulfur-containing moieties to metabolites. Members of this family of enzymes are referred to here as MoeB, MoeBR, MoeZ, and MoeZdR. MoeB, the molybdopterin synthase activating enzyme in the molybdopterin cofactor biosynthesis pathway, is the most characterized protein from this family. Remarkably, lengths of greater than 73% nucleic acid homology ranging from 35 to 486 bp exist between Pseudomonas stutzeri moeZ and genomic sequences found in some Mycobacterium, Mesorhizobium, Pseudomonas, Streptomyces, and cyanobacteria species. Conclusions The phylogenetic relationship among moeZ sequences suggests that P. stutzeri may have acquired moeZ through lateral gene transfer from a donor more closely related to mycobacteria and cyanobacteria than to proteobacteria. The importance of this relationship lies in the fact that pdtc, the product of the P. stutzeri pathway that includes moeZ, has an impressive set of capabilities, some of which could make it a potent pathogenicity factor.

  20. Novel heterotrophic nitrogen removal and assimilation characteristic of the newly isolated bacterium Pseudomonas stutzeri AD-1.

    Science.gov (United States)

    Qing, Hui; Donde, Oscar Omondi; Tian, Cuicui; Wang, Chunbo; Wu, Xingqiang; Feng, Shanshan; Liu, Yao; Xiao, Bangding

    2018-04-18

    AD-1, an aerobic denitrifier, was isolated from activated sludge and identified as Pseudomonas stutzeri. AD-1 completely removed NO 3 - or NO 2 - and removed 99.5% of NH 4 + during individual culturing in a broth medium with an initial nitrogen concentration of approximately 50 mg L -1 . Results showed that larger amounts of nitrogen were removed through assimilation by the bacteria. And when NH 4 + was used as the sole nitrogen source in the culture medium, neither NO 2 - nor NO 3 - was detected, thus indicating that AD-1 may not be a heterotrophic nitrifier. Only trace amount of N 2 O was detected during the denitrification process. Single factor experiments indicated that the optimal culture conditions for AD-1 were: a carbon-nitrogen ratio (C/N) of 15, a temperature of 25°C and sodium succinate or glucose as a carbon source. In conclusion, due to the ability of AD-1 to utilize nitrogen of different forms with high efficiencies for its growth while producing only trace emissions of N 2 O, the bacterium had outstanding potential to use in the bioremediation of high-nitrogen-containing wastewaters. Meanwhile, it may also be a proper candidate for biotreatment of high concentration organic wastewater. Copyright © 2018 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  1. Biosurfactants produced by Bacillus subtilis A1 and Pseudomonas stutzeri NA3 reduce longevity and fecundity of Anopheles stephensi and show high toxicity against young instars.

    Science.gov (United States)

    Parthipan, Punniyakotti; Sarankumar, Raja Kumaresan; Jaganathan, Anitha; Amuthavalli, Pandian; Babujanarthanam, Ranganathan; Rahman, Pattanathu K S M; Murugan, Kadarkarai; Higuchi, Akon; Benelli, Giovanni; Rajasekar, Aruliah

    2018-04-01

    Anopheles stephensi acts as vector of Plasmodium parasites, which are responsible for malaria in tropical and subtropical areas worldwide. Currently, malaria management is a big challenge due to the presence of insecticide-resistant strains as well as to the development of Plasmodium species highly resistant to major antimalarial drugs. Therefore, the present study focused on biosurfactant produced by two bacteria Bacillus subtilis A1 and Pseudomonas stutzeri NA3, evaluating them for insecticidal applications against malaria mosquitoes. The produced biosurfactants were characterized using FT-IR spectroscopy and gas chromatography-mass spectrometry (GC-MS), which confirmed that biosurfactants had a lipopeptidic nature. Both biosurfactants were tested against larvae and pupae of A. stephensi. LC 50 values were 3.58 (larva I), 4.92 (II), 5.73 (III), 7.10 (IV), and 7.99 (pupae) and 2.61 (I), 3.68 (II), 4.48 (III), 5.55 (IV), and 6.99 (pupa) for biosurfactants produced by B. subtilis A1 and P. stutzeri NA3, respectively. Treatments with bacterial surfactants led to various physiological changes including longer pupal duration, shorter adult oviposition period, and reduced longevity and fecundity. To the best of our knowledge, there are really limited reports on the mosquitocidal and physiological effects due to biosurfactant produced by bacterial strains. Overall, the toxic activity of these biosurfactant on all young instars of A. stephensi, as well as their major impact on adult longevity and fecundity, allows their further consideration for the development of insecticides in the fight against malaria mosquitoes.

  2. Simultaneous inhibition of sulfate-reducing bacteria, removal of H2S and production of rhamnolipid by recombinant Pseudomonas stutzeri Rhl: Applications for microbial enhanced oil recovery.

    Science.gov (United States)

    Zhao, Feng; Zhou, Ji-Dong; Ma, Fang; Shi, Rong-Jiu; Han, Si-Qin; Zhang, Jie; Zhang, Ying

    2016-05-01

    Sulfate-reducing bacteria (SRB) are widely existed in oil production system, and its H2S product inhibits rhamnolipid producing bacteria. In-situ production of rhamnolipid is promising for microbial enhanced oil recovery. Inhibition of SRB, removal of H2S and production of rhamnolipid by recombinant Pseudomonas stutzeri Rhl were investigated. Strain Rhl can simultaneously remove S(2-) (>92%) and produce rhamnolipid (>136mg/l) under S(2-) stress below 33.3mg/l. Rhl reduced the SRB numbers from 10(9) to 10(5)cells/ml, and the production of H2S was delayed and decreased to below 2mg/l. Rhl also produced rhamnolipid and removed S(2-) under laboratory simulated oil reservoir conditions. High-throughput sequencing data demonstrated that addition of strain Rhl significantly changed the original microbial communities of oilfield production water and decreased the species and abundance of SRB. Bioaugmentation of strain Rhl in oilfield is promising for simultaneous control of SRB, removal of S(2-) and enhance oil recovery. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Optimization of culture medium for anaerobic production of rhamnolipid by recombinant Pseudomonas stutzeri Rhl for microbial enhanced oil recovery.

    Science.gov (United States)

    Zhao, F; Mandlaa, M; Hao, J; Liang, X; Shi, R; Han, S; Zhang, Y

    2014-08-01

    Response surface methodology was employed to enhance the anaerobic production of rhamnolipid by recombinant Pseudomonas stutzeri Rhl. Glycerol is a promising carbon source used to anaerobically produce rhamnolipid. In a Plackett-Burman design, glycerol, KH2 PO4 and yeast extract were significant factors. The proposed optimized medium contained the following: 46·55 g l(-1) glycerol; 3 g l(-1) NaNO3 ; 5·25 g l(-1) K2 HPO4 ·3H2 O; 5·71 g l(-1) KH2 PO4 ; 0·40 g l(-1) MgSO4 ·7H2 O; 0·13 g l(-1) CaCl2 ; 1·0 g l(-1) KCl; 1·0 g l(-1) NaCl; and 2·69 g l(-1) yeast extract. Using this optimized medium, we obtained an anaerobic yield of rhamnolipid of 3·12 ± 0·11 g l(-1) with a 0·85-fold increase. Core flooding test results also revealed that Ps. stutzeri Rhl grown in an optimized medium enhanced the oil recovery efficiency by 15·7%, which was 6·6% higher than in the initial medium. Results suggested that the optimized medium is a promising nutrient source that could effectively mobilize oil by enhancing the in situ production of rhamnolipid. The ex situ application of rhamnolipid for microbial enhanced oil recovery (MEOR) is costly and complex in terms of rhamnolipid production, purification and transportation. Compared with ex situ applications, the in situ production of rhamnolipid in anaerobic oil reservoir is more advantageous for MEOR. This study is the first to report the anaerobic production optimization of rhamnolipid. Results showed that the optimized medium enhanced not only the anaerobic production of rhamnolipid but also crude oil recovery. © 2014 The Society for Applied Microbiology.

  4. Global transcriptional analysis of nitrogen fixation and ammonium repression in root-associated Pseudomonas stutzeri A1501

    Directory of Open Access Journals (Sweden)

    Lu Wei

    2010-01-01

    Full Text Available Abstract Background Biological nitrogen fixation is highly controlled at the transcriptional level by regulatory networks that respond to the availability of fixed nitrogen. In many diazotrophs, addition of excess ammonium in the growth medium results in immediate repression of nif gene transcription. Although the regulatory cascades that control the transcription of the nif genes in proteobacteria have been well investigated, there are limited data on the kinetics of ammonium-dependent repression of nitrogen fixation. Results Here we report a global transcriptional profiling analysis of nitrogen fixation and ammonium repression in Pseudomonas stutzeri A1501, a root-associated and nitrogen-fixing bacterium. A total of 166 genes, including those coding for the global nitrogen regulation (Ntr and Nif-specific regulatory proteins, were upregulated under nitrogen fixation conditions but rapidly downregulated as early as 10 min after ammonium shock. Among these nitrogen fixation-inducible genes, 95 have orthologs in each of Azoarcus sp. BH72 and Azotobacter vinelandii AvoP. In particular, a 49-kb expression island containing nif and other associated genes was markedly downregulated by ammonium shock. Further functional characterization of pnfA, a new NifA-σ54-dependent gene chromosomally linked to nifHDK, is reported. This gene encodes a protein product with an amino acid sequence similar to that of five hypothetical proteins found only in diazotrophic strains. No noticeable differences in the transcription of nifHDK were detected between the wild type strain and pnfA mutant. However, the mutant strain exhibited a significant decrease in nitrogenase activity under microaerobic conditions and lost its ability to use nitrate as a terminal electron acceptor for the support of nitrogen fixation under anaerobic conditions. Conclusions Based on our results, we conclude that transcriptional regulation of nif gene expression in A1501 is mediated by the nif

  5. Evolutionary Plasticity of AmrZ Regulation in Pseudomonas

    Science.gov (United States)

    Dougherty, Kevin; Diaz, Beatriz; Murillo, Rachel

    2018-01-01

    ABSTRACT amrZ encodes a master regulator protein conserved across pseudomonads, which can be either a positive or negative regulator of swimming motility depending on the species examined. To better understand plasticity in the regulatory function of AmrZ, we characterized the mode of regulation for this protein for two different motility-related phenotypes in Pseudomonas stutzeri. As in Pseudomonas syringae, AmrZ functions as a positive regulator of swimming motility within P. stutzeri, which suggests that the functions of this protein with regard to swimming motility have switched at least twice across pseudomonads. Shifts in mode of regulation cannot be explained by changes in AmrZ sequence alone. We further show that AmrZ acts as a positive regulator of colony spreading within this strain and that this regulation is at least partially independent of swimming motility. Closer investigation of mechanistic shifts in dual-function regulators like AmrZ could provide unique insights into how transcriptional pathways are rewired between closely related species. IMPORTANCE Microbes often display finely tuned patterns of gene regulation across different environments, with major regulatory changes controlled by a small group of “master” regulators within each cell. AmrZ is a master regulator of gene expression across pseudomonads and can be either a positive or negative regulator for a variety of pathways depending on the strain and genomic context. Here, we demonstrate that the phenotypic outcomes of regulation of swimming motility by AmrZ have switched at least twice independently in pseudomonads, so that AmrZ promotes increased swimming motility in P. stutzeri and P. syringae but represses this phenotype in Pseudomonas fluorescens and Pseudomonas aeruginosa. Since examples of switches in regulatory mode are relatively rare, further investigation into the mechanisms underlying shifts in regulator function for AmrZ could provide unique insights into the

  6. Secretion of human epidermal growth factor (EGF) in autotrophic culture by a recombinant hydrogen-utilizing bacterium, Pseudomonas pseudoflava, carrying broad-host-range EGF secretion vector pKSEGF2.

    OpenAIRE

    Hayase, N; Ishiyama, A; Niwano, M

    1994-01-01

    We constructed the broad-host-range human epidermal growth factor (EGF) secretion plasmid pKSEGF2 by inserting the Escherichia coli tac promoter, the signal sequence of Pseudomonas stutzeri amylase, and the synthesized EGF gene into the broad-host-range vector pKT230. E. coli JM109 carrying pKSEGF2 secreted EGF into the periplasm and the culture medium under the control of the tac promoter. Pseudomonas aeruginosa PAO1161 carrying pKSEGF2 and Pseudomonas putida AC10 carrying pKSEGF2 secreted E...

  7. 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

  8. Heterologous production of Pseudomonas aeruginosa rhamnolipid under anaerobic conditions for microbial enhanced oil recovery.

    Science.gov (United States)

    Zhao, F; Shi, R; Zhao, J; Li, G; Bai, X; Han, S; Zhang, Y

    2015-02-01

    The ex situ application of rhamnolipid to enhance oil recovery is costly and complex in terms of rhamnolipid production and transportation, while in situ production of rhamnolipid is restricted by the oxygen-deficient environments of oil reservoirs. To overcome the oxygen-limiting conditions and to circumvent the complex regulation of rhamnolipid biosynthesis in Pseudomonas aeruginosa, an engineered strain Pseudomonas stutzeri Rhl was constructed for heterologous production of rhamnolipid under anaerobic conditions. The rhlABRI genes for rhamnolipid biosynthesis were cloned into a facultative anaerobic strain Ps. stutzeri DQ1 to construct the engineered strain Rhl. Anaerobic production of rhamnolipid was confirmed by thin layer chromatography and Fourier transform infrared analysis. Rhamnolipid product reduced the air-water surface tension to 30.3 mN m(-1) and the oil-water interfacial tension to 0.169 mN m(-1). Rhl produced rhamnolipid of 1.61 g l(-1) using glycerol as the carbon source. Rhl anaerobic culture emulsified crude oil up to EI24 ≈ 74. An extra 9.8% of original crude oil was displaced by Rhl in the core flooding test. Strain Rhl achieved anaerobic production of rhamnolipid and worked well for enhanced oil recovery in the core flooding model. The rhamnolipid produced by Rhl was similar to that of the donor strain SQ6. This is the first study to achieve anaerobic and heterologous production of rhamnolipid. Results demonstrated the potential feasibility of Rhl as a promising strain to enhance oil recovery through anaerobic production of rhamnolipid. © 2014 The Society for Applied Microbiology.

  9. NCBI nr-aa BLAST: CBRC-XTRO-01-0090 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-XTRO-01-0090 ref|YP_001173131.1| DNA internalization-related competence protei...n ComEC/Rec2 [Pseudomonas stutzeri A1501] gb|ABP80289.1| DNA internalization-related competence protein ComEC/Rec2 [Pseudomonas stutzeri A1501] YP_001173131.1 0.096 28% ...

  10. NCBI nr-aa BLAST: CBRC-XTRO-01-3405 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-XTRO-01-3405 ref|YP_001173131.1| DNA internalization-related competence protei...n ComEC/Rec2 [Pseudomonas stutzeri A1501] gb|ABP80289.1| DNA internalization-related competence protein ComEC/Rec2 [Pseudomonas stutzeri A1501] YP_001173131.1 0.016 29% ...

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

    Science.gov (United States)

    2013-01-01

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

  12. Mass spectrometry identification of alkyl-substituted pyrazines produced by Pseudomonas spp. isolates obtained from wine corks.

    Science.gov (United States)

    Bañeras, Lluís; Trias, Rosalia; Godayol, Anna; Cerdán, Laura; Nawrath, Thorben; Schulz, Stefan; Anticó, Enriqueta

    2013-06-15

    We investigated the pyrazine production of 23 Pseudomonas isolates obtained from cork in order to assess their implications in off-flavour development. Off-flavour development in cork stoppers is a crucial process in maintaining the high quality of some wines. Pyrazine production was analyzed by headspace solid-phase-microextraction (HS-SPME) and gas chromatography coupled with mass spectrometry (GC-MS). Five out of the 23 isolates, i.e. Pseudomonas koreensis TCA20, Pseudomonas palleroniana TCA16, Pseudomonas putida TCA23 and N7, and Pseudomonas stutzeri TRA27a were able to produce branched alkyl-substituted pyrazines. For isolates N7 and TCA16, 14 compounds could be identified as pyrazines. The use of mineral media supplemented with different carbon and nitrogen sources resulted in changes in the pyrazine production capacity. In the two strains the amount of pyrazines produced was higher with glucose and decreased significantly with lactate. In all cases, 2,5-di(1-methylethyl)pyrazine was found to be dominant and independent of amino acid addition, suggesting a completely de novo synthesis. Aroma descriptions of most alkyl substituted pyrazines include mild vegetal aromas, not necessarily undesirable for the cork manufacturing industry. Methoxypyrazines, exhibiting earthy and musty aromas, could not be detected in any of the strains analysed. Copyright © 2012 Elsevier Ltd. All rights reserved.

  13. Strategy of Pseudomonas pseudoalcaligenes C70 for effective degradation of phenol and salicylate.

    Directory of Open Access Journals (Sweden)

    Merike Jõesaar

    Full Text Available Phenol- and naphthalene-degrading indigenous Pseudomonas pseudoalcaligenes strain C70 has great potential for the bioremediation of polluted areas. It harbours two chromosomally located catechol meta pathways, one of which is structurally and phylogenetically very similar to the Pseudomonas sp. CF600 dmp operon and the other to the P. stutzeri AN10 nah lower operon. The key enzymes of the catechol meta pathway, catechol 2,3-dioxygenase (C23O from strain C70, PheB and NahH, have an amino acid identity of 85%. The metabolic and regulatory phenotypes of the wild-type and the mutant strain C70ΔpheB lacking pheB were evaluated. qRT-PCR data showed that in C70, the expression of pheB- and nahH-encoded C23O was induced by phenol and salicylate, respectively. We demonstrate that strain C70 is more effective in the degradation of phenol and salicylate, especially at higher substrate concentrations, when these compounds are present as a mixture; i.e., when both pathways are expressed. Moreover, NahH is able to substitute for the deleted PheB in phenol degradation when salicylate is also present in the growth medium. The appearance of a yellow intermediate 2-hydroxymuconic semialdehyde was followed by the accumulation of catechol in salicylate-containing growth medium, and lower expression levels and specific activities of the C23O of the sal operon were detected. However, the excretion of the toxic intermediate catechol to the growth medium was avoided when the growth medium was supplemented with phenol, seemingly due to the contribution of the second meta pathway encoded by the phe genes.

  14. Actividad "in vitro" de diferentes antibacterianos sobre bacilos gram-negativos no fermentadores, excluidos Pseudomonas aeruginosa y Acinetobacter spp ‘In vitro' activity of different antimicrobial agents on gram-negative nonfermentative bacilli, excluding Pseudomonas aeruginosa and Acinetobacter spp

    Directory of Open Access Journals (Sweden)

    C.A. Vay

    2005-03-01

    Full Text Available Los bacilos gram-negativos no fermentadores se encuentran ampliamente distribuidos en el medio ambiente. Además de causar dificultades en la identificación, a menudo presentan una marcada multirresistencia a los antimicrobianos incluyendo aquellos activos frente a Pseudomonas aeruginosa. El objetivo de este trabajo fue evaluar la actividad "in vitro" de diferentes antimicrobianos sobre 177 aislamientos de bacilos gram-negativos no fermentadores (excluidos Pseudomonas aeruginosa y Acinetobacter spp. provenientes de especimenes clínicos. Las concentraciones inhibitorias mínimas (CIM se determinaron por el método de dilución en agar Mueller Hinton frente a los siguientes antibacterianos: ampicilina, piperacilina, piperacilina-tazobactama, sulbactama, cefoperazona, cefoperazona-sulbactama, ceftazidima, cefepima, aztreonam, imipenem, meropenem, colistina, gentamicina, amicacina, trimetoprima-sulfametoxazol (TMS, cloranfenicol, eritromicina, rifampicina, norfloxacina, ciprofloxacina y minociclina. Sobre siete aislamientos: Sphingobacterium multivorum (2, Sphingobacterium spiritivorum (1, Empedobacter brevis (1, Weeksella virosa (1, Bergeyella zoohelcum (1 y Oligella urethralis (1 se ensayó la sensibilidad a amoxicilina-ácido clavulánico y ampicilina-sulbactama y no se determinó la actividad de cefoperazona ni de sulbactama. La multirresistencia fue comúnmente observada en los aislamientos de Stenotrophomonas maltophilia, Burkholderia cepacia, Chryseobacterium spp., Myroides spp., Achromobacter xylosoxidans y Ochrobactrum anthropi. En cambio, Pseudomonas stutzeri, Shewanella putrefaciens-algae, Sphingomonas paucimobilis, Pseudomonas oryzihabitans, Bergeyella zoohelcum, Weeksella virosa y Oligella urethralis, fueron ampliamente sensibles a los antibacterianos ensayados. Debido a la gran variabilidad observada en la sensibilidad a los antimicrobianos en las distintas especies, se hace imprescindible realizar la prueba de sensibilidad a los

  15. Effects of some organic pollutants on the exopolysaccharides (EPSs) produced by some Pseudomonas spp. strains

    International Nuclear Information System (INIS)

    Onbasli, Dilsad; Aslim, Belma

    2009-01-01

    In this study, isolation and characterization of exopolysaccharides produced by Pseudomonas aeruginosa B1, P. fluorescens B5, P. stutzeri B11 and P. putida B15 which had been seen to produce exopolymers of potential interest in biotechnological applications were examined. To initiate the observation of the organic pollutants-polymer interactions, the yield and properties of their extracellular polysaccharide were researched. The exopolysaccharide production by these strains during growth in nutrient broth medium (control) was 41-75 mg L -1 . Also, P. aeruginosa B1, P. fluorescens B5, P. stutzeri B11 and P. putida B15 had exhibited high production of EPSs in presence of various organic pollutants (2,4-D, benzene, BTX and gasoline, respectively) in mineral salt medium (MSM) as a sole carbon source. EPS production by the 4 strains ranged from 40 mg L -1 to 8 mg L -1 . Monosaccharide composition of EPS produced by these cultures were analyzed by HPLC. Results indicated that EPSs of strains contained neutral sugars and acetylated amino sugars. The neutral sugars in the EPS were mainly composed of glucose, arabinose, glycerol, ribose. The presence of galactronic acid, N-acetyl-D-galactosamin and N-acetyl-D-glucosamine indicated the acidic nature of the polysaccharide. Glycerol was the basic structural unit of EPS produced by the strains except P. stutzeri B11 (MSM with 1% BTX). Strain B1 (in NB medium) was found to be composed of neutral sugars (100%) while strain B1 [in MSM medium with 0.2% (v/v) 2.4-D] contained neutral sugars (70.0%), acetylated amino sugars (30.0%). Also, EPS content of strain B5 (in the NB medium) was neutral sugars (99.8%), acetylated amino sugars (0.2%) while the strain B5 [in MSM medium containing the 1% (v/v) benzene] was found to contain neutral sugars (99.9%), acetylated amino sugars (0.1%). However, EPS monomer composition by strain B11 was detected as neutral sugars (99.77%), acetylated amino sugars (0.23%) in NB medium while the strain B11

  16. Complete genome of Pseudomonas sp. strain L10.10, a psychrotolerant biofertilizer that could promote plant growth.

    Science.gov (United States)

    See-Too, Wah Seng; Lim, Yan-Lue; Ee, Robson; Convey, Peter; Pearce, David A; Yin, Wai-Fong; Chan, Kok Gan

    2016-03-20

    Pseudomonas sp. strain L10.10 (=DSM 101070) is a psychrotolerant bacterium which was isolated from Lagoon Island, Antarctica. Analysis of its complete genome sequence indicates its possible role as a plant-growth promoting bacterium, including nitrogen-fixing ability and indole acetic acid (IAA)-producing trait, with additional suggestion of plant disease prevention attributes via hydrogen cyanide production. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Aislamiento e identificaci?n de diez cepas bacterianas desnitrificantes a partir de un suelo agr?cola contaminado con abonos nitrogenados proveniente de una finca productora de cebolla en la Laguna de Tota, Boyac?, Colombia

    OpenAIRE

    Ostos Ortiz, Olga Lucia; Benavides L?pez de Mesa, Joaqu?n; Quintero, Gladys

    2006-01-01

    Este articulo presenta los resultados de la versatilidad adaptativa y tolerancia de una consorcio bacteriano constituido por 10 cepas bacterianas end?micas de un suelo agr?cola contaminado, proveniente de una finca productora de cebolla ubicada en la laguna de Tota en Aquitania, Boyac?, Colombia, expuesto al uso incontrolado de fertilizantes nitrogenados. La consorcio bacteriano aislado del suelo est? conformado por: Bacillus megaterium, Bacillus licheniformis, Pseudomonas stutzeri, Acinetoba...

  18. Exploration of indigenous bacteria in an intensive aquaculture system of African catfish (Clarias sp.) in Banyuwangi, Indonesia

    Science.gov (United States)

    Prayogo; Rahardja, B. S.; Asshanti, A. N.; Dewi, N. N.; Santanumurti, M. B.

    2018-04-01

    Intensive African catfish culture in tarpaulin pond was popular in Banyuwangi, Indonesia since the government supported the fisheries sector. Unfortunately, the failure of African catfish culture still occurred since the waste from fish metabolite process and feed residue decreased the water quality. Bacteria in the water could be the solution to increase the success rate of aquaculture by improving the water quality. This study purpose was to obtained indigenous bacteria in intensive aquaculture system of African catfish to improve water quality. This study successfully isolated bacteria contained with amylase, protease and lipase characteristic. Isolated bacteria in this study were identified as Pseudomonas pseudomallei (97.81%), Bacillus subtilis (95.81%) and Pseudomonas stutzeri (61.21%).

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

    Science.gov (United States)

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

    2010-03-01

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

  20. Occurrence of pseudomonas aeruginosa in post-operative wound infection

    International Nuclear Information System (INIS)

    Oguntibeju, O.O.; Nwobu, R.A.U.

    2004-01-01

    Objective: To determine the prevalence of Pseudomonas aeruginosa in post-operative wound infection. Results: Out of the 60 bacterial isolates found in post-operative wound infection, 20 (33.3%) were Pseudomonas aeruginosa, followed by Staphylococcus aureus 13(21.7%), Klebsiella species 10(16.7%), Escherichia coli 7(11.7%), Atypical coliform 4(6.7%), Proteus species 4(6.7%), Streptococcus pyogenes 1(1.7%) and Enterococcus faecalis 1(1.7%) in the order. Pseudomonas aeruginosa infections was higher in female than male, ratio 3:2 and was found more among young and elderly debilitated patients. The in vitro sensitivity pattern of 20 isolates of Pseudomonas aeruginosa showed colistin (100%), gentamicin (75%), streptomycin (30%), and tetracycline (10%). Conclusion: The role of Pseudomonas aeruginosa as an agent of nosocomial infection is re-emphasised. (author)

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

    African Journals Online (AJOL)

    ), P. fluorescens (13) and P. stutzeri (3) were isolated from Nigerian patients with burns, wound and skin infections, UTI, diarrhoea and eye infections. 81.5, 55.6, 76.9 and 33.3% of these species produced pyocins at a range of 410 – 670 g/ml.

  2. Denitrification of nitrate waste solutions

    International Nuclear Information System (INIS)

    Bertolami, R.J.; Chao, E.I.; Choi, W.M.; Johnson, B.R.; Varlet, J.L.P.

    1976-01-01

    Growth rates for the denitrifying bacteria Pseudomonas Stutzeri were studied to minimize the time necessary to start up a bacterial denitrification reactor. Batch experiments were performed in nine 250-ml Erlenmeyer flasks, a 7-liter fermentor, and a 67-liter fermentor. All reactors maintained an anaerobic environment. Initial microorganism inoculum concentration was varied over four orders of magnitude. Initial nitrate and substrate carbon concentrations were varied from 200 to 6000 ppm and from 56 to 1596 ppm, respectively, with a carbon-to-nitrogen weight ratio of 1.18. In all experiments, except those with the highest initial substrate-to-bacteria ratio, no growth was observed due to substrate depletion during the lag period. In those experiments which did exhibit an increase in bacterial population, growth also stopped due to substrate depletion. A model simulating microbe growth during the induction period was developed, but insufficient data were available to properly adjust the model constants. Because of this, the model does not accurately predict microbe growth. The metabolism of Pseudomonas Stutzeri was studied in detail. This resulted in a prediction of the denitrification stoichiometry during steady state reactor operation. Iron was found to be an important component for bacterial anabolism

  3. An altered Pseudomonas diversity is recovered from soil by using nutrient-poor Pseudomonas-selective soil extract media

    DEFF Research Database (Denmark)

    Aagot, N.; Nybroe, O.; Nielsen, P.

    2001-01-01

    We designed five Pseudomonas-selective soil extract NAA media containing the selective properties of trimethoprim and sodium lauroyl sarcosine and 0 to 100% of the amount of Casamino Acids used in the classical Pseudomonas-selective Gould's S1 medium. All of the isolates were confirmed to be Pseu......We designed five Pseudomonas-selective soil extract NAA media containing the selective properties of trimethoprim and sodium lauroyl sarcosine and 0 to 100% of the amount of Casamino Acids used in the classical Pseudomonas-selective Gould's S1 medium. All of the isolates were confirmed....... Several of these analyses showed that the amount of Casamino Acids significantly influenced the diversity of the recovered Pseudomonas isolates. Furthermore, the data suggested that specific Pseudomonas subpopulations were represented on the nutrient-poor media. The NAA 1:100 medium, containing ca. 15 mg...... of organic carbon per liter, consistently gave significantly higher Pseudomonas CFU counts than Gould's S1 when tested on four Danish soils. NAA 1:100 may, therefore, be a better medium than Gould's S1 for enumeration and isolation of Pseudomonas from the low-nutrient soil environment....

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

    African Journals Online (AJOL)

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

  5. Pseudomonas tarimensis sp. nov., an endophytic bacteria isolated from Populus euphratica.

    Science.gov (United States)

    Anwar, Nusratgul; Rozahon, Manziram; Zayadan, Bolatkhan; Mamtimin, Hormathan; Abdurahman, Mehfuzem; Kurban, Marygul; Abdurusul, Mihribangul; Mamtimin, Tursunay; Abdukerim, Muhtar; Rahman, Erkin

    2017-11-01

    An endophytic bacterium, MA-69 T , was isolated from the storage liquid in the stems of Populuseuphratica trees at the ancient Ugan River in Xinjiang, PR China. Strain MA-69 T was found to be short rod-shaped, Gram-stain-negative, non-spore-forming, aerobic and motile by means of a monopolar flagellum. According to phylogenetic analysis based on 16S rRNA gene sequences, strain MA-69 T was assigned to the genus Pseudomonas with highest 16S rRNA gene sequence similarity of 97.5 % to Pseudomonas azotifigens JCM 12708 T , followed by Pseudomonas matsuisoli JCM 30078 T (97.5 %), Pseudomonas balearica DSM 6083 T (97.1 %), Azotobacter salinestris ATCC 49674 T (96.1 %) and Pseudomonas indica DSM 14015 T (95.9 %). Analysis of strain MA-69 T based on the three housekeeping genes, rpoB, rpoD and gyrB, further confirmed the isolate to be distinctly delineated from species of the genus Pseudomonas. The DNA G+C content of strain MA-69 T was 64.1 mol%. DNA-DNA hybridization with Pseudomonas azotifigens JCM 12708 T , Pseudomonas matsuisoli JCM 30078 T and Pseudomonas balearica DSM 6083 T revealed 62.9, 60.1 and 49.0 % relatedness, respectively. The major fatty acids in strain MA-69 T were summed feature 3 (25.7 %), summed feature 8 (24.0 %), C19 : 0cyclo ω8c (19.9 %), C16 : 0 (14.6 %) and C12 : 0 (6.3 %). The major polar lipids were phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol. Q-9 was the major quinone in strain MA-69 T . Based on phenotypic, chemotaxonomic and phylogenetic properties, strain MA-69 T represents a novel species of the genus Pseudomonas, for which the name Pseudomonas tarimensis sp. nov. is proposed. The type strain is MA-69 T (=CCTCC AB 2013065 T =KCTC 42447 T ).

  6. Aislamiento de microorganismos productores de biosurfactantes y lipasas a partir de efluentes residuales de camales y suelos contaminados con hidrocarburos

    Directory of Open Access Journals (Sweden)

    Lizzie Karen Becerra Gutiérrez

    2016-01-01

    Full Text Available Los biosurfactantes son moléculas anfipáticas que reducen la tensión en la interfase, incrementando así la solubilidad en agua y disponibilidad de compuestos orgánicos, son producidos por bacterias, hongos, y levaduras. Para el aislamiento de bacterias productoras de biosurfactante y lipasas, se sembró en medios inductores 10% de efluentes residuales procedentes de camales y suelos de grifos contaminados con hidrocarburos de la Provincia de Trujillo - Perú. Los cultivos aislados se sembraron en agar lecitina y agar rodamina para la determinación de productores de lipasas. Los microorganismos seleccionados se sembraron en agar sangre y agar Siegmund y Wagner (SW para la selección preliminar de bacterias biosurfactantes. Posteriormente se determinó a aquellos microorganismos productores de surfactantes mediante Índice de Emulsificación (IE y Medición de la Tensión superficial. Los cultivos positivos a estas pruebas fueron seleccionados e identificados mediante galerías API e identificación molecular por secuenciamiento de ADN. Los cultivos que redujeron en mayor medida la tensión superficial fueron P. aeruginosa y B. amyloliquefaciens, llegando a reducir la tensión superficial a 27,2 ± 0,4 y 31,03 ± 0,4 mN/m respectivamente, mientras que P. stutzeri y Pseudomonas sp. redujeron la tensión superficial a 48,3 y 52,6 ± 0,4 mN/m respectivamente. Se concluye, por tanto, que se obtuvo 49 cultivos productores de lipasas de la provincia de Trujillo, de los cuales se determinó que Pseudomonas stutzeri, Pseudomonas sp, Pseudomonas aeruginosa y Bacillus amyloliquefaciens son productores de biosurfactantes y pueden aplicarse en el área de la biotecnología ambiental para la remoción y biodegradación de contaminantes.

  7. 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 syringae...

  8. 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?

  9. Isolation, identification, and pathological effects of beach sand bacterial extract on human skin keratinocytes in vitro

    Directory of Open Access Journals (Sweden)

    Fazli Subhan

    2018-01-01

    Full Text Available Background Beaches are recreational spots for people. However, beach sand contains harmful microbes that affect human health, and there are no established methods for either sampling and identifying beach-borne pathogens or managing the quality of beach sand. Method This study was conducted with the aim of improving human safety at beaches and augmenting the quality of the beach experience. Beach sand was used as a resource to isolate bacteria due to its distinctive features and the biodiversity of the beach sand biota. A selected bacterial isolate termed FSRS was identified as Pseudomonas stutzeri using 16S rRNA sequencing and phylogenetic analysis, and the sequence was deposited in the NCBI GenBank database under the accession number MF599548. The isolated P. stutzeri bacterium was cultured in Luria–Bertani growth medium, and a crude extract was prepared using ethyl acetate to examine the potential pathogenic effect of P. stutzeri on human skin. A human skin keratinocyte cell line (HaCaT was used to assess cell adhesion, cell viability, and cell proliferation using a morphological analysis and a WST-1 assay. Result The crude P. stutzeri extract inhibited cell adhesion and decreased cell viability in HaCaT cells. We concluded that the crude extract of P. stutzeri FSRS had a strong pathological effect on human skin cells. Discussion Beach visitors frequently get skin infections, but the exact cause of the infections is yet to be determined. The beach sand bacterium P. stutzeri may, therefore, be responsible for some of the dermatological problems experienced by people visiting the beach.

  10. Identification, recombinant production and partial biochemical characterization of an extracellular cold-active serine-metalloprotease from an Antarctic Pseudomonas isolate

    Directory of Open Access Journals (Sweden)

    Natalia Fullana

    2017-08-01

    Full Text Available Cold-adapted enzymes are generally derived from psychrophilic microorganisms and have features that make them very attractive for industrial and biotechnological purposes. In this work, we identified a 50 kDa extracellular protease (MP10 from the Antarctic isolate Pseudomonas sp. AU10. The enzyme was produced by recombinant DNA technology, purified using immobilized metal affinity chromatography and partially characterized. MP10 is an alkaline thermosensitive serine-metallo protease with optimal activity at pH 8.0 and 40 ℃, in the presence of 1.5 mM Ca2+. MP10 showed 100% residual activity and stability (up to 60 min when incubated with 7% of non-ionic surfactants (Triton X-100, Tween-80 and Tween-20 and 1.5% of the oxidizing agent hydrogen peroxide. The 3D MP10 structure was predicted and compared with the crystal structure of mesophilic homologous protease produced by Pseudomonas aeruginosa PA01 (reference strain and other proteases, showing similarity in surface area and volume of proteins, but a significantly higher surface pocket area and volume of MP10. The observed differences presumably may explain the enhanced activity of MP10 for substrate binding at low temperatures. These results give insight to the potential use of MP10 in developing new biotechnologically processes active at low to moderate temperatures, probably with focus in the detergent industry.

  11. ANTIMICROBIAL ACTIVITY OF PINEAPPLE (ANANAS COMOSUS L. MERR EXTRACT AGAINST MULTIDRUG-RESISTANT OF PSEUDOMONAS AERUGINOSA: AN IN VITRO STUDY

    Directory of Open Access Journals (Sweden)

    Rahmat Sayyid Zharfan

    2017-08-01

    Full Text Available Pseudomonas aeruginosa is the main cause of nosocomial infection which is responsible for 10% of hospital-acquired infection. Pseudomonas aeruginosa tends to mutate and displays potential for development of antibiotic resistance. Approximately, 10% of global bacterial isolates are found as Multidrug-resistant Pseudomonas aeruginosa. Pseudomonas aeruginosa have a quite tremendous severity index, especially on pneumonia and urinary tract infections, even sepsis, which 50% mortality rate. Pineapple (Ananas comosus L. Merr has antimicrobial properties. The active antimicrobial compounds in Ananas comosus L. Merr include saponin and bromelain. This research aims to find the potency of antimicrobial effect of pineapple (Ananas comosus L. Merr extract towards Multidrug-resistant Pseudomonas aeruginosa. Multidrug-resistant Pseudomonas aeruginosa specimen is obtained from patient’s pus in orthopaedic department, Dr Soetomo Public Hospital, Surabaya. Multidrug-resistant Pseudomonas aeruginosa specimen is resistant to all antibiotic agents except cefoperazone-sulbactam. This research is conducted by measuring the Minimum Inhibitory Concentration (MIC through dilution test with Mueller-Hinton broth medium. Pineapple extract (Ananas comosus L. Merr. is dissolved in aquadest, then poured into test tube at varying concentrations (6 g/ml; 3 g/ml; 1.5 g/ml; 0.75 g/ml, 0.375 g/ml; and 0.1875 g/ml. After 24 hours’ incubation, samples are plated onto nutrient agar plate, to determine the Minimum Bactericidal Concentration (MBC. The extract of pineapple (Ananas comosus L. Merr has antimicrobial activities against Multidrug-resistant Pseudomonas aeruginosa. Minimum Inhibitory Concentration (MIC could not be determined, because turbidity changes were not seen. The Minimum Bactericidal Concentration (MBC of pineapple extract (Ananas comosus L. Merr to Multidrug-resistant Pseudomonas aeruginosa is 0.75 g/ml. Further study of in vivo is needed.

  12. Radionuclides can be mobilized by bacteria from the subsurface grown under aerobic as well as anaerobic conditions

    International Nuclear Information System (INIS)

    Johnsson, A.; Arlinger, J.; Pedersen, K.; Albinsson, Y.; Andlid, T.

    2005-01-01

    Full text of publication follows: Microbes can influence radionuclide mobility in many ways. They can change the pH or redox of their surroundings, act as nucleation sites for precipitation, transport metals sorbed to the cell surface and excrete organic compounds that form mobile radionuclide complexes. The processes behind bio-mobilization of radionuclides are important to study as they may have implications on e g radioactive waste disposal. Three bacterial species; Pseudomonas fluorescens, Pseudomonas stutzeri and Shewanella putrefaciens were selected for this study. All bacteria were grown under aerobic conditions and P. stutzeri and S. putrefaciens were also grown under anaerobic conditions. Aerobic and anaerobic cultures were centrifuged after having reached stationary phase. The supernatants, containing the exudates of the bacteria, were collected. 59 Fe(III), 147 Pm(III), 234 Th(IV) and 241 Am(III) were added to the supernatants and SiO 2 was added to the supernatant radionuclide mix. The amount of radionuclide in the liquid phase was analyzed using liquid scintillation counting and Na-I gamma spectrometry. Supernatants of all three species of aerobically grown bacteria mobilize more than 60% of all four radionuclides. High performance liquid chromatography (HPLC) analysis detected four Fe-complexing substances in the supernatant of P. fluorescens and two peaks and one peak, respectively, in the supernatants of P. stutzeri and S. putrefaciens. All substances eluted from the column varied in retention times, indicating that the microbes produced several metabolites that have different complexing abilities. Comparing HPLC data with mobilization data show that P. fluorescens mobilizes the largest percentage of radionuclide and S. putrefaciens mobilizes the least amount of radionuclides in all cases. Like aerobic supernatants the supernatants of anaerobically grown bacteria test positive for siderophores. Despite this 59 Fe(III) shows no net mobilization

  13. Insertion sequence ISRP10 inactivation of the oprD gene in imipenem-resistant Pseudomonas aeruginosa clinical isolates.

    Science.gov (United States)

    Sun, Qinghui; Ba, Zhaofen; Wu, Guoying; Wang, Wei; Lin, Shuxiang; Yang, Hongjiang

    2016-05-01

    Carbapenem resistance mechanisms were investigated in 32 imipenem-resistant Pseudomonas aeruginosa clinical isolates recovered from hospitalised children. Sequence analysis revealed that 31 of the isolates had an insertion sequence element ISRP10 disrupting the porin gene oprD, demonstrating that ISRP10 inactivation of oprD conferred imipenem resistance in the majority of the isolates. Multilocus sequence typing (MLST) was used to discriminate the isolates. In total, 11 sequence types (STs) were identified including 3 novel STs, and 68.3% (28/41) of the tested strains were characterised as clone ST253. In combination with random amplified polymorphic DNA (RAPD) analysis, the imipenem-resistant isolates displayed a relatively high degree of genetic variability and were unlikely associated with nosocomial infections. Copyright © 2016 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved.

  14. Pseudomonas aeruginosa multiresistente em unidade de cuidados intensivos: desafios que procedem? Pseudomonas aeruginosa multiresistente en una unidad de cuidados intensivos: desafíos que proceden? Multi-resistant pseudomonas aeruginosa among patients from an intensive care unit: persistent challenge?

    Directory of Open Access Journals (Sweden)

    Maria Verônica Guilherme Ferrareze

    2007-03-01

    Full Text Available OBJETIVOS: Avaliar a ocorrência de infecção hospitalar por Pseudomonas aeruginosa multiresistente em pacientes hospitalizados em uma unidade de cuidados intensivos. MÉTODO: estudo retrospectivo realizado de outubro de 2003 a setembro de 2004 em um hospital de emergências. RESULTADOS: Totalizou-se 68 portadores de bactérias multiresistentes sendo 10 (14,7% de P. aeruginosa. Destes, 8 pacientes eram do sexo masculino, as médias de idade e de internação foram respectivamente de 57 anos a média de idade, 43,7 a média de dias de internação e 7 pacientes morreram. Isolaram-se 8 cepas no sangue, cinco na urina, duas em cateteres venosos e uma no líquor, das quais sete sensíveis somente a polimixina e três ao imipenem. CONCLUSÃO: O perfil microbiológico deve ser avaliado periodicamente visto que é específico de uma unidade ou instituição, e demanda ações correlatas.OBJETIVOS: Evaluar la ocurrencia de infección hospitalaria por Pseudomonas aeruginosa multiresistente en pacientes hospitalizados en una unidad de cuidados intensivos. MÉTODO: estudio retrospectivo realizado de octubre del 2003 a setiembre del 2004 en un hospital de emergencias. RESULTADOS: Se tuvo un total de 68 portadores de bacterias multiresistentes de las cuales 10 (14,7% de P. aeruginosa. De éstos, 8 pacientes eran del sexo masculino, los promedios de edad y de internamiento fueron respectivamente de 57 años y 43,7 de días de internamiento y 7 pacientes murieron. Se aislaron 8 cepas en la sangre, cinco en la orina, dos en catéteres venosos y una en el licor, de ellas siete eran sensibles sólo a la polimixina y tres al imipenem. CONCLUSIÓN: El perfil microbiológico debe ser evaluado periódicamente dado que es específico de una unidad o institución, y demanda acciones correlatas.OBJECTIVES: To evaluate the occurrence of multi-resistant Pseudomonas Aeruginosa infection among patients from an Intensive Care Unit. METHODS: This retrospective study was

  15. AcEST: DK946915 [AcEST

    Lifescience Database Archive (English)

    Full Text Available Meth... 31 3.7 sp|A4VKN0|DNLJ_PSEU5 DNA ligase OS=Pseudomonas stutzeri (strain ... 31 3.7 sp|Q9P287|BCCI...VHVPEQCPVCGSAVERTQLIKRSKGRESVSEGSIYR 447 >sp|Q9P287|BCCIP_HUMAN BRCA2 and CDKN1A-...interacting protein OS=Homo sapiens GN=BCCIP PE=1 SV=1 Length = 314 Score = 31.2 bits (69), Expect = 3.7 Ide

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

    African Journals Online (AJOL)

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

  17. Pseudomonas versuta sp. nov., isolated from Antarctic soil.

    Science.gov (United States)

    See-Too, Wah Seng; Salazar, Sergio; Ee, Robson; Convey, Peter; Chan, Kok-Gan; Peix, Álvaro

    2017-06-01

    In this study we analysed three bacterial strains coded L10.10 T , A4R1.5 and A4R1.12, isolated in the course of a study of quorum-quenching bacteria occurring in Antarctic soil. The 16S rRNA gene sequence was identical in the three strains and showed 99.7% pairwise similarity with respect to the closest related species Pseudomonas weihenstephanensis WS4993 T . Therefore, the three strains were classified within the genus Pseudomonas. Analysis of housekeeping genes (rpoB, rpoD and gyrB) sequences showed similarities of 84-95% with respect to the closest related species of Pseudomonas, confirming its phylogenetic affiliation. The ANI values were less than 86% to the closest related species type strains. The respiratory quinone is Q9. The major fatty acids are C16:0, C16:1 ω7c/ C16:1 ω6c in summed feature 3 and C18:1 ω7c / C18:1 ω6c in summed feature 8. The strains are oxidase- and catalase-positive. Growth occurs at 4-30°C, and at pH 4.0-10. The DNA G+C content is 58.2-58.3mol %. The combined genotypic, phenotypic and chemotaxonomic data support the classification of strains L10.10 T , A4R1.5 and A4R1.12 into a novel species of Pseudomonas, for which the name P. versuta sp. nov. is proposed. The type strain is L10.10 T (LMG 29628 T , DSM 101070 T ). Copyright © 2017 Elsevier GmbH. All rights reserved.

  18. [Pseudomonas infection: biological risk by occupational exposure and results of an environmental monitoring].

    Science.gov (United States)

    Massoni, Francesco; Giorgi, Doriana Antonella; Palmieri, Sabina; Arcangeli, Luca; Ricci, Serafino

    2014-01-01

    The biological risk of Pseudomonas aeruginosa for activities involving exposure to contaminated water, such as, for example, routine maintenance of swimming pools, is related to the availability of effective prophylactic and therapeutic measures. The authors present the data of the microbiological analyzes made on 2349 samples taken from pools in Rome and province. The contamination by Pseudomonas was found in 191 samples with 13 samples that had a level > 100 cfu/100 ml and 5 samples with level > 200 cfu/100 ml. Useful considerations derived from the analysis of the literature about the profile and prophylactic treatment of infection by Pseudomonas, necessarily to be taken into consideration for an adequate risk assessment.

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

    African Journals Online (AJOL)

    USER

    2010-02-08

    Feb 8, 2010 ... ambient temperature in the reaction system, the efficiency of nitrogen removal was studied. The results ... no reported experiment which has been conducted to ... controlled shaker at 32°C with a 150 r/min rotating speed (Ahn,.

  20. Pseudomonas aeruginosa outbreak in a pediatric oncology care unit caused by an errant water jet into contaminated siphons.

    Science.gov (United States)

    Schneider, Henriette; Geginat, Gernot; Hogardt, Michael; Kramer, Alexandra; Dürken, Matthias; Schroten, Horst; Tenenbaum, Tobias

    2012-06-01

    We analyzed an outbreak of invasive infections with an exotoxin U positive Pseudomonas aeruginosa strain within a pediatric oncology care unit. Environmental sampling and molecular characterization of the Pseudomonas aeruginosa strains led to identification of the outbreak source. An errant water jet into the sink within patient rooms was observed. Optimized outbreak management resulted in an abundance of further Pseudomonas aeruginosa infections within the pediatric oncology care unit.

  1. Pseudomonas mesophilica and an unnamed taxon, clinical isolates of pink-pigmented oxidative bacteria.

    OpenAIRE

    Gilardi, G L; Faur, Y C

    1984-01-01

    Twenty-one strains of pink-pigmented bacteria, isolated from human clinical specimens and an environmental source, were compared with Pseudomonas mesophilica ATCC 29983 and Protaminobacter ruber ATCC 8457. These isolates were gram-negative, oxidative rods which were motile by means of a single polar flagellum; gave positive catalase, indophenol oxidase, urease, and amylase reactions; and grew slowly at 30 degrees C. Fourteen isolates conformed to the designated type strains Pseudomonas mesoph...

  2. Lipase From Thermoalkalophilic Pseudomonas species as an Additive in Potential Laundry Detergent Formulations

    Directory of Open Access Journals (Sweden)

    Ibrahim, C. O.

    2009-01-01

    Full Text Available Lipase isolated from a thermoalkalophilic Pseudomonas species was used as additive to improve the degree of olive oil removal from cotton fabric in the presence of surfactants. The lipase used in this study was found to be more effective with non ionic surfactants as compared to ionic surfactants. In terms of stability, there was no decrease in activity found in the presence of Tween 85, Span 80 and Span 20. Lipase from Pseudomonas species was most active in the presence of Tween 85, Span 80 and Span 20. The application of lipase from Pseudomonas species as an additive in the formulation containing Span 80 has improved oil removal by 36% using the washing system consisting 5 U/mL lipase, at 70 °C for 20 min and 0.8% of Span 80 as surfactant. Considering that lipase from Pseudomonas species is stable in high pH and temperatures in the presence of various surfactants, therefore it is suitable to be incorporated as additives in potential detergent formulations.

  3. Microbial pathways for the mobilization of mercury as Hg(O) in anoxic subsurface environments

    Energy Technology Data Exchange (ETDEWEB)

    Barkay, Tamar

    2005-06-01

    The goal of our project which was initiated in June 2005 is focused on the presence of merA in microbial communities of anoxic environments and the effect of anaerobic respiratory pathways on MR expression and activities. The following progress has been made to date: PCR primers were designed to span the known phylogenetic range of merA genes of Gram-negative bacteria. In control experiments, these primers successfully amplified a 288 bp region at the 3? end of previously characterized merA genes from Shewanella putrefaciens pMERPH, Acidithiobacillus ferrooxidans, Pseudomonas stutzeri pPB, Tn5041, Pseudomonas sp. K-62, and Serratia marcescens pDU1358.

  4. Impact of Ag and Al2O3 nanoparticles on soil organisms: In vitro and soil experiments

    International Nuclear Information System (INIS)

    Fajardo, C.; Saccà, M.L.; Costa, G.; Nande, M.; Martin, M.

    2014-01-01

    In vitro analyses were conducted to assess the impact of Al 2 O 3 and Ag nanoparticles on two common soil bacteria, Bacillus cereus and Pseudomonas stutzeri. Al 2 O 3 nanoparticles did not show significant toxicity at any dose or time assayed, whereas exposure to 5 mg L −1 Ag nanoparticles for 48 h caused bactericidal effects. Moreover, alterations at the morphological level were observed by transmission electron microscopy (TEM); Ag but not Al 2 O 3 nanoparticles evoked the entrance of B. cereus cells in an early sporulation stage and both nanoparticles penetrated P. stutzeri cells. At the molecular level, a dramatic increase (8.2-fold) in katB gene expression was found in P. stutzeri following Al 2 O 3 nanoparticles exposure, indicative of an oxidative stress-defence system enhancement in this bacterium. In the microcosm experiment, using two different natural soils, Al 2 O 3 or Ag nanoparticles did not affect the Caenorhabditis elegans toxicity endpoints growth, survival, or reproduction. However, differences in microbial phylogenetic compositions were detected by fluorescence in situ hybridization (FISH). The use of katB- and pykA-based sequences showed that the microbial transcriptional response to nanoparticle exposure decreased, suggesting a decrease in cellular activity. These changes were attributable to both the nanoparticles treatment and soil characteristics, highlighting the importance of considering the soil matrix on a case by case basis. - Highlights: • Al 2 O 3 or Ag NPs impact on bacteria was assessed at phenotypic and molecular level. • katB gene involved in oxidative-stress response was overexpressed in P. stutzeri following Al 2 O 3 NPs exposure. • A decrease in bacterial transcriptional response was detected in NPs-treated soils. • A soil-dependent response to specific NP treatment was observed. • In NPs-treated soils no acute toxic effects on C. elegans were found

  5. Pseudomonas mesophilica and an unnamed taxon, clinical isolates of pink-pigmented oxidative bacteria.

    Science.gov (United States)

    Gilardi, G L; Faur, Y C

    1984-10-01

    Twenty-one strains of pink-pigmented bacteria, isolated from human clinical specimens and an environmental source, were compared with Pseudomonas mesophilica ATCC 29983 and Protaminobacter ruber ATCC 8457. These isolates were gram-negative, oxidative rods which were motile by means of a single polar flagellum; gave positive catalase, indophenol oxidase, urease, and amylase reactions; and grew slowly at 30 degrees C. Fourteen isolates conformed to the designated type strains Pseudomonas mesophilica ATCC 29983 and Protaminobacter ruber ATCC 8457. The remaining seven strains represented an undescribed taxon. These pink bacteria appear to be invaders of debilitated patients with an underlying chronic disease.

  6. Nitrate reduction by fungi in marine oxygen-depleted laboratory microcosms

    Digital Repository Service at National Institute of Oceanography (India)

    Manohar, C.S.; Raghukumar, C.

    in terrestrial soils (Laughlin et al. 2009). Studies on denitrification in wetlands indicate that both bacteria and fungi contribute significantly to denitrification under reducing conditions. However, fungal denitrification might well be of greater ecological... such as grassland soil (Laughlin and Stevens 2002), fumigated soil (Spokas et al. 2006) and woodland (Castaldi and Smith 1998). Mixed cultures of the fungus Fusarium oxysporum and the bacterium Pseudomonas stutzeri (Lehmann and Neumann) Sijderius under anaerobic...

  7. CXCR1 regulates pulmonary anti-Pseudomonas host defense

    Science.gov (United States)

    Carevic, M.; Öz, H.; Fuchs, K.; Laval, J.; Schroth, C.; Frey, N.; Hector, A.; Bilich, T.; Haug, M.; Schmidt, A.; Autenrieth, S. E.; Bucher, K.; Beer-Hammer, S.; Gaggar, A.; Kneilling, M.; Benarafa, C.; Gao, J.; Murphy, P.; Schwarz, S.; Moepps, B.; Hartl, D.

    2016-01-01

    Pseudomonas aeruginosa is a key opportunistic pathogen causing disease in cystic fibrosis (CF) and other lung diseases such as chronic obstructive pulmonary disease (COPD). However, the pulmonary host defense mechanisms regulating anti-Pseudomonas aeruginosa immunity remain incompletely understood. Here we demonstrate, by studying an airway Pseudomonas aeruginosa infection model, in vivo bioluminescence imaging, neutrophil effector responses and human airway samples, that the chemokine receptor CXCR1 regulates pulmonary host defense against Pseudomonas aeruginosa. Mechanistically, CXCR1 regulated anti-Pseudomonas neutrophil responses through modulation of reactive oxygen species and interference with toll-like receptor 5 expression. These studies define CXCR1 as a novel non-canonical chemokine receptor that regulates pulmonary anti-Pseudomonas host defense with broad implications for CF, COPD and other infectious lung diseases. PMID:26950764

  8. Pseudomonas predators: understanding and exploiting phage-host interactions.

    Science.gov (United States)

    De Smet, Jeroen; Hendrix, Hanne; Blasdel, Bob G; Danis-Wlodarczyk, Katarzyna; Lavigne, Rob

    2017-09-01

    Species in the genus Pseudomonas thrive in a diverse set of ecological niches and include crucial pathogens, such as the human pathogen Pseudomonas aeruginosa and the plant pathogen Pseudomonas syringae. The bacteriophages that infect Pseudomonas spp. mirror the widespread and diverse nature of their hosts. Therefore, Pseudomonas spp. and their phages are an ideal system to study the molecular mechanisms that govern virus-host interactions. Furthermore, phages are principal catalysts of host evolution and diversity, which directly affects the ecological roles of environmental and pathogenic Pseudomonas spp. Understanding these interactions not only provides novel insights into phage biology but also advances the development of phage therapy, phage-derived antimicrobial strategies and innovative biotechnological tools that may be derived from phage-bacteria interactions.

  9. Quick change: post-transcriptional regulation in Pseudomonas.

    Science.gov (United States)

    Grenga, Lucia; Little, Richard H; Malone, Jacob G

    2017-08-01

    Pseudomonas species have evolved dynamic and intricate regulatory networks to fine-tune gene expression, with complex regulation occurring at every stage in the processing of genetic information. This approach enables Pseudomonas to generate precise individual responses to the environment in order to improve their fitness and resource economy. The weak correlations we observe between RNA and protein abundance highlight the significant regulatory contribution of a series of intersecting post-transcriptional pathways, influencing mRNA stability, translational activity and ribosome function, to Pseudomonas environmental responses. This review examines our current understanding of three major post-transcriptional regulatory systems in Pseudomonas spp.; Gac/Rsm, Hfq and RimK, and presents an overview of new research frontiers, emerging genome-wide methodologies, and their potential for the study of global regulatory responses in Pseudomonas. © FEMS 2017.

  10. Rapid monitoring of intermediate states and mass balance of nitrogen during denitrification by means of cavity enhanced Raman multi-gas sensing

    Energy Technology Data Exchange (ETDEWEB)

    Keiner, Robert [Institute of Physical Chemistry, Friedrich Schiller University Jena, Jena 07743 (Germany); Leibniz Institute of Photonic Technology, Jena 07745 (Germany); Herrmann, Martina; Küsel, Kirsten [Institute of Ecology, Friedrich Schiller University Jena, Jena 07743 (Germany); German Centre for Integrative Biodiversity Research (iDiv) Halle–Jena–Leipzig, Leipzig 04103 (Germany); Popp, Jürgen [Institute of Physical Chemistry, Friedrich Schiller University Jena, Jena 07743 (Germany); Leibniz Institute of Photonic Technology, Jena 07745 (Germany); InfectoGnostics Forschungscampus, Zentrum für Angewandte Forschung, Jena 07743 (Germany); Abbe School of Photonics, Friedrich Schiller University, Jena (Germany); Frosch, Torsten, E-mail: torsten.frosch@uni-jena.de [Institute of Physical Chemistry, Friedrich Schiller University Jena, Jena 07743 (Germany); Leibniz Institute of Photonic Technology, Jena 07745 (Germany); InfectoGnostics Forschungscampus, Zentrum für Angewandte Forschung, Jena 07743 (Germany)

    2015-03-15

    Highlights: • CERS is a versatile new analytical methodology. • Continuous online quantification of reduction of {sup 15}N-labelled nitrate by P. stutzeri was demonstrated. • The total nitrogen element budget was monitored online for the first time. • Sterile online acquisition of the pH changes in the P. stutzeri culture was demonstrated. • An increased slope of the pH value coincided with a temporary accumulation of N{sub 2}O. - Abstract: The comprehensive investigation of changes in N cycling has been challenging so far due to difficulties with measuring gases such as N{sub 2} and N{sub 2}O simultaneously. In this study we introduce cavity enhanced Raman gas spectroscopy as a new analytical methodology for tracing the stepwise reduction of {sup 15}N-labelled nitrate by the denitrifying bacteria Pseudomonas stutzeri. The unique capabilities of Raman multi-gas analysis enabled real-time, continuous, and non-consumptive quantification of the relevant gases ({sup 14}N{sub 2}, {sup 14}N{sub 2}O, O{sub 2}, and CO{sub 2}) and to trace the fate of {sup 15}N-labeled nitrate substrate ({sup 15}N{sub 2}, {sup 15}N{sub 2}O) added to a P. stutzeri culture with one single measurement. Using this new methodology, we could quantify the kinetics of the formation and degradation for all gaseous compounds (educts and products) and thus study the reaction orders. The gas quantification was complemented with the analysis of nitrate and nitrite concentrations for the online monitoring of the total nitrogen element budget. The simultaneous quantification of all gases also enabled the contactless and sterile online acquisition of the pH changes in the P. stutzeri culture by the stoichiometry of the redox reactions during denitrification and the CO{sub 2}-bicarbonate equilibrium. Continuous pH monitoring – without the need to insert an electrode into solution – elucidated e.g. an increase in the slope of the pH value coinciding with an accumulation of nitrite, which in

  11. Reduction in Fluoroquinolone Use following Introduction of Ertapenem into a Hospital Formulary Is Associated with Improvement in Susceptibility of Pseudomonas aeruginosa to Group 2 Carbapenems: a 10-Year Study▿

    Science.gov (United States)

    Cook, Paul P.; Gooch, Michael; Rizzo, Shemra

    2011-01-01

    We examined the effect of the addition of ertapenem to our hospital formulary on the resistance of nosocomial Pseudomonas aeruginosa to group 2 carbapenems (imipenem, meropenem, and doripenem). This was a retrospective, observational study conducted between 1 January 2000 and 31 January 2009 at a large, tertiary-care hospital. Autoregressive integrated moving average (ARIMA) regression models were used to evaluate the effect of ertapenem use on the susceptibility of Pseudomonas aeruginosa to group 2 carbapenems as well as on the use of the group 2 carbapenems, ciprofloxacin, and other antipseudomonal drugs (i.e., tobramycin, cefepime, and piperacillin-tazobactam). Resistance was expressed as a percentage of total isolates as well as the number of carbapenem-resistant bacterial isolates per 10,000 patient days. Pearson correlation was used to assess the relationship between antibiotic use and carbapenem resistance. Following the addition of ertapenem to the formulary, there was a statistically significant decrease in the percentage of Pseudomonas aeruginosa isolates resistant to the group 2 carbapenems (P = 0.003). Group 2 carbapenem use and the number of carbapenem-resistant Pseudomonas aeruginosa isolates per 10,000 patient days did not change significantly over the time period. There was a large decrease in the use of ciprofloxacin (P = 0.0033), and there was a correlation of ciprofloxacin use with the percentage of isolates resistant to the group 2 carbapenems (ρ = 0.47, P = 0.002). We suspect that the improvement in susceptibility of Pseudomonas aeruginosa to group 2 carbapenems was related to a decrease in ciprofloxacin use. PMID:21968357

  12. Reduction in fluoroquinolone use following introduction of ertapenem into a hospital formulary is associated with improvement in susceptibility of Pseudomonas aeruginosa to group 2 carbapenems: a 10-year study.

    Science.gov (United States)

    Cook, Paul P; Gooch, Michael; Rizzo, Shemra

    2011-12-01

    We examined the effect of the addition of ertapenem to our hospital formulary on the resistance of nosocomial Pseudomonas aeruginosa to group 2 carbapenems (imipenem, meropenem, and doripenem). This was a retrospective, observational study conducted between 1 January 2000 and 31 January 2009 at a large, tertiary-care hospital. Autoregressive integrated moving average (ARIMA) regression models were used to evaluate the effect of ertapenem use on the susceptibility of Pseudomonas aeruginosa to group 2 carbapenems as well as on the use of the group 2 carbapenems, ciprofloxacin, and other antipseudomonal drugs (i.e., tobramycin, cefepime, and piperacillin-tazobactam). Resistance was expressed as a percentage of total isolates as well as the number of carbapenem-resistant bacterial isolates per 10,000 patient days. Pearson correlation was used to assess the relationship between antibiotic use and carbapenem resistance. Following the addition of ertapenem to the formulary, there was a statistically significant decrease in the percentage of Pseudomonas aeruginosa isolates resistant to the group 2 carbapenems (P = 0.003). Group 2 carbapenem use and the number of carbapenem-resistant Pseudomonas aeruginosa isolates per 10,000 patient days did not change significantly over the time period. There was a large decrease in the use of ciprofloxacin (P = 0.0033), and there was a correlation of ciprofloxacin use with the percentage of isolates resistant to the group 2 carbapenems (ρ = 0.47, P = 0.002). We suspect that the improvement in susceptibility of Pseudomonas aeruginosa to group 2 carbapenems was related to a decrease in ciprofloxacin use.

  13. Prevalence of antibacterial resistant bacterial contaminants from mobile phones of hospital inpatients.

    Science.gov (United States)

    Vinod Kumar, B; Hobani, Yahya Hasan; Abdulhaq, Ahmed; Jerah, Ahmed Ali; Hakami, Othman M; Eltigani, Magdeldin; Bidwai, Anil K

    2014-01-01

    Mobile phones contaminated with bacteria may act as fomites. Antibiotic resistant bacterial contamination of mobile phones of inpatients was studied. One hundred and six samples were collected from mobile phones of patients admitted in various hospitals in Jazan province of Saudi Arabia. Eighty-nine (83.9%) out of 106 mobile phones were found to be contaminated with bacteria. Fifty-two (49.0%) coagulase-negative Staphylococcus, 12 (11.3%) Staphylococcus aureus, 7 (6.6%) Enterobacter cloacae, 3 (2.83%) Pseudomonas stutzeri, 3 (2.83%) Sphingomonas paucimobilis, 2 (1.8%) Enterococcus faecalis and 10 (9.4%) aerobic spore bearers were isolated. All the isolated bacteria were found to be resistant to various antibiotics. Hence, regular disinfection of mobile phones of hospital inpatients is advised.

  14. Quantitative approach to track lipase producing Pseudomonas sp. S1 in nonsterilized solid state fermentation.

    Science.gov (United States)

    Sahoo, R K; Subudhi, E; Kumar, M

    2014-06-01

    Proliferation of the inoculated Pseudomonas sp. S1 is quantitatively evaluated using ERIC-PCR during the production of lipase in nonsterile solid state fermentation an approach to reduce the cost of enzyme production. Under nonsterile solid state fermentation with olive oil cake, Pseudomonas sp. S1 produced 57·9 IU g(-1) of lipase. DNA fingerprints of unknown bacterial isolates obtained on Bushnell Haas agar (BHA) + tributyrin exactly matched with that of Pseudomonas sp. S1. Using PCR-based enumeration, population of Pseudomonas sp. S1 was proliferated from 7·6 × 10(4) CFU g(-1) after 24 h to 4·6 × 10(8) CFU g(-1) after 96 h, which tallied with the maximum lipase activity as compared to control. Under submerged fermentation (SmF), Pseudomonas sp. S1 produced maximum lipase (49 IU ml(-1) ) using olive oil as substrate, while lipase production was 9·754 IU ml(-1) when Pseudomonas sp. S1 was grown on tributyrin. Optimum pH and temperature of the crude lipase was 7·0 and 50°C. Crude enzyme activity was 71·2% stable at 50°C for 360 min. Pseudomonas sp. S1 lipase was also stable in methanol showing 91·6% activity in the presence of 15% methanol, whereas 75·5 and 51·1% of activity were retained in the presence of 20 and 30% methanol, respectively. Thus, lipase produced by Pseudomonas sp. S1 is suitable for the production of biodiesel as well as treatment of oily waste water. This study presents the first report on the production of thermophilic organic solvent tolerant lipase using agro-industry waste in nonsterile solid state fermentation. Positive correlation between survival of Pseudomonas sp. S1 and lipase production under nonsterile solid state fermentation was established, which may emphasize the need to combine molecular tools and solid state fermentation in future studies. Our study brings new insights into the lipase production in cost-effective manner, which is an industrially relevant approach. © 2014 The Society for Applied Microbiology.

  15. Occurrence of multi-antibiotic resistant Pseudomonas spp. in drinking water produced from karstic hydrosystems.

    Science.gov (United States)

    Flores Ribeiro, Angela; Bodilis, Josselin; Alonso, Lise; Buquet, Sylvaine; Feuilloley, Marc; Dupont, Jean-Paul; Pawlak, Barbara

    2014-08-15

    Aquatic environments could play a role in the spread of antibiotic resistance genes by enabling antibiotic-resistant bacteria transferred through wastewater inputs to connect with autochthonous bacteria. Consequently, drinking water could be a potential pathway to humans and animals for antibiotic resistance genes. The aim of this study was to investigate occurrences of Escherichia coli and Pseudomonas spp. in drinking water produced from a karst, a vulnerable aquifer with frequent increases in water turbidity after rainfall events and run-offs. Water samples were collected throughout the system from the karstic springs to the drinking water tap during three non-turbid periods and two turbid events. E. coli densities in the springs were 10- to 1000-fold higher during the turbid events than during the non-turbid periods, indicating that, with increased turbidity, surface water had entered the karstic system and contaminated the spring water. However, no E. coli were isolated in the drinking water. In contrast, Pseudomonas spp. were isolated from the drinking water only during turbid events, while the densities in the springs were from 10- to 100-fold higher than in the non-turbid periods. All the 580 Pseudomonas spp. isolates obtained from the sampling periods were resistant (to between 1 and 10 antibiotics), with similar resistance patterns. Among all the Pseudomonas isolated throughout the drinking water production system, between 32% and 86% carried the major resistance pattern: ticarcillin, ticarcillin-clavulanic acid, cefsulodin, and/or aztreonam, and/or sulfamethoxazol-trimethoprim, and/or fosfomycin. Finally, 8 Pseudomonas spp. isolates, related to the Pseudomonas putida and Pseudomonas fluorescens species, were isolated from the drinking water. Thus, Pseudomonas could be involved in the dissemination of antibiotic resistance via drinking water during critical periods. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Isolation, molecular and biochemical characterization of oil degrading bacteria from contaminated soil at an oil refinery

    International Nuclear Information System (INIS)

    AL-Deeb, T.M.; Malkawi, H.I.

    2009-01-01

    Biodegradation using microorganisms is considered to be cost-effective and environmentally friendly treatment of oil-contaminated sites. Oil-biodegrading bacterial strains were isolated, identified and characterized from oil contaminated soil samples at oil refinery in Zarqa (Jordan). Thirty four bacterial isolates were grown on mineral salt media supplemented with crude oil, but 16 showed positive biodegradation of diesel. All the 34 bacterial isolates were characterized at the molecular and bio-chemical levels, and showed positive polymerase chain reaction (PCR) amplification product size of 1500 bp when 16s rDNA bacterial universal primers were used. Eighteen bacterial isolates showed positive PCR amplification product size of 150 bp specific for the genus Pseudomonas and 3 bacterial isolates showed positive amplification product size of 1500 bp specific for the genus Acinetobacter. Biochemical and physiological characterization performed on the 34 bacterial isolates revealed the presence of oil biodegrading bacterial genera and species of Pseudomonas Acidovorans, P. aeruginosa, P. vesicularis, Acinetobacter calcoaceticus, Ac. lowffii, Micro-ococcus luteus, M. varians, M. lylae, M. roseus, Alcaligenes denitrificians, Bacillus megaterium, Comamonas sp., Moralxella sp., Bordetella sp., P. putida, P. stutzeri and P. mallei. (au)

  17. Pseudomonas cichorii as the causal agent of midrib rot, an emerging disease of greenhouse-grown butterhead lettuce in Flanders.

    Science.gov (United States)

    Cottyn, Bart; Heylen, Kim; Heyrman, Jeroen; Vanhouteghem, Katrien; Pauwelyn, Ellen; Bleyaert, Peter; Van Vaerenbergh, Johan; Höfte, Monica; De Vos, Paul; Maes, Martine

    2009-05-01

    Bacterial midrib rot of greenhouse-grown butterhead lettuce (Lactuca sativa L. var. capitata) is an emerging disease in Flanders (Belgium) and fluorescent pseudomonads are suspected to play an important role in the disease. Isolations from infected lettuces, collected from 14 commercial greenhouses in Flanders, yielded 149 isolates that were characterized polyphasically, which included morphological characteristics, pigmentation, pathogenicity tests by both injection and spraying of lettuce, LOPAT characteristics, FAME analysis, BOX-PCR fingerprinting, 16S rRNA and rpoB gene sequencing, as well as DNA-DNA hybridization. Ninety-eight isolates (66%) exhibited a fluorescent pigmentation and were associated with the genus Pseudomonas. Fifty-five of them induced an HR+ (hypersensitive reaction in tobacco leaves) response. The other 43 fluorescent isolates were most probably saprophytic bacteria and about half of them were able to cause rot on potato tuber slices. BOX-PCR genomic fingerprinting was used to assess the genetic diversity of the Pseudomonas midrib rot isolates. The delineated BOX-PCR patterns matched quite well with Pseudomonas morphotypes defined on the basis of colony appearance and variation in fluorescent pigmentation. 16S rRNA and rpoB gene sequence analyses allowed most of the fluorescent isolates to be allocated to Pseudomonas, and they belonged to either the Pseudomonas fluorescens group, Pseudomonas putida group, or the Pseudomonas cichorii/syringae group. In particular, the isolates allocated to this latter group constituted the vast majority of HR+ isolates and were identified as P. cichorii by DNA-DNA hybridization. They were demonstrated by spray-inoculation tests on greenhouse-grown lettuce to induce the midrib rot disease and could be re-isolated from lesions of inoculated plants. Four HR+ non-fluorescent isolates associated with one sample that showed an atypical midrib rot were identified as Dickeya sp.

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

    Science.gov (United States)

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

    2016-01-04

    The Pseudomonas Genome Database (http://www.pseudomonas.com) is well known for the application of community-based annotation approaches for producing a high-quality Pseudomonas aeruginosa PAO1 genome annotation, and facilitating whole-genome comparative analyses with other Pseudomonas strains. To aid analysis of potentially thousands of complete and draft genome assemblies, this database and analysis platform was upgraded to integrate curated genome annotations and isolate metadata with enhanced tools for larger scale comparative analysis and visualization. Manually curated gene annotations are supplemented with improved computational analyses that help identify putative drug targets and vaccine candidates or assist with evolutionary studies by identifying orthologs, pathogen-associated genes and genomic islands. The database schema has been updated to integrate isolate metadata that will facilitate more powerful analysis of genomes across datasets in the future. We continue to place an emphasis on providing high-quality updates to gene annotations through regular review of the scientific literature and using community-based approaches including a major new Pseudomonas community initiative for the assignment of high-quality gene ontology terms to genes. As we further expand from thousands of genomes, we plan to provide enhancements that will aid data visualization and analysis arising from whole-genome comparative studies including more pan-genome and population-based approaches. © The Author(s) 2015. Published by Oxford University Press on behalf of Nucleic Acids Research.

  19. A Carbenicillin R Factor from Pseudomonas aeruginosa | van ...

    African Journals Online (AJOL)

    Of 64 carbenicillin-resistant Pseudomonas aeruginosa strains 40 transferred this resistance to Escherichia coli. R factor RP-638 isolated from Ps. aeruginosa strain 638 conferred resistance to ampicillin, carbenicillin, kanamycin, neomycin and tetracycline. This R factor was transferred at frequencies 01 10-7 to 10-4 between ...

  20. Impact of Ag and Al{sub 2}O{sub 3} nanoparticles on soil organisms: In vitro and soil experiments

    Energy Technology Data Exchange (ETDEWEB)

    Fajardo, C., E-mail: carmen.fajardo@vet.ucm.es [Facultad de Veterinaria, Universidad Complutense, 28040 Madrid (Spain); Saccà, M.L., E-mail: marialudovicasacca@pdi.ucm.es [Facultad de Veterinaria, Universidad Complutense, 28040 Madrid (Spain); Campus de Excelencia Internacional de Moncloa, 28040 Madrid (Spain); Costa, G., E-mail: costag@vet.ucm.es [Facultad de Veterinaria, Universidad Complutense, 28040 Madrid (Spain); Nande, M., E-mail: mnande@vet.ucm.es [Facultad de Veterinaria, Universidad Complutense, 28040 Madrid (Spain); Martin, M., E-mail: margamar@vet.ucm.es [Facultad de Veterinaria, Universidad Complutense, 28040 Madrid (Spain)

    2014-03-01

    In vitro analyses were conducted to assess the impact of Al{sub 2}O{sub 3} and Ag nanoparticles on two common soil bacteria, Bacillus cereus and Pseudomonas stutzeri. Al{sub 2}O{sub 3} nanoparticles did not show significant toxicity at any dose or time assayed, whereas exposure to 5 mg L{sup −1} Ag nanoparticles for 48 h caused bactericidal effects. Moreover, alterations at the morphological level were observed by transmission electron microscopy (TEM); Ag but not Al{sub 2}O{sub 3} nanoparticles evoked the entrance of B. cereus cells in an early sporulation stage and both nanoparticles penetrated P. stutzeri cells. At the molecular level, a dramatic increase (8.2-fold) in katB gene expression was found in P. stutzeri following Al{sub 2}O{sub 3} nanoparticles exposure, indicative of an oxidative stress-defence system enhancement in this bacterium. In the microcosm experiment, using two different natural soils, Al{sub 2}O{sub 3} or Ag nanoparticles did not affect the Caenorhabditis elegans toxicity endpoints growth, survival, or reproduction. However, differences in microbial phylogenetic compositions were detected by fluorescence in situ hybridization (FISH). The use of katB- and pykA-based sequences showed that the microbial transcriptional response to nanoparticle exposure decreased, suggesting a decrease in cellular activity. These changes were attributable to both the nanoparticles treatment and soil characteristics, highlighting the importance of considering the soil matrix on a case by case basis. - Highlights: • Al{sub 2}O{sub 3} or Ag NPs impact on bacteria was assessed at phenotypic and molecular level. • katB gene involved in oxidative-stress response was overexpressed in P. stutzeri following Al{sub 2}O{sub 3} NPs exposure. • A decrease in bacterial transcriptional response was detected in NPs-treated soils. • A soil-dependent response to specific NP treatment was observed. • In NPs-treated soils no acute toxic effects on C. elegans were found.

  1. Evaluation of pyrrolidonyl arylamidase for the identification of nonfermenting Gram-negative rods.

    Science.gov (United States)

    Bombicino, Karina A; Almuzara, Marisa N; Famiglietti, Angela M R; Vay, Carlos

    2007-01-01

    To evaluate the activity of pyrrolidonyl arylamidase (PYR) for the differentiation and identification of nonfermenting gram negative rods (NFGNR), 293 isolates were tested. A 24 h culture of each test organism was prepared. From this a 108-109 cfu/mL suspension was added to 0.25 mL of sterile physiologic solution. A PYR disk was then added and the test was incubated for 30 minutes at 35-37 degrees C, at environmental atmosphere. Reading was done by adding 1 drop of cinnamaldehyde reagent. Strains of Acinetobacter baumannii, Acinetobacter haemolyticus, Alcaligenes faecalis, Bergeyella zoohelcum, Bordetella bronchiseptica, Bordetella hinzii, Brevundimonas diminuta, Brevundimonas vesicularis, Brucella ovis, Brucella spp., Brucella suis, Burkholderia cepacia complex, Moraxella catarrhalis, Moraxella lacunata, Moraxella nonliquefaciens, Moraxella osloensis, Oligella ureolytica, Pseudomonas alcaligenes, Pseudomonas mendocina, Pseudomonas pseudoalcaligenes, Pseudomonas putida, Pseudomonas stutzeri, Pseudomonas Vb3, Psychrobacter phenylpyruvicus, and Stenotrophomonas maltophilia were PYR negative. On the other hand Achromobacter piechaudii, Achromobacter denitrificans, Achromobacter xylosoxidans, Burkholderia gladioli, Chryseobacterium gleum-indologenes, Comamonas testosroni, Cupriavidus pauculus, Delftia acidovorans, Elizabethkingia meningoseptica, Myroides spp., Ochrobactrum anthropi, Pseudomonas oryzihabitans, Ralstonia pickettii, Rhizobium radiobacter, Shewanella spp., Sphingobacterium multivorum, Sphingobacterium spiritivorum, and Weeksella virosa were PYR positive. Finally, Acinetobacter lwoffii, Pseudomonas aeruginosa, Pseudomonas fluorescens, Roseomonas spp., and Sphingomonas paucimobilis-parapaucimobilis were PYR variable. PYR testing should be considered as a useful tool to facilitate the identification of NFGNR.

  2. Monitoring of oil pollution at Gemsa Bay and bioremediation capacity of bacterial isolates with biosurfactants and nanoparticles.

    Science.gov (United States)

    El-Sheshtawy, H S; Khalil, N M; Ahmed, W; Abdallah, R I

    2014-10-15

    Fifteen crude oil-degrading bacterial isolates were isolated from an oil-polluted area in Gemsa Bay, Red Sea, Egypt. Two bacterial species showed the highest growth rate on crude oil hydrocarbons. From an analysis of 16S rRNA sequences, these isolates were identified as Pseudomonas xanthomarina KMM 1447 and Pseudomonas stutzeri ATCC 17588. Gas Chromatographic (GC) analysis of the crude oil remaining in the culture medium after one week at 30°C showed that the optimum biodegradation of crude petroleum oil was demonstrated at 50% in medium containing biosurfactant with two types of nanoparticles separately and two bacterial species. The complete degradation of some different members of polyaromatics and the percentage biodegradation of other polyaromatics increased in microcosm containing two different types of nanoparticles with biosurfactant after 7 days. In conclusion, these bacterial strains may be useful for the bioremediation process in the Gemsa Bay, Red Sea decreasing oil pollution in this marine ecosystem. Copyright © 2014 Elsevier Ltd. All rights reserved.

  3. Protective ventilation reduces Pseudomonas aeruginosa growth in lung tissue in a porcine pneumonia model.

    Science.gov (United States)

    Sperber, Jesper; Nyberg, Axel; Lipcsey, Miklos; Melhus, Åsa; Larsson, Anders; Sjölin, Jan; Castegren, Markus

    2017-08-31

    Mechanical ventilation with positive end expiratory pressure and low tidal volume, i.e. protective ventilation, is recommended in patients with acute respiratory distress syndrome. However, the effect of protective ventilation on bacterial growth during early pneumonia in non-injured lungs is not extensively studied. The main objectives were to compare two different ventilator settings on Pseudomonas aeruginosa growth in lung tissue and the development of lung injury. A porcine model of severe pneumonia was used. The protective group (n = 10) had an end expiratory pressure of 10 cm H 2 O and a tidal volume of 6 ml x kg -1 . The control group (n = 10) had an end expiratory pressure of 5 cm H 2 O and a tidal volume of 10 ml x kg -1 . 10 11 colony forming units of Pseudomonas aeruginosa were inoculated intra-tracheally at baseline, after which the experiment continued for 6 h. Two animals from each group received only saline, and served as sham animals. Lung tissue samples from each animal were used for bacterial cultures and wet-to-dry weight ratio measurements. The protective group displayed lower numbers of Pseudomonas aeruginosa (p protective group was unchanged (p protective ventilation with lower tidal volume and higher end expiratory pressure has the potential to reduce the pulmonary bacterial burden and the development of lung injury.

  4. Pseudomonas helleri sp. nov. and Pseudomonas weihenstephanensis sp. nov., isolated from raw cow's milk.

    Science.gov (United States)

    von Neubeck, M; Huptas, C; Glück, C; Krewinkel, M; Stoeckel, M; Stressler, T; Fischer, L; Hinrichs, J; Scherer, S; Wenning, M

    2016-03-01

    Analysis of the microbiota of raw cow's milk and semi-finished milk products yielded seven isolates assigned to the genus Pseudomonas that formed two individual groups in a phylogenetic analysis based on partial rpoD and 16S rRNA gene sequences. The two groups could be differentiated from each other and also from their closest relatives as well as from the type species Pseudomonas aeruginosa by phenotypic and chemotaxonomic characterization and average nucleotide identity (ANIb) values calculated from draft genome assemblies. ANIb values within the groups were higher than 97.3 %, whereas similarity values to the closest relatives were 85 % or less. The major cellular lipids of strains WS4917T and WS4993T were phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol; the major quinone was Q-9 in both strains, with small amounts of Q-8 in strain WS4917T. The DNA G+C contents of strains WS4917T and WS4993T were 58.08 and 57.30 mol%, respectively. Based on these data, strains WS4917T, WS4995 ( = DSM 29141 = LMG 28434), WS4999, WS5001 and WS5002 should be considered as representatives of a novel species of the genus Pseudomonas, for which the name Pseudomonas helleri sp. nov. is proposed. The type strain of Pseudomonas helleri is strain WS4917T ( = DSM 29165T = LMG 28433T). Strains WS4993T and WS4994 ( = DSM 29140 = LMG 28438) should be recognized as representing a second novel species of the genus Pseudomonas, for which the name Pseudomonas weihenstephanensis sp. nov. is proposed. The type strain of Pseudomonas weihenstephanensis is strain WS4993T ( = DSM 29166T = LMG 28437T).

  5. Pseudomonas Septic Arthritis | Thanni | Nigerian Journal of ...

    African Journals Online (AJOL)

    BACKGROUND: Septic arthritis due to pseudomonas species is unusual and when it occurs, there is often an underlying cause like immune depression, intravenous drug abuse or a penetrating injury. PATIENT AND METHOD: We report a case of pseudomonas septic arthritis complicating cannulation of a leg vein following ...

  6. Pseudomonas lactis sp. nov. and Pseudomonas paralactis sp. nov., isolated from bovine raw milk.

    Science.gov (United States)

    von Neubeck, Mario; Huptas, Christopher; Glück, Claudia; Krewinkel, Manuel; Stoeckel, Marina; Stressler, Timo; Fischer, Lutz; Hinrichs, Jörg; Scherer, Siegfried; Wenning, Mareike

    2017-06-01

    Five strains, designated WS 4672T, WS 4998, WS 4992T, WS 4997 and WS 5000, isolated from bovine raw milk formed two individual groups in a phylogenetic analysis. The most similar species on the basis of 16S rRNA gene sequences were Pseudomonas azotoformans IAM 1603T, Pseudomonas gessardii CIP 105469T and Pseudomonas libanensis CIP 105460T showing 99.7-99.6 % similarity. Using rpoD gene sequences Pseudomonas veronii LMG 17761T (93.3 %) was most closely related to strain WS 4672T and Pseudomonas libanensis CIP 105460T to strain WS 4992T (93.3 %). The five strains could be differentiated from their closest relatives and from each other by phenotypic and chemotaxonomic characterization and ANIb values calculated from draft genome assemblies. ANIb values of strains WS 4992T and WS4671T to the closest relatives are lower than 90 %. The major cellular polar lipids of both strains are phosphatidylethanolamine, phosphatidylglycerol, a phospholipid and diphosphatidylglycerol, and their major quinone is Q-9. The DNA G+C content of strains WS 4992T and WS 4672T were 60.0  and 59.7  mol%, respectively. Based on these genotypic and phenotypic traits two novel species of the genus Pseudomonas are proposed: Pseudomonas lactis sp. nov. [with type strain WS 4992T (=DSM 29167T=LMG 28435T) and the additional strains WS 4997 and WS 5000], and Pseudomonasparalactis sp. nov. [with type strain WS 4672T (=DSM 29164T=LMG 28439T) and additional strain WS 4998].

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

    Science.gov (United States)

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

    2009-07-31

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

  8. Antifungal activity and genetic diversity of selected Pseudomonas spp. from maize rhizosphere in Vojvodina

    Directory of Open Access Journals (Sweden)

    Jošić Dragana

    2012-01-01

    Full Text Available Antibiotic production by plant-associated microorganisms represents an environmentally compatible method of disease control in agriculture. However, a vide application of bacterial strains needs careful selection and genetic characterization. In this investigation, selected Pseudomonas strains were characterized by rep-PCR methods using ERIC and (GTG5 primers, and partial 16S rDNA sequence analysis. None of strains produced homoserine lactones (C4, C6, C8 as quorum sensing signal molecules. Very poor production of phenazines and no significant fungal inhibition was observed for PS4 and PS6 strains. High amount of phenazines were produced by Pseudomonas sp. strain PS2, which inhibited mycelial growth of 10 phytopatogenic fungi in percent of 25 (Verticillium sp. to 65 (Fusarium equiseti. Genetic characterization of the Pseudomonas sp. PS2 and evaluation of phenazines production, as the main trait for growth inhibition of phytopathogenic fungi, will allow its application as a biosafe PGPR for field experiments of plant disease control. [Projekat Ministarstva nauke Republike Srbije, br. III 46007: New indigenous bacterial isolates Lysobacter and Pseudomonas as an important sources of metabolites useful for biotechnology, plant growth stimulation and disease control: From isolates to inoculants

  9. Experimental Pseudomonas aeruginosa mediated rhino sinusitis in mink

    DEFF Research Database (Denmark)

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

    2017-01-01

    The nasal and sinus cavities in children may serve as reservoirs for microorganisms that cause recurrent and chronic lung infections. This study evaluates whether the mink can be used as an animal model for studying Pseudomonas aeruginosa mediated rhino-sinusitis since there is no suitable...... in the infected mink shows features of carbohydrate expression comparable to what has been described in the respiratory system after Pseudomonas aeruginosa infection in humans. It is suggested that the mink is suitable for studying Pseudomonas aeruginosa mediated rhino-sinusitis....

  10. The presence of INA proteins on the surface of single cells of Pseudomonas syringae R10.79 isolated from rain

    Science.gov (United States)

    Šantl-Temkiv, Tina; Ling, Meilee; Holm, Stine; Finster, Kai; Boesen, Thomas

    2016-04-01

    One of the important open questions in atmospheric ice nucleation is the impact of bioaerosols on the ice content of mix phase clouds (DeMott and Prenni 2010). Biogenic ice nuclei have a unique capacity of facilitating ice formation at temperatures between -1 and -10 °C. The model biogenic ice nuclei are produced by a few species of plant-surface bacteria, such as Pseudomonas syringae, that are commonly transported through the atmosphere. These bacterial species have highly specialized proteins, the so-called ice nucleation active (INA) proteins, which are exposed at the outer membrane surface of the cell where they promote ice particle formation. The mechanisms behind the onset of INA protein synthesis in single bacterial cells are not well understood. We performed a laboratory study in order to (i) investigate the presence of INA proteins on single bacterial cells and (ii) understand the conditions that induce INA protein production. We previously isolated an INA-positive strain of Pseudomonas syringae from rain samples collected in Denmark. Bacterial cells initiated ice nucleation activity at temperatures ≤-2°C and the cell fragments at temperatures ≤-8°C (Šantl-Temkiv et al 2015). We determined the amino-acid sequence of the INA protein and used the sequence to produce custom-made antibodies (GenScript, Germany). These antibodies were used to specifically stain and visualize the INA protein on the surfaces of single cells, which can then be quantified by a technique called flow cytometry. The synthesis of INA proteins by individual cells was followed during a batch growth experiment. An unusually high proportion of cells that were adapting to the new conditions prior to growth produced INA proteins (~4.4% of all cells). A smaller fraction of actively growing cells was carrying INA proteins (~1.2 % of all cells). The cells that stopped growing due to unfavorable conditions had the lowest fraction of cells carrying INA proteins (~0.5 % of all cells). To

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

    Directory of Open Access Journals (Sweden)

    Willcox MD

    2012-06-01

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

  12. Pseudomonas wadenswilerensis sp. nov. and Pseudomonas reidholzensis sp. nov., two novel species within the Pseudomonas putida group isolated from forest soil.

    Science.gov (United States)

    Frasson, David; Opoku, Michael; Picozzi, Tara; Torossi, Tanja; Balada, Stefanie; Smits, Theo H M; Hilber, Urs

    2017-08-01

    Within the frame of a biotechnological screening, we isolated two Pseudomonas strains from forest soil. 16S rRNA gene sequence analysis indicated that strain CCOS 864T shared 99.8 % similarity with Pseudomonas donghuensis HYST, while strain CCOS 865T shared 99.0 % similarity with Pseudomonas putida DSM 291T and lower similarity with other P. putida group type strains. Based on multilocus sequence analysis, the two strains were genotypically distinct from each other, each forming a separate clade. Strains CCOS 864T and CCOS 865T were Gram-stain-negative, motile and rod-shaped, growing at a temperature range of 4-37 °C. Strain CCOS 864T could be phenotypically distinguished from P. putida group species by the combination of gelatinase-positive reaction and positive growth on N-acetyl-d-glucosamine, p-hydroxyphenylacetic acid and inosine but lack of fluorescein production on King's B medium, while strain CCOS 865T could be distinguished from P. putida group species by the combination of positive growth with saccharic acid and negative growth with p-hydroxyphenylacetic acid and l-pyroglutamic acid. The major polar lipid for both strains was phosphatidylethanolamine; the major quinone was ubiquinone Q-9. DNA-DNA hybridization and average nucleotide identities confirmed the novel species status for the two strains. The DNA G+C contents of CCOS 864T and CCOS 865T were 62.1 and 63.8 mol%, respectively. The phenotypic, phylogenetic and DNA-DNA relatedness data support the suggestion that CCOS 864T and CCOS 865T represent two novel Pseudomonas species. The names Pseudomonas wadenswilerensis sp. nov. (type strain CCOS 864T=LMG 29327T) and Pseudomonas reidholzensis sp. nov. (type strain CCOS 865T=LMG 29328T) are proposed.

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

    DEFF Research Database (Denmark)

    Johansen, Helle Krogh; Gøtzsche, Peter C

    2015-01-01

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

  14. Distribution, diversity, and activity of antibiotic-producing Pseudomonas spp.

    NARCIS (Netherlands)

    Souza, de J.T.

    2002-01-01

    Bacteria of the genus Pseudomonas are potential biocontrol agents of plant diseases caused by various fungi and oomycetes. Antibiotic production is an important trait responsible for the activity of several Pseudomonas

  15. Matrix evaluation for Pseudomonas spp. immobilisation in phenol bioremediation

    Directory of Open Access Journals (Sweden)

    Leonel Chitiva Urbina

    2003-07-01

    Full Text Available Pseudomonas spp. were cultivated in a free cell suspension and also immobilised in three different matrices to observe the influence of a contaminant like phenol on degradation velocity and compare each one's results. Polyurethane polymers, alginate (Manohar et al, 2001 and a mixture of alginate and polyvinyl alcohol (Doria et al, 2002 were selected and tested as matrices; all of them proved viable as matrices for cell immobilisation. Pseudomonas were cultivated in an initial 10 cfu/ml concentration in each one of the matrices for comparison purposes and in a medium without matrix; all mediums were supplemented with a minimum salt medium and 200 ppm phenol. A removal time of 23 days was observed in the medium without matrix, 15 days in the polyurethane matrix and 7 days in the alginate matrices. Improved removal times were observed in all matrices when compared to the free cell suspension.

  16. Pseudomonas Lipopeptide Biosurfactants

    DEFF Research Database (Denmark)

    Bonnichsen, Lise

    Pseudomonas lipopetide biosurfactants are amphiphilic molecules with a broad range of natural functions. Due to their surface active properties, it has been suggested that Pseudomonas lipopetides potentially play a role in biodegradation of hydrophobic compounds and have essential functions...... lipopetide biosurfactants in pollutant biodegradation and natural roles in biofilm formation. The work presented is a combination of environmental microbiology and exploiting genetic manipulation of pure cultures to achieve insightinto the effects and mechanisms of lipopeptides on microbial processes...

  17. Pseudomonas salina sp. nov., isolated from a salt lake.

    Science.gov (United States)

    Zhong, Zhi-Ping; Liu, Ying; Hou, Ting-Ting; Liu, Hong-Can; Zhou, Yu-Guang; Wang, Fang; Liu, Zhi-Pei

    2015-09-01

    A Gram-staining-negative, facultatively aerobic bacterium, strain XCD-X85(T), was isolated from Xiaochaidan Lake, a salt lake (salinity 9.9%, w/v) in Qaidam basin, Qinghai province, China. Its taxonomic position was determined by using a polyphasic approach. Cells of strain XCD-X85(T) were non-endospore-forming rods, 0.4-0.6 μm wide and 1.0-1.6 μm long, and motile by means of a single polar flagellum. Strain XCD-X85(T) was catalase- and oxidase-positive. Growth was observed in the presence of 0-12.0% (w/v) NaCl (optimum, 1.0-2.0%) and at 4-35 °C (optimum, 25-30 °C) and pH 6.5-10.5 (optimum, pH 8.0-8.5). Strain XCD-X85(T) contained (>10%) summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c), C12 : 0, C16 : 0 and summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c) as the predominant fatty acids. The major respiratory quinone was ubiquinone 9 (Q-9). The major polar lipids were phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol. The DNA G+C content was 57.4 mol%. Phylogenetic trees based on 16S rRNA gene sequences showed that strain XCD-X85(T) was associated with the genus Pseudomonas, and showed highest 16S rRNA gene sequence similarities to Pseudomonas pelagia CL-AP6(T) (99.0%) and Pseudomonas bauzanensis BZ93(T) (96.8%). DNA-DNA relatedness of strain XCD-X85T to P. pelagia JCM 15562(T) was 19 ± 1%. On the basis of the data presented above, it is concluded that strain XCD-X85(T) represents a novel species of the genus Pseudomonas, for which the name Pseudomonas salina sp. nov. is proposed. The type strain is XCD-X85(T) ( = CGMCC 1.12482(T) = JCM 19469(T)).

  18. Denitrification by Rhizobium meliloti

    Energy Technology Data Exchange (ETDEWEB)

    Rosen, A

    1996-10-01

    Rhizobium meliloti strains were investigated for their denitrification activity as free-living cells and in nodules on lucerne (Medicago sativa) roots. They were also investigated for presence of nitrous oxide reductase (nos) activity and for genes using a nosZ probe derived from the Pseudomonas stutzeri. To decide whether R. meliloti strains used as inoculants contribute to the total denitrification activity in a lucerne ley, strains with different denitrifying capacities were used in field and laboratory experiments. The nitrate reduction activity of R. meliloti during anaerobic respiration was compared with that of a strain of Pseudomonas aeruginosa. A great diversity in the denitrification activity was found within strains of R. meliloti, and four of thirteen investigated strains showed an obvious denitrification activity. Two denitrifying bacteria were used as references, one strain each of Bradyrhizobium japonicum and P. aeruginosa. All but one of the R. meliloti strains hybridized to the PstI-fragment of the nosZ-gene from P. stutzeri. Two sizes of the hybridizing fragment, 5 and 7 kb, were noticed. Nos activity was only shown in three R. meliloti strains, and these were all characterized by a high denitrification activity. The potential denitrification activity was about 20, 40, and 80 times higher than the actual denitrification activity for lucerne, fallow, and grass, respectively. The potential denitrification activity was almost the same in lucerne and grass planted soils. Compared with the unplanted soil, the presence of lucerne roots in the soil increased the actual denitrification activity, while roots of both plant species, grass and lucerne, increased the potential denitrification activity in the soil. 32 refs, 7 figs, 1 tab

  19. Methylphosphonate metabolism by Pseudomonas sp. populations contributes to the methane oversaturation paradox in an oxic freshwater lake.

    Science.gov (United States)

    Wang, Qian; Dore, John E; McDermott, Timothy R

    2017-06-01

    The 'CH 4 oversaturation paradox' has been observed in oxygen-rich marine and lake waters, and viewed to significantly contribute to biosphere cycling of methane, a potent greenhouse gas. Our study focused on the intriguing well-defined pelagic methane enriched zone (PMEZ) in freshwater lakes. Spiking Yellowstone Lake PMEZ samples with 13 C-labeled potential methanogenesis substrates found only 13 C-methylphosphonate (MPn) resulted in 13 CH 4 generation. In 16S rRNA gene Illumina libraries, four Pseudomonas sp. operational taxonomic units surprisingly accounted for ∼11% abundance in the PMEZ community. Pseudomonas sp. isolates were also obtained from MPn enrichments with PMEZ water; they were most aggressive in MPn metabolism and their 16S rRNA gene sequences matched 35% of the Illumina PMEZ Pseudomonas reads. Further, two key genes encoding C-P lyase (phnJL, an important enzyme for dealkylation of MPn), were only amplifiable from PMEZ DNA and all PCR generated phnJL clones matched those of the Pseudomonas sp. isolates. Notably, methanogen 16S rRNA signatures were absent in all Illumina libraries and mcrA was not detected via PCR. Collectively, these observations are consistent with the conclusion that MPn metabolism contributes significantly to CH 4 oversaturation in Yellowstone Lake and likely other oxic freshwater lake environments, and that Pseudomonas sp. populations are critical participants. © 2017 Society for Applied Microbiology and John Wiley & Sons Ltd.

  20. Efficacy of Calcium-EDTA as an Inhibitor for Metallo-β-Lactamase in a Mouse Model of Pseudomonas aeruginosa Pneumonia▿

    OpenAIRE

    Aoki, Nobumasa; Ishii, Yoshikazu; Tateda, Kazuhiro; Saga, Tomoo; Kimura, Soichiro; Kikuchi, Yoshiaki; Kobayashi, Tetsuo; Tanabe, Yoshinari; Tsukada, Hiroki; Gejyo, Fumitake; Yamaguchi, Keizo

    2010-01-01

    In this study, we have evaluated the efficacy of calcium-EDTA (Ca-EDTA) as an inhibitor of bacterial metalloenzymes, such as metallo-β-lactamase (MBL) and other proteases, in a mouse model of Pseudomonas aeruginosa pneumonia. The simultaneous presence of Ca-EDTA (32 μg/ml) reduced the MICs of imipenem (IPM) in all MBL-producing P. aeruginosa isolates (IMP-1, -2, -7, and -10 and VIM-2) but not non-MBL-producing strains. In the pneumonia model, mice were intranasally infected with MBL-producing...

  1. Quorum quenching by an N-acyl-homoserine lactone acylase from Pseudomonas aeruginosa PAO1

    NARCIS (Netherlands)

    Sio, CF; Otten, LG; Cool, RH; Diggle, SP; Braun, PG; Daykin, M; Camara, M; Williams, P; Quax, WJ; Bos, R

    The virulence of the opportunistic human pathogen Pseudomonas aeruginosa PAO1 is controlled by an N-acyl-homoserine lactone (AHL)-dependent quorum-sensing system. During functional analysis of putative acylase genes in the P. aeruginosa PAO1 genome, the PA2385 gene was found to encode an acylase

  2. Biosynthesis and regulation of cyclic lipopeptides in Pseudomonas fluorescens

    NARCIS (Netherlands)

    Bruijn, de I.

    2009-01-01

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

  3. Insights into the mechanisms of Promysalin, a secondary metabolite with genus-specific antibacterial activity against Pseudomonas

    Science.gov (United States)

    Promysalin, a secondary metabolite produced by Pseudomonas putida RW10S1, has antibacterial activity against a wide variety of Pseudomonas sp., including both human and plant pathogens. Promysalin induces swarming and biofilm formation in the producing species, and inhibits growth of susceptible sp...

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

    Science.gov (United States)

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

  5. Effect of Iron Availability on Induction of Systemic Resistance to Fusarium Wilt of Chickpea by Pseudomonas spp.

    Science.gov (United States)

    Saikia, Ratul; Srivastava, Alok K; Singh, Kiran; Arora, Dilip K; Lee, Min-Woong

    2005-03-01

    Selected isolates of Pseudomonas fluorescens (Pf4-92 and PfRsC5) and P. aeruginosa (PaRsG18 and PaRsG27) were examined for growth promotion and induced systemic resistance against Fusarium wilt of chickpea. Significant increase in plant height was observed in Pseudomonas treated plants. However, plant growth was inhibited when isolates of Pseudomonas were used in combination with Fusarium oxysporum f. sp. ciceri (FocRs1). It was also observed that the Pseudomonas spp. was colonized in root of chickpea and significantly suppressed the disease in greenhouse condition. Rock wool bioassay technique was used to study the effect of iron availability on the induction of systemic resistance to Fusarium wilt of chickpea mediated by the Pseudomonas spp. All the isolates of Pseudomonas spp. showed greater disease control in the induced systemic resistance (ISR) bioassay when iron availability in the nutrient solution was low. High performance liquid chromatography (HPLC) analysis indicated that all the bacterial isolates produced more salicylic acid (SA) at low iron (10µM EDDHA) than high iron availability (10µFe(3+) EDDHA). Except PaRsG27, all the three isolates produced more pseudobactin at low iron than high iron availability.

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

    African Journals Online (AJOL)

    Using the BMM medium containing 100 mg/L of reactive brilliant red X-3B, a decolorizing bacterium with higher decolorization activity was isolated and it showed a decolorization zone of 10 mm; this decolorizing bacterium was identified as Pseudomonas putida WLY based on physiological and biochemical characteristics ...

  7. Biodegradation of chlorpyrifos by bacterial genus Pseudomonas.

    Science.gov (United States)

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

    2016-02-01

    Chlorpyrifos is an organophosphorus pesticide commonly used in agriculture. It is noxious to a variety of organisms that include living soil biota along with beneficial arthropods, fish, birds, humans, animals, and plants. Exposure to chlorpyrifos may cause detrimental effects as delayed seedling emergence, fruit deformities, and abnormal cell division. Contamination of chlorpyrifos has been found about 24 km from the site of its application. There are many physico-chemical and biological approaches to remove organophosphorus pesticides from the ecosystem, among them most promising is biodegradation. The 3,5,6-trichloro-2-pyridinol (TCP) and diethylthiophosphate (DETP) as primary products are made when chlorpyrifos is degraded by soil microorganisms which further break into nontoxic metabolites as CO(2), H(2)O, and NH(3). Pseudomonas is a diversified genus possessing a series of catabolic pathways and enzymes involved in pesticide degradation. Pseudomonas putida MAS-1 is reported to be more efficient in chlorpyrifos degradation by a rate of 90% in 24 h among Pseudomonas genus. The current review analyzed the comparative potential of bacterial species in Pseudomonas genus for degradation of chlorpyrifos thus, expressing an ecofriendly approach for the treatment of environmental contaminants like pesticides. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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

    Science.gov (United States)

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

  9. Selenium recovery from kiln powder of cement manufacturing by chemical leaching and bioreduction.

    Science.gov (United States)

    Soda, S; Hasegawa, A; Kuroda, M; Hanada, A; Yamashita, M; Ike, M

    2015-01-01

    A novel process by using chemical leaching followed by bacterial reductive precipitation was proposed for selenium recovery from kiln powder as a byproduct of cement manufacturing. The kiln powder at a slurry concentration of 10 w/v% with 0.25 M Na2CO3 at 28°C produced wastewater containing about 30 mg-Se/L selenium. The wastewater was diluted four-fold and adjusted to pH 8.0 as preconditioning for bioreduction. A bacterial strain Pseudomonas stutzeri NT-I, capable of reducing selenate and selenite into insoluble elemental selenium, could recover about 90% selenium from the preconditioned wastewater containing selenium of 5 mg-Se/L when supplemented with lactate or glycerol. The selenium concentrations in the treated wastewater were low around the regulated effluent concentration of 0.1 mg-Se/L in Japan.

  10. Denitrification of nitrate waste solutions

    International Nuclear Information System (INIS)

    Michaels, S.L.; Michel, R.C.; Terpandjian, P.D.; Vora, J.N.

    1976-01-01

    Bacterial denitrification by Pseudomonas Stutzeri has been chosen as the method for removing nitrate from the effluent stream of the Y-12 uranium purification process. A model was developed to predict bacterial growth and carbon and nitrate depletion during the induction period and steady state operation. Modification of analytical procedures and automatic control of the pH in the reactor are recommended to improve agreement between the prediction of the model and experimental data. An initial carbon-to-nitrogen (C/N) mass ratio of 1.4-1.5 insures adequate population growth during the induction period. Further experiments in batch reactors and in steady state flow reactors are recommended to obtain more reliable kinetic rate constants

  11. NCBI nr-aa BLAST: CBRC-TGUT-10-0002 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-TGUT-10-0002 gb|AAX58577.1| HrpW [Pseudomonas viridiflava] gb|AAX58585.1| HrpW [Pseudomonas... viridiflava] gb|AAX58587.1| HrpW [Pseudomonas viridiflava] AAX58577.1 0.035 31% ...

  12. Inhibition of Pseudomonas aeruginosa elastase and Pseudomonas keratitis using a thiol-based peptide.

    OpenAIRE

    Burns, F R; Paterson, C A; Gray, R D; Wells, J T

    1990-01-01

    Pseudomonas aeruginosa elastase is a zinc metalloproteinase which is released during P. aeruginosa infections. Pseudomonas keratitis, which occurs following contact lens-induced corneal trauma, can lead to rapid, liquefactive necrosis of the cornea. This destruction has been attributed to the release of both host-derived enzymes and the bacterial products P. aeruginosa elastase, alkaline protease, exotoxin A, and lipopolysaccharide endotoxin. A synthetic metalloproteinase inhibitor, HSCH2 (DL...

  13. Pseudomonas aeruginosa, an emerging pathogen among burn patients in Kurdistan Province, Iran.

    Science.gov (United States)

    Kalantar, Enayat; Taherzadeh, Shadi; Ghadimi, Tayeb; Soheili, Fariborz; Salimizand, Heiman; Hedayatnejad, Alireza

    2012-05-01

    This study was conducted to determine the incidence of Pseudomonas aeruginosa infections among burn patients at Tohid Hospital, Iran. A total of 176 clinical specimens were obtained from 145 burn patients admitted to the burn unit of Tohid Hospital to detect the presence of P. aeruginosa. Antimicrobial susceptibility testing was conducted to detect extended spectrum beta-lactamase (ESBL) producing P. aeruginiosa using Clinical and Laboratory Standards Institute guidelines with the double disc synergy test (DDST). A polymerase chain reaction was used to detect PER-1 and OXA-10 among the isolates. The mean age, total body surface area and length of hospital stay among patients were 29 years, 37.7%, and 10 days, respectively. Kerosene was the commonest cause of burn (60%), followed by gas (30%). During the study, P. aeruginosa was detected in 100 isolates. The antibiotics they were most commonly resistant to were cefotaxime, ceftriaxone and ciprofloxacin. Of the 100 P. aeroginusa isolates, 28% were positive for ESBL production with the DDST, 48% and 52% were PER-1 and OXA-10 producers, respectively. The high frequency of PER-1 and OXA-10 producers at this hospital is of concern considering their potential spread among burn patients.

  14. 21 CFR 866.3415 - Pseudomonas spp. serological reagents.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Pseudomonas spp. serological reagents. 866.3415... (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3415 Pseudomonas spp. serological reagents. (a) Identification. Pseudomonas spp. serological reagents are devices that...

  15. Control of spoiler Pseudomonas spp. on fresh cut vegetables by neutral electrolyzed water.

    Science.gov (United States)

    Pinto, Loris; Ippolito, Antonio; Baruzzi, Federico

    2015-09-01

    In the present study, we evaluated the antimicrobial activity of neutral electrolyzed water (NEW) against 14 strains of spoilage Pseudomonas of fresh cut vegetables under cold storage. The NEW, produced from solutions of potassium and sodium chloride, and sodium bicarbonate developed up to 4000 mg/L of free chlorine, depending on the salt and relative concentration used. The antimicrobial effect of the NEW was evaluated against different bacterial strains at 10(5) cells/ml, with different combinations of free chlorine concentration/contact time; all concentrations above 100 mg/L, regardless of the salt used, were found to be bactericidal already after 2 min. When catalogna chicory and lettuce leaves were dipped for 5 min in diluted NEW, microbial loads of mesophilic bacteria and Enterobacteriaceae were reduced on average of 1.7 log cfu/g. In addition, when lettuce leaves were dipped in a cellular suspension of the spoiler Pseudomonas chicorii I3C strain, diluted NEW was able to reduce Pseudomonas population of about 1.0 log cfu/g. Thanks to its high antimicrobial activity against spoilage microorganisms, and low cost of operation, the application of cycles of electrolysis to the washing water looks as an effective tool in controlling fresh cut vegetable microbial spoilage contamination occurring during washing steps. Copyright © 2015 Elsevier Ltd. All rights reserved.

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

    Science.gov (United States)

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

    2013-01-01

    Brazilian freshwater fish caught from large drainages like the River Amazon represent a million ton market in expansion, which is of enormous importance for export to other continents as exotic seafood. A guarantee of bacteriological safety is required for international exports that comprise a set of different bacteria but not any Pseudomonas. However, diarrhoea, infections and even septicaemia caused by some Pseudomonas species have been reported, especially in immune-depressed patients. In this work we have employed PCR-based methodology for identifying Pseudomonas species in commercial fish caught from two different areas within the Amazon basin. Most fish caught from the downstream tributary River Tapajòs were contaminated by five different Pseudomonas species. All fish samples obtained from the River Negro tributary (Manaus markets) contained Pseudomonas, but a less diverse community with only two species. The most dangerous Pseudomonas species for human health, P. aeruginosa, was not found and consumption of these fish (from their Pseudomonas content) can be considered safe for healthy consumers. As a precautionary approach we suggest considering Pseudomonas in routine bacteriological surveys of imported seafood. PMID:24065035

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

    African Journals Online (AJOL)

    The test media were Muller-Hinton agar and eosin methylene blue (EMB) agar. In this research Pseudomonas aeruginosa which was isolated from patients wounds was examined with levels of alternating and direct current (AC and DC) electrical stimulation (1.5V, 3.5V, 5.5V and 10V) to see if these currents could inhibit P.

  18. 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.

  19. Ocorrência de linhagens de Pseudomonas aeruginosa cloro resistentes em águas de diferentes origens - DOI: 10.4025/actascibiolsci.v29i3.488 Ocurrence of chlorine resistant strains of Pseudomonas aeruginosa from different water sources - DOI: 10.4025/actascibiolsci.v29i3.488

    Directory of Open Access Journals (Sweden)

    Ulrich Vasconcelos

    2007-12-01

    Full Text Available Pseudomonas aeruginosa é conhecida por sua versatilidade metabólica e extrema capacidade de adaptação a diferentes ambientes, inclusive aquáticos. Para desinfecção de águas, o cloro e agentes que contêm cloro continuam sendo os mais usados no mundo. O objetivo deste trabalho foi avaliar a resistência ao cloro de linhagens de P. aeruginosa, isoladas de amostras de águas de diversos ambientes. Foram testados diferentes tempos de contato (1, 5, 10, 20, 30 e 40 minutos e soluções aquosas de cloro, com concentrações definidas com base na legislação vigente no país para água potável: 0,5; 1,0 e 2,0 ppm. O teste de resistência ao cloro foi desenvolvido por meio da exposição direta das bactérias às soluções. Os resultados revelaram que P. aeruginosa, isoladas de diferentes fontes de água, têm a habilidade de sobreviver a diferentes concentrações de cloro. Na concentração de 1 ppm, a maioria das linhagens não foi inibida. As linhagens mais resistentes ao cloro também apresentaram relação de multirresistência à maioria dos antibióticos testados.The nutritional versatility and the adaptability of Pseudomonas aeruginosa to different environments, including water, are well known. Chlorine and other chlorine agents are used as water disinfecting all around the world. The aim of this work was to evaluate the possible chlorine resistance amongst P. aeruginosa strains isolated from different aquatic sources by using different contact time (1, 5, 10, 20, 30 and 40 minutes in solutions with known chlorine concentrations according current legislation in the country to potable water: 0.5; 1.0 and 2.0 ppm. The chlorine resistance test was done by direct exposure of P. aeruginosa under a solution with known chlorine concentration. Results showed that P. aeruginosa strains isolated from different aquatic sources are able to survive in different chlorine concentrations. At 1 ppm, most of them were not inhibited. It was also

  20. Antibiotics Susceptibility Pattern of Pseudomonas aeruginosa ...

    African Journals Online (AJOL)

    ABSTRACT: This work investigated the prevalence and antibiotics sensitivity of Pseudomonas aeruginosa isolated from ... skin triggers coagulation and an acute inflammatory response ... agents with anti-pseudomonal activity, life-threatening.

  1. Characterization of an extracellular lipase by Pseudomonas koreensis BK-L07 isolated from soil.

    Science.gov (United States)

    Anbu, Periasamy

    2014-01-01

    Screening using spirit blue agar revealed that strain BK-L07 had the highest lipase activity. Furthermore, the isolated strain was identified as Pseudomonas sp. based on morphological, physiological, biochemical, and molecular analyses. The 16S rRNA gene sequence of strain BK-L07 shared a high similarity with that of Pseudomonas koreensis (99%). The nutritional conditions and physicochemical properties were influenced by P. koreensis BK-L07. The maximum lipase production was obtained in tryptic soy broth medium at pH 8.0 and a temperature of 25°C after 36 hr of incubation. In addition, the lipase activity was determined using different carbon sources and lipase inducers. The lipase production was greatest when 1% maltose was used as the carbon source and olive oil was used as the lipase inducer. The lipase production was significantly increased approximately threefold in the optimized medium when compared with the original medium. Further, the lipase was purified by ammonium sulfate precipitation and gel filtration chromatography with a purification yield of 10.8%. The molecular mass of lipase was 45 kDa. The optimum temperature and pH were 40°C and 8.0, respectively. The enzyme was stable up to 50°C and at pH from 7 to 9. In addition, the enzyme activity was stimulated by MgSO4 and completely inhibited by ethylenediamine tetraacetic acid (EDTA), indicating the metalloenzyme type. The lipase activity was toward medium to long chain length of fatty acids (C10 to C18). Supplemental materials are available for this article. Go to the publisher's online edition of Preparative Biochemistry and Biotechnology to view the supplemental file.

  2. Comparative activities of ciprofloxacin, ticarcillin, and tobramycin against experimental Pseudomonas aeruginosa pneumonia.

    OpenAIRE

    Schiff, J B; Small, G J; Pennington, J E

    1984-01-01

    The therapeutic efficacy of ciprofloxacin, an investigational quinoline derivative, was compared with those of ticarcillin and tobramycin in guinea pigs with experimental Pseudomonas aeruginosa pneumonia. Guinea pigs challenged with tracheal instillations of 10(8) CFU of P. aeruginosa developed acute pneumonia, for which survival rates were: controls, 0%; ticarcillin treatment, 37%; ciprofloxacin treatment, 57%; and tobramycin treatment, 69%. Intrapulmonary killing of P. aeruginosa was greate...

  3. Pseudomonas-follikulitis efter badning i spabad

    DEFF Research Database (Denmark)

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

    2012-01-01

    . We describe a 23-year-old healthy woman who developed a pustular rash and general malaise after using a spa bath contaminated with Pseudomonas aeruginosa. Bacterial culture from a pustule confirmed Pseudomonas folliculitis and the patient was treated with ciprofloxacin with rapid good effect....

  4. Chemical sanitizers to control biofilms formed by two Pseudomonas species on stainless steel surface

    Directory of Open Access Journals (Sweden)

    Danila Soares Caixeta

    2012-03-01

    Full Text Available The biofilm formation of Pseudomonas aeruginosa and Pseudomonas fluorescens on AISI 304 stainless steel in the presence of reconstituted skim milk under different temperatures was conducted, and the potential of three chemical sanitizers in removing the mono-species biofilms formed was compared. Pseudomonas aeruginosa cultivated in skim milk at 28 °C presented better growth rate (10.4 log CFU.mL-1 when compared with 3.7 and 4.2 log CFU.mL-1 for P. aeruginosa and P. fluorescens cultivated at 7 °C, respectively. Pseudomonas aeruginosa formed biofilm when cultivated at 28 °C. However, only the adhesion of P. aeruginosa and P. fluorescens was observed when incubated at 7 °C. The sodium dichloroisocyanurate was the most efficient sanitizer in the reduction of the adhered P. aeruginosa cells at 7 and 28 °C and those on the biofilm, respectively. The hydrogen peroxide was more effective in the reduction of adhered cells of P. fluorescens at 7 °C.

  5. The Pseudomonas Quinolone Signal (PQS)

    DEFF Research Database (Denmark)

    Sams, Thomas; Baker, Ysobel; Hodgkinson, James

    2015-01-01

    Pseudomonas aeruginosa is an opportunistichuman pathogen that routinely appears near the top ofpublic health threat lists worldwide. P. aeruginosa causes in-fections by secreting a wealth of exceptionally active exo-products, leading to tissue damage. The synthesis of manyof these virulence factors...

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

    NARCIS (Netherlands)

    Braun, P; Bitter, W; Tommassen, J

    2000-01-01

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

  7. 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...

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

    DEFF Research Database (Denmark)

    Bailey, Susan; Hinz, Aaron; Kassen, Rees

    2014-01-01

    Conventional wisdom holds that synonymous mutations, nucleotide changes that do not alter the encoded amino acid, have no detectable effect on phenotype or fitness. However, a growing body of evidence from both comparative and experimental studies suggests otherwise. Synonymous mutations have been...... shown to impact gene expression, protein folding and fitness, however, direct evidence that they can be positively selected, and so contribute to adaptation, is lacking. Here we report the recovery of two beneficial synonymous single base pair changes that arose spontaneously and independently...... in an experimentally evolved population of Pseudomonas fluorescens. We show experimentally that these mutations increase fitness by an amount comparable to non-synonymous mutations and that the fitness increases stem from increased gene expression. These results provide unequivocal evidence that synonymous mutations...

  9. Pseudomonas fluvialis sp. nov., a novel member of the genus Pseudomonas isolated from the river Ganges, India.

    Science.gov (United States)

    Sudan, Sarabjeet Kour; Pal, Deepika; Bisht, Bhawana; Kumar, Narender; Chaudhry, Vasvi; Patil, Prabhu; Sahni, Girish; Mayilraj, Shanmugam; Krishnamurthi, Srinivasan

    2018-01-01

    A bacterial strain, designated ASS-1 T , was isolated and identified from a sediment sample of the river Ganges, Allahabad, India. The strain was Gram-stain-negative, formed straw-yellow pigmented colonies, was strictly aerobic, motile with a single polar flagellum, and positive for oxidase and catalase. The major fatty acids were C16 : 1ω7c/ 16 : 1 C16 : 1ω6c, C18 : 1ω7c and C16 : 0. Sequence analysis based on the 16S rRNA gene revealed that strain ASS-1 T showed high similarity to Pseudomonas guguanensis CC-G9A T (98.2 %), Pseudomonas alcaligenes ATCC 14909 T (98.2 %), Pseudomonas oleovorans DSM 1045 T (98.1 %), Pseudomonas indolxydans IPL-1 T (98.1 %) and Pseudomonas toyotomiensis HT-3 T (98.0 %). Analysis of its rpoB and rpoD housekeeping genes confirmed its phylogenetic affiliation and showed identities lower than 93 % with respect to the closest relatives. Phylogenetic analysis based on the 16S rRNA, rpoB, rpoD genes and the whole genome assigned it to the genus Pseudomonas. The results of digital DNA-DNA hybridization based on the genome-to-genome distance calculator and average nucleotide identity revealed low genome relatedness to its close phylogenetic neighbours (below the recommended thresholds of 70 and 95 %, respectively, for species delineation). Strain ASS-1 T also differed from the related strains by some phenotypic characteristics, i.e. growth at pH 5.0 and 42 °C, starch and casein hydrolysis, and citrate utilization. Therefore, based on data obtained from phenotypic and genotypic analysis, it is evident that strain ASS-1 T should be regarded as a novel species within the genus Pseudomonas, for which the name Pseudomonasfluvialis sp. nov. is proposed. The type strain is ASS-1 T (=KCTC 52437 T =CCM 8778 T ).

  10. In vitro and in vivo effects of Pseudomonas spp. and Bacillus sp. on Fusarium acuminatum, Botrytis cinerea and Aspergillus niger infecting cucumber

    Directory of Open Access Journals (Sweden)

    Jasmina Zdravković

    2015-09-01

    Full Text Available Cucumber (Cucumis sativus L is an important member of the Cucurbitaceae family. Production of healthy nursery is necessary for high-quality production of this crop in greenhouses and in fields. With the idea of minimizing the use of pesticides and mineral fertilizers to preserve soil quality, we investigated the effects of plant growth promoting bacteria (PGPB on growth promotion and protection of cucumber plants from phytopathogenic fungi. The effects of Pseudomonas spp. strains with different antifungal activities and Bacillus sp. Q10 strain with PGP activity were tested on cucumber plants. Antagonistic activity of Pseudomonas spp. against the growth of several phytopathogenic fungi isolated from cucumber: F. acuminatum, B. cinerea and A. niger, was observed. The influences of overnight cultures, supernatants and heat-stable antifungal factors were tested on the phytopathogenic fungi in vitro. Pseudomonas sp. K35 and K24 strains were more effective than P. chlororaphis Q16 and Pseudomonas sp. K27, showing 70-80% of fungal growth inhibition regardless of culture or fraction applied. The good antagonists that belong to pseudomonads and Bacillus sp. Q10 strain were used as mixtures for estimation of plant growth and health promoting effects on cucumber plants. Growth dynamics differed depending on the applied strain of Pseudomonas sp. The M3 treatment (a mixture of Bacillus sp. Q10 and P. chlororaphis Q16 stimulated the initial phase of growth, while M4 (a mixture of Bacillus sp. Q10 and Pseudomonas sp. K24 resulted in the maximal height at the final measurement. Significant differences in leaf and plant weight (M4, and leaf weight (M5, containing K35 strain were found after the treatments. No significant differences in chlorophyll and NBI level were observed in any of the tested combinations. The obtained results suggested that M3 was suitable for stimulation of the early phase of cucumber growth, while the mixtures M4 and M5 improved plant

  11. Effect of Garlic Oil on Attenuation of Pseudomonas aeruginosa Infection Induced in Mice

    International Nuclear Information System (INIS)

    Eltablawy, S.Y.; Elhifnawi, H.N.

    2010-01-01

    The antimicrobial activity and other medical benefits of garlic oil have been attributed to the presence of sulphides in it. Pseudomonas aeruginosa is a multidrug resistance opportunistic human pathogen that infect many patients .To control these infections, there is a need for other agents with greater antimicrobial activity and less toxicity. In this study, the effect of irradiated and non-irradiated garlic oil has been evaluated. The irradiation of garlic oil at 10.0 kGy decreased slightly its antibacterial activity against the tested Pseudomonas aeruginosa. The results revealed that there was no effect of garlic oil either irradiated or non-irradiated on the adherent cells formed by Pseudomonas aeruginosa tested organism on tissue culture plate. Garlic oil (irradiated or nonirradiated) was administrated subcutaneously as treatment for a mouse infection model. Bacteriological examination and mortality rate were used as indicators. The treatment with non-irradiated garlic oil decreased the number of bacteria in the infected group in contrast with the placebo group (saline), while, irradiation of garlic oil with 10.0 kGy had no effect on the infected bacteria. Also, the results indicated that, the treatment with non-irradiated garlic oil decreased the mortality in comparison with irradiated garlic oil which did not show any effect. Scanning electron microscopy study revealed that there were morphological changes in the Pseudomonas aeruginosa treated with non- irradiated garlic oil in comparison with untreated one

  12. 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 expressed sRNAs across strains and species. In this study, we have used RNA-seq to identify sRNAs in P.putidaDOT-T1E and Pseudomonas extremaustralis 14-3b. This is the first strain of P.extremaustralis and the second strain of P.putida to have their transcriptomes analysed for sRNAs, and we identify...... the presence of around 150 novel sRNAs in each strain. Furthermore, we provide a comparison based on sequence conservation of all the sRNAs detected by RNA-seq in the Pseudomonas species investigated so far. Our results show that the extent of sRNA conservation across different species is very limited...

  13. Ultraviolet-B lethal damage on Pseudomonas aeruginosa

    International Nuclear Information System (INIS)

    Degiorgi, C.F.; Fernandez, R.O.; Pizarro, R.A.

    1996-01-01

    Pseudomonas aeruginosa has shown an increased sensitivity compared with that of Escherichia coli and Enterobacter cloacae, when they were exposed to 0.4 kJ/m2 of ultraviolet-B radiation. The rapid decay in cell viability observed in Pseudomonas aeruginosa after the irradiation was influenced by factors such as culture media and the presence of pyocyanine during the irradiation. The radioinduced lethal damage could be prevented by photoreactivating treatment, indicating that pyrimidine dimer formation was the mechanism causing bacterial death. The results indicate that several environmental conditions may act as protective agents against ultraviolet-B-induced damage

  14. Antagonistic effect of Pseudomonas aeruginosa isolates from various ecological niches on Vibrio species pathogenic to crustaceans

    Institute of Scientific and Technical Information of China (English)

    Prabhakaran Priyaja; Puthumana Jayesh; Neil Scolastin Correya; Balachandran Sreelakshmi; Naduthalmuriparambil S Sudheer; Rosamma Philip; Isaac Sarogeni Bright Singh

    2014-01-01

    Objective: To abrogate pathogenic vibrios in aquaculture by testing the potential of Pseudomonas isolates from fresh water, brackish and marine environments as probiotics.Methods:Antagonistic activity of the compound against 7 Vibrio spp. was performed. Influence of salinity on the production of pyocyanin and the toxicity was done through the compound using brine shrimp lethality assay. Molecular characterization was performed to confirm that the isolates werePseudomonas aeruginosa. Results: Salinity was found to regulate the levels of pyocyanin production, with 5-10 g/L as the optimum. All Pseudomonas isolates grew at salinities ranging from 5 to 70 g/L. Isolates of marine origin produced detectable levels of pyocyanin up to 45 g/L salinity. Brackish and freshwater isolates ceased to produce pyocyanin at salinities above 30 g/L and 20 g/L, respectively. Culture supernatants of all 5 Pseudomonas isolates possessed the ability to restrict the growth of Vibrio spp. and maximum antagonistic effect on Vibrio harveyi was obtained when they were grown at salinities of 5 to 10 g/L. The marine isolate MCCB117, even when grown at a salinity of 45 g/L possessed the ability to inhibit Vibrio spp.Conclusions:Purification and structural elucidation of antagonistic compound were carried out. ideal for application in freshwater, MCCB102 and MCCB103 in brackish water and MCCB117 and The present investigation showed that Pseudomonas aeruginosa MCCB119 would be MCCB118 in marine aquaculture systems as putative probiotics in the management of vibrios.

  15. Optimal decolorization and kinetic modeling of synthetic dyes by Pseudomonas strains.

    Science.gov (United States)

    Yu, J; Wang, X; Yue, P L

    2001-10-01

    Pseudomonas spp were isolated from an anaerobic-aerobic dyeing house wastewater treatment facility as the most active azo-dye degraders. Decolorization of azo dyes and non-azo dyes including anthraquinone, metal complex and indigo was compared with individual strains and a bacterial consortium consisting of the individual strain and municipal sludge (50 50wt). The consortium showed a significant improvement on decolorization of two recalcitrant non-azo dyes, but little effect on the dyes that the individual strains could degrade to a great or moderate extent. Decolorization of Acid violet 7 (monoazo) by a Pseudomonas strain GM3 was studied in detail under various conditions. The optimum decolorization activity was observed in a narrow pH range (7-8), a narrow temperature range (35-40 degrees C), and at the presence of organic and ammonium nitrogen. Nitrate had a severe inhibitory effect on azo dye decolorization: 10 mg/L led to 50% drop in decolorization activity and 1000 mg/L to complete activity depression. A kinetic model is established giving the dependence of decolorization rate on cell mass concentration (first-order) and dye concentration (half order). The rate increased with temperature from 10 to 35 C, which can be predicted by Arrhenius equation with the activation energy of 16.87 kcal/mol and the frequency factor of 1.49 x 10(11) (mg L)1/2/g DCM min.

  16. Pseudomonas aeruginosa endophthalmitis masquerading as chronic uveitis

    Directory of Open Access Journals (Sweden)

    Kalpana Badami Nagaraj

    2013-01-01

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

  17. T helper cell subsets specific for Pseudomonas aeruginosa in healthy individuals and patients with cystic fibrosis.

    Directory of Open Access Journals (Sweden)

    Hannah K Bayes

    Full Text Available We set out to determine the magnitude of antigen-specific memory T helper cell responses to Pseudomonas aeruginosa in healthy humans and patients with cystic fibrosis.Peripheral blood human memory CD4(+ T cells were co-cultured with dendritic cells that had been infected with different strains of Pseudomonas aeruginosa. The T helper response was determined by measuring proliferation, immunoassay of cytokine output, and immunostaining of intracellular cytokines.Healthy individuals and patients with cystic fibrosis had robust antigen-specific memory CD4(+ T cell responses to Pseudomonas aeruginosa that not only contained a Th1 and Th17 component but also Th22 cells. In contrast to previous descriptions of human Th22 cells, these Pseudomonal-specific Th22 cells lacked the skin homing markers CCR4 or CCR10, although were CCR6(+. Healthy individuals and patients with cystic fibrosis had similar levels of Th22 cells, but the patient group had significantly fewer Th17 cells in peripheral blood.Th22 cells specific to Pseudomonas aeruginosa are induced in both healthy individuals and patients with cystic fibrosis. Along with Th17 cells, they may play an important role in the pulmonary response to this microbe in patients with cystic fibrosis and other conditions.

  18. BOX-PCR is an adequate tool for typing of clinical Pseudomonas aeruginosa isolates

    Directory of Open Access Journals (Sweden)

    Katarzyna Rymuza

    2012-01-01

    Full Text Available In this study, the BOX-PCR fingerprinting technique was evaluated for the discrimination of clinical Pseudomonas aeruginosa isolates. All isolates were typeable and nearly half showed unique banding patterns. According to our results, BOX-PCR fingerprinting is applicable for typing of Pseudomonas aeruginosa isolates and can be considered a useful complementary tool for epidemiological studies of members of this genus. (Folia Histochemica et Cytobiologica 2011; Vol. 49, No. 4, pp. 734–738

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

    Directory of Open Access Journals (Sweden)

    Shabana Bharathi

    2014-01-01

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

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

    DEFF Research Database (Denmark)

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

    2010-01-01

    We review the recent advances in the understanding of the Pseudomonas aeruginosa biofilm lifestyle from studies using in vitro laboratory setups such as flow chambers and microtiter trays. Recent work sheds light on the role of nutrients, motility, and quorum sensing in structure formation in P....... aeruginosa biofilms. The second messenger, c-di-GMP, is established as an important regulator of the synthesis of polysaccharide and protein components of the biofilm matrix. Extracellular DNA is shown to be an essential component of the biofilm matrix. It has become apparent that biofilm formation involves...... interactions between different subpopulations. The molecular mechanisms underlying the tolerance of biofilm bacteria to antimicrobial agents are beginning to be unraveled, and new knowledge has been obtained regarding the environmental cues and regulatory mechanisms involved in biofilm dispersal....

  1. Predictors of Pseudomonas and methicillin-resistant Staphylococcus aureus in hospitalized patients with healthcare-associated pneumonia.

    Science.gov (United States)

    Metersky, Mark L; Frei, Christopher R; Mortensen, Eric M

    2016-01-01

    Patients with healthcare-associated pneumonia (HCAP) are at high risk of infection with multidrug-resistant (MDR) pathogens. Factors discriminating infection with MDR Gram-negative (MDR-GN) organism from infection with methicillin-resistant Staphylococcus aureus (MRSA) are not well understood and patients are often treated for both organisms. This study was performed to determine risk factors predicting pneumonia due to Pseudomonas versus MRSA. Veterans age ≥65 hospitalized with HCAP between 2002 and 2012 were identified from the Veterans Affairs administrative databases. Patients were identified with Pseudomonas pneumonia, MRSA pneumonia or neither according to the International Classification of Diseases, 9th Revision, Clinical Modification codes. We assessed unadjusted and adjusted associations of patient characteristics and HCAP due to Pseudomonas or MRSA. Of the 61,651 patients with HCAP, 1156 (1.9%) were diagnosed with Pseudomonas pneumonia, 641 (1.0%) with MRSA pneumonia and 59,854 (97.1%) with neither. MRSA pneumonia was positively associated with male gender, age >74, diabetes, chronic obstructive pulmonary disease (COPD), recent nursing home or hospital stay, recent exposure to fluoroquinolone or antibiotics treating Gram-positive organisms, and severe pneumonia. MRSA pneumonia was negatively associated with complicated diabetes. Pseudomonas pneumonia was positively associated with recent hospital stay, immunocompromise, COPD, hemiplegia, recent exposure to inhaled corticosteroids, β-lactam/cephalosporin/carbapenem antibiotics, antibiotics against Gram-positive organisms, 'other antibiotics' and severe pneumonia. Pseudomonas pneumonia was negatively associated with age >84, higher socioeconomic status, drug abuse and diabetes. Patient characteristics may assist in identifying patients at risk for HCAP due to Pseudomonas or MRSA. © 2015 Asian Pacific Society of Respirology.

  2. 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.

  3. The emulsifying effect of biosurfactants produced by food spoilage organisms in Nigeria

    Directory of Open Access Journals (Sweden)

    Christianah O. Ogunmola

    2016-04-01

    Full Text Available Food spoilage organisms were isolated using standard procedures on Nutrient Agar, Cetrimide Agar and Pseudomonas Agar Base (supplemented with CFC. The samples were categorized as animal products (raw fish, egg, raw chicken, corned beef, pasteurized milk and plant products (vegetable salad, water leaf (Talinium triangulare, boiled rice, tomatoes and pumpkin leaf (Teifairia occidentalis.They were characterised as Pseudomonas putida, Pseudomonas aeruginosa, Pseudomonas stutzeri, Burkholderia pseudomallei, Serratia rubidaea, Corynebacterium pilosum, Bacillus subtilis, Bacillus mycoides, Bacillus laterosporus, Bacillus laterosporus, Serratia marcescens, Bacillus cereus, Bacillus macerans, Alcaligenes faecalis and Alcaligenes eutrophus. Preliminary screening for biosurfactant production was done using red blood haemolysis test and confirmed by slide test, drop collapse and oil spreading assay. The biosurfactant produced was purified using acetone and the composition determined initially using Molisch’s test, thin layer chromatography and gas chromatography mass spectrometry. The components were found to be ethanol, amino acids, butoxyacetic acid, hexadecanoic acid, oleic acid, lauryl peroxide, octadecanoic acid and phthalic acid. The producing organisms grew readily on several hydrocarbons such as crude oil, diesel oil and aviation fuel when used as sole carbon sources.  The purified biosurfactants produced were able to cause emulsification of kerosene (19.71-27.14% as well as vegetable oil (16.91-28.12% based on the emulsification index. This result suggests that the isolates can be an asset and further work can exploit their optimal potential in industries.

  4. Spoilage potential of Pseudomonas species isolated from goat milk.

    Science.gov (United States)

    Scatamburlo, T M; Yamazi, A K; Cavicchioli, V Q; Pieri, F A; Nero, L A

    2015-02-01

    Pseudomonas spp. are usually associated with spoilage microflora of dairy products due to their proteolytic potential. This is of particular concern for protein-based products, such as goat milk cheeses and fermented milks. Therefore, the goal of the present study was to characterize the proteolytic activity of Pseudomonas spp. isolated from goat milk. Goat milk samples (n=61) were obtained directly from bulk tanks on dairy goat farms (n=12), and subjected to a modified International Organization for Standardization (ISO) protocol to determine the number and proteolytic activity of Pseudomonas spp. Isolates (n=82) were obtained, identified by PCR, and subjected to pulsed-field gel electrophoresis with XbaI macro-restriction. Then, the isolates were subjected to PCR to detect the alkaline protease gene (apr), and phenotypic tests were performed to check proteolytic activity at 7°C, 25°C, and 35°C. Mean Pseudomonas spp. counts ranged from 2.9 to 4.8 log cfu/mL, and proteolytic Pseudomonas spp. counts ranged from 1.9 to 4.6 log cfu/mL. All isolates were confirmed to be Pseudomonas spp., and 41 were identified as Pseudomonas fluorescens, which clustered into 5 groups sharing approximately 82% similarity. Thirty-six isolates (46.9%) were positive for the apr gene; and 57 (69.5%) isolates presented proteolytic activity at 7°C, 82 (100%) at 25°C, and 64 (78%) at 35°C. The isolates were distributed ubiquitously in the goat farms, and no relationship among isolates was observed when the goat farms, presence of apr, pulsotypes, and proteolytic activity were taken into account. We demonstrated proteolytic activity of Pseudomonas spp. present in goat milk by phenotypic and genotypic tests and indicated their spoilage potential at distinct temperatures. Based on these findings and the ubiquity of Pseudomonas spp. in goat farm environments, proper monitoring and control of Pseudomonas spp. during production are critical. Copyright © 2015 American Dairy Science Association

  5. Interaction of bacteria-feeding soil flagellates and Pseudomonas spp

    DEFF Research Database (Denmark)

    Pedersen, Annette; Ekelund, Flemming; Johansen, Anders

    2010-01-01

    Pseudomonas strains may be used as alternatives to fungicides as some of them produce secondary metabolites, which can inhibit growth of plant pathogenic fungi. Increased knowledge of non-target effects of the antagonistic bacteria on other soil organisms as well as of the survival and predation...... resistance of the antagonistic bacteria is necessary for risk assessment and increased performance of antagonistic bacteria as biological control agents. In the present study, we aimed to investigate the difference between Pseudomonas spp. with respect to their predation resistance to and effects...... on the three different and common soil flagellates Bodo caudatus, Cercomonas longicauda, and Neocercomonas jutlandica. Two antagonistic Pseudomonas: Pseudomonas fluorescens CHA0 and P. fluorescens DR54 and two positive control strains: P. fluorescens DSM 50090T and Pseudomonas chlororaphis ATCC 43928 were...

  6. Expression analysis of the gacS mutant of Pseudomonas fluorescens SBW25

    NARCIS (Netherlands)

    Cheng, Xu; Bruijn, de Irene; Voort, van der M.; Raaijmakers, Jos

    2013-01-01

    Pseudomonas species are ubiquitous in plant-associated environments and produce an array of volatiles, enzymes and antimicrobials. The biosynthesis of many metabolites is regulated by the GacS/GacA two-component regulatory system. Transcriptome analysis of Pseudomonas fluorescens SBW25 revealed that

  7. 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.

  8. Allosteric control of internal electron transfer in cytochrome cd1 nitrite reductase

    DEFF Research Database (Denmark)

    Farver, Ole; Kroneck, Peter M H; Zumft, Walter G

    2003-01-01

    Cytochrome cd1 nitrite reductase is a bifunctional multiheme enzyme catalyzing the one-electron reduction of nitrite to nitric oxide and the four-electron reduction of dioxygen to water. Kinetics and thermodynamics of the internal electron transfer process in the Pseudomonas stutzeri enzyme have...... been studied and found to be dominated by pronounced interactions between the c and the d1 hemes. The interactions are expressed both in dramatic changes in the internal electron-transfer rates between these sites and in marked cooperativity in their electron affinity. The results constitute a prime...... example of intraprotein control of the electron-transfer rates by allosteric interactions....

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

    DEFF Research Database (Denmark)

    Johansen, Helle Krogh; Gøtzsche, Peter C

    2013-01-01

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

  10. Screening of Gibberellic Acid Production by Pseudomonas SPP

    International Nuclear Information System (INIS)

    Khine Zar Wynn Myint; Khin Mya Lwin; Myo Myint

    2010-12-01

    The microbial gibberellic acid (GA3) production of Pseudomonas spp., was studied and qualitatively indentified by UV spectrophotometer. 20 strains of Pseudomonas spp., were isolated and screened the gibberellic acid productivily in King's B medium. Among them, only four strains can produce microbial gibberellic acid. The Rf values and colour appearance under UV were the same as authentic gibberellic acid. Moreover, the gibberellic acid producer strains were identified as Pseudomonas spp., by cultural, biochemical and drug sensitivity pattern.

  11. Advances of naphthalene degradation in Pseudomonas putida ND6

    Science.gov (United States)

    Song, Fu; Shi, Yifei; Jia, Shiru; Tan, Zhilei; Zhao, Huabing

    2018-03-01

    Naphthalene is one of the most common and simple polycyclic aromatic hydrocarbons. Degradation of naphthalene has been greatly concerned due to its economic, free-pollution and its fine effect in Pseudomonas putida ND6. This review summarizes the development history of naphthalene degradation, the research progress of naphthalene degrading gene and naphthalene degradation pathway of Pseudomonas putida ND6, and the researching path of this strain. Although the study of naphthalene degradation is not consummate in Pseudomonas putida ND6, there is a potential capability for Pseudomonas putida ND6 to degrade the naphthalene in the further research.

  12. Antagonistic effect of Pseudomonas aeruginosa isolates from various ecological niches on Vibrio species pathogenic to crustaceans

    Directory of Open Access Journals (Sweden)

    Prabhakaran Priyaja

    2014-01-01

    Full Text Available Objective: To abrogate pathogenic vibrios in aquaculture by testing the potential of Pseudomonas isolates from fresh water, brackish and marine environments as probiotics. Methods: Purification and structural elucidation of antagonistic compound were carried out. Antagonistic activity of the compound against 7 Vibrio spp. was performed. Influence of salinity on the production of pyocyanin and the toxicity was done through the compound using brine shrimp lethality assay. Molecular characterization was performed to confirm that the isolates were Pseudomonas aeruginosa. Results: Salinity was found to regulate the levels of pyocyanin production, with 5-10 g/L as the optimum. All Pseudomonas isolates grew at salinities ranging from 5 to 70 g/L. Isolates of marine origin produced detectable levels of pyocyanin up to 45 g/L salinity. Brackish and freshwater isolates ceased to produce pyocyanin at salinities above 30 g/L and 20 g/L, respectively. Culture supernatants of all 5 Pseudomonas isolates possessed the ability to restrict the growth of Vibrio spp. and maximum antagonistic effect on Vibrio harveyi was obtained when they were grown at salinities of 5 to 10 g/L. The marine isolate MCCB117, even when grown at a salinity of 45 g/L possessed the ability to inhibit Vibrio spp. Conclusions: The present investigation showed that Pseudomonas aeruginosa MCCB119 would be ideal for application in freshwater, MCCB102 and MCCB103 in brackish water and MCCB117 and MCCB118 in marine aquaculture systems as putative probiotics in the management of vibrios.

  13. Development of a real-time TaqMan assay to detect mendocina sublineage Pseudomonas species in contaminated metalworking fluids.

    Science.gov (United States)

    Saha, Ratul; Donofrio, Robert S; Bagley, Susan T

    2010-08-01

    A TaqMan quantitative real-time polymerase chain reaction (qPCR) assay was developed for the detection and enumeration of three Pseudomonas species belonging to the mendocina sublineage (P. oleovorans, P. pseudoalcaligenes, and P. oleovorans subsp. lubricantis) found in contaminated metalworking fluids (MWFs). These microbes are the primary colonizers and serve as indicator organisms of biodegradation of used MWFs. Molecular techniques such as qPCR are preferred for the detection of these microbes since they grow poorly on typical growth media such as R2A agar and Pseudomonas isolation agar (PIA). Traditional culturing techniques not only underestimate the actual distribution of these bacteria but are also time-consuming. The primer-probe pair developed from gyrase B (gyrB) sequences of the targeted bacteria was highly sensitive and specific for the three species. qPCR was performed with both whole cell and genomic DNA to confirm the specificity and sensitivity of the assay. The sensitivity of the assay was 10(1) colony forming units (CFU)/ml for whole cell and 13.7 fg with genomic DNA. The primer-probe pair was successful in determining concentrations from used MWF samples, indicating levels between 2.9 x 10(3) and 3.9 x 10(6) CFU/ml. In contrast, the total count of Pseudomonas sp. recovered on PIA was in the range of <1.0 x 10(1) to 1.4 x 10(5) CFU/ml for the same samples. Based on these results from the qPCR assay, the designed TaqMan primer-probe pair can be efficiently used for rapid (within 2 h) determination of the distribution of these species of Pseudomonas in contaminated MWFs.

  14. Silver against Pseudomonas aeruginosa biofilms

    DEFF Research Database (Denmark)

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

    2007-01-01

    bacteria in both the planktonic and biofilm modes of growth. The action of silver on mature in vitro biofilms of Pseudomonas aeruginosa, a primary pathogen of chronic infected wounds, was investigated. The results show that silver is very effective against mature biofilms of P. aeruginosa......, but that the silver concentration is important. A concentration of 5-10 ig/mL silver sulfadiazine eradicated the biofilm whereas a lower concentration (1 ig/mL) had no effect. The bactericidal concentration of silver required to eradicate the bacterial biofilm was 10-100 times higher than that used to eradicate...... planktonic bacteria. These observations strongly indicate that the concentration of silver in currently available wound dressings is much too low for treatment of chronic biofilm wounds. It is suggested that clinicians and manufacturers of the said wound dressings consider whether they are treating wounds...

  15. Potent Antibacterial Antisense Peptide-Peptide Nucleic Acid Conjugates Against Pseudomonas aeruginosa

    DEFF Research Database (Denmark)

    Ghosal, Anubrata; Nielsen, Peter E

    2012-01-01

    Pseudomonas aeruginosa is an opportunistic pathogen causing severe infections in hospital settings, especially with immune compromised patients, and the increasing prevalence of multidrug resistant strains urges search for new drugs with novel mechanisms of action. In this study we introduce...... significantly reduced bacterial survival. These results open the possibility of development of antisense antibacterials for treatment of Pseudomonas infections....

  16. Pseudomonas A1 influences the formation of hydroxyapatite and degrades bioglass

    International Nuclear Information System (INIS)

    Papadopoulou, E.; Papadopoulou, L.; Paraskevopoulos, K.M.; Koidis, P.; Sivropoulou, A.

    2009-01-01

    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 Ca 3 (PO 4 ) 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.

  17. Evidence for a role of biosurfactants produced by Pseudomonas fluorescens in the spoilage of fresh aerobically stored chicken meat.

    Science.gov (United States)

    Mellor, Glen E; Bentley, Jessica A; Dykes, Gary A

    2011-08-01

    Fresh chicken meat is a fat-rich environment and we therefore hypothesised that production of biosurfactants to increase bioavailability of fats may represent one way in which spoilage bacteria might enhance the availability of nutrients. Numbers of Pseudomonas were determined on a total of 20 fresh and 20 spoiled chicken thighs with skin. A total of 400 randomly isolated Pseudomonas colonies from fresh (200) and spoiled (200) chicken were screened for the presence of biosurfactant production. Biosurfactant producing strains represented 5% and 72% of the Pseudomonas spp. isolates from fresh (mean count 2.3 log(10) cfu g(-1)) and spoiled (mean count 7.4 log(10) cfu g(-1)) chicken skin, respectively. Partially-purified biosurfactants derived from a subgroup of four Pseudomonasfluorescens strains obtained through the screening process were subsequently used to investigate the role that the addition of these compounds plays in the spoilage of aerobically stored chicken. Emulsification potential of the four selected biosurfactants was measured against a range of hydrocarbons and oils. All four biosurfactants displayed a greater ability to emulsify rendered chicken fat than hydrocarbons (paraffin liquid, toluene and hexane) and oils (canola, olive, sunflower and vegetable). Storage trials (4 °C) of chicken meat treated with the four selected biosurfactants revealed a significantly greater (P increase in total aerobic count (1.3-1.7 log(10) cfu g(-1)) occurred following one day of incubation. These results indicate that biosurfactants produced by Pseudomonas spp. may play an important role in the spoilage of aerobically stored chicken meat by making nutrients more freely available and providing strains producing them with a competitive advantage. Copyright © 2011 Elsevier Ltd. All rights reserved.

  18. Frequent conjugative transfer accelerates adaptation of a broad-host-range plasmid to an unfavorable Pseudomonas putida host.

    Science.gov (United States)

    Heuer, Holger; Fox, Randal E; Top, Eva M

    2007-03-01

    IncP-1 plasmids are known to be promiscuous, but it is not understood if they are equally well adapted to various species within their host range. Moreover, little is known about their fate in bacterial communities. We determined if the IncP-1beta plasmid pB10 was unstable in some Proteobacteria, and whether plasmid stability was enhanced after long-term carriage in a single host and when regularly switched between isogenic hosts. Plasmid pB10 was found to be very unstable in Pseudomonas putida H2, and conferred a high cost (c. 20% decrease in fitness relative to the plasmid-free host). H2(pB10) was then evolved under conditions that selected for plasmid maintenance, with or without regular plasmid transfer (host-switching). When tested in the ancestral host, the evolved plasmids were more stable and their cost was significantly reduced (9% and 16% for plasmids from host-switched and nonswitched lineages, respectively). Our findings suggest that IncP-1 plasmids can rapidly adapt to an unfavorable host by improving their overall stability, and that regular conjugative transfer accelerates this process.

  19. Pseudomonas floridensis sp. nov., a bacterial pathogen isolated from tomato.

    Science.gov (United States)

    Timilsina, Sujan; Minsavage, Gerald V; Preston, James; Newberry, Eric A; Paret, Matthews L; Goss, Erica M; Jones, Jeffrey B; Vallad, Gary E

    2018-01-01

    An unusual fluorescent pseudomonad was isolated from tomato exhibiting leaf spot symptoms similar to bacterial speck. Strains were fluorescent, oxidase- and arginine-dihydrolase-negative, elicited a hypersensitive reaction on tobacco and produced a soft rot on potato slices. However, the strains produced an unusual yellow, mucoid growth on media containing 5 % sucrose that is not typical of levan. Based on multilocus sequence analysis using 16S rRNA, gap1, gltA, gyrB and rpoD, these strains formed a distinct phylogenetic group in the genus Pseudomonas and were most closely related to Pseudomonas viridiflava within the Pseudomonassyringae complex. Whole-genome comparisons, using average nucleotide identity based on blast, of representative strain GEV388 T and publicly available genomes representing the genus Pseudomonas revealed phylogroup 7 P. viridiflava strain UASW0038 and P. viridiflava type strain ICMP 2848 T as the closest relatives with 86.59 and 86.56 % nucleotide identity, respectively. In silico DNA-DNA hybridization using the genome-to-genome distance calculation method estimated 31.1 % DNA relatedness between GEV388 T and P. viridiflava ATCC 13223 T , strongly suggesting the strains are representatives of different species. These results together with Biolog GEN III tests, fatty acid methyl ester profiles and phylogenetic analysis using 16S rRNA and multiple housekeeping gene sequences demonstrated that this group represents a novel species member of the genus Pseudomonas. The name Pseudomonas floridensis sp. nov. is proposed with GEV388 T (=LMG 30013 T =ATCC TSD-90 T ) as the type strain.

  20. Mutant Prevention Concentrations of Imipenem and Meropenem against Pseudomonas aeruginosa and Acinetobacter baumannii

    Directory of Open Access Journals (Sweden)

    E. Dahdouh

    2014-01-01

    Full Text Available The aim of this study was to determine the usefulness of the MPC of carbapenems against clinical isolates of Pseudomonas spp. and Acinetobacter spp. and to assess its possible relationship with mechanisms of resistance. Detection of the mechanisms of resistance was performed using Antibiotic Susceptibility Testing, Double Disk Synergy, disk antagonism, addition of NaCl to the medium, addition of PBA or EDTA to Carbapenem disks, addition of PBA to Cefoxitin disks, and CCCP test for 10 Pseudomonas spp. and Acinetobacter baumannii strains. The MIC and MPC were determined using the broth macrodilution and plate dilution methods, respectively. Four Acinetobacter baumannii strains produced MBL. Two of them produced Oxacillinase and one produced ESBL. Two Pseudomonas spp. isolates produced both KPC and MBL. The resistant Acinetobacter spp. and Pseudomonas spp. strains had higher MPC values than susceptible ones. However, the Mutant Selection Window was found to be dependent on the degree of resistance but not on a particular mechanism of resistance. The usefulness of the MPC was found to be dependent on its value. Based on our data, we recommend determining the MPC for each isolate before using it during treatment. Furthermore, the use of T>MSW instead of T>MIC is suggested.

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

    DEFF Research Database (Denmark)

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

    2008-01-01

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

  2. Structural characterization of pyoverdines produced by Pseudomonas putida KT2440 and Pseudomonas taiwanensis VLB120.

    Science.gov (United States)

    Baune, Matthias; Qi, Yulin; Scholz, Karen; Volmer, Dietrich A; Hayen, Heiko

    2017-08-01

    The previously unknown sequences of several pyoverdines (PVD) produced by a biotechnologically-relevant bacterium, namely, Pseudomonas taiwanensis VLB120, were characterized by high performance liquid chromatography (HPLC)-high resolution mass spectrometry (HRMS). The same structural characterization scheme was checked before by analysis of Pseudomonas sp. putida KT2440 samples with known PVDs. A new sample preparation strategy based on solid-phase extraction was developed, requiring significantly reduced sample material as compared to existing methods. Chromatographic separation was performed using hydrophilic interaction liquid chromatography with gradient elution. Interestingly, no signals for apoPVDs were detected in these analyses, only the corresponding aluminum(III) and iron(III) complexes were seen. The chromatographic separation readily enabled separation of PVD complexes according to their individual structures. HPLC-HRMS and complementary fragmentation data from collision-induced dissociation and electron capture dissociation enabled the structural characterization of the investigated pyoverdines. In Pseudomonas sp. putida KT2240 samples, the known pyoverdines G4R and G4R A were readily confirmed. No PVDs have been previously described for Pseudomonas sp. taiwanensis VLB120. In our study, we identified three new PVDs, which only differed in their acyl side chains (succinic acid, succinic amide and malic acid). Peptide sequencing by MS/MS provided the sequence Orn-Asp-OHAsn-Thr-AcOHOrn-Ser-cOHOrn. Of particular interest is the presence of OHAsn, which has not been reported as PVD constituent before.

  3. Chemical sanitizers to control biofilms formed by two Pseudomonas species on stainless steel surface Sanificantes químicos no controle de biofilmes formados por duas espécies de Pseudomonas em superfície de aço inoxidável

    Directory of Open Access Journals (Sweden)

    Danila Soares Caixeta

    2012-03-01

    Full Text Available The biofilm formation of Pseudomonas aeruginosa and Pseudomonas fluorescens on AISI 304 stainless steel in the presence of reconstituted skim milk under different temperatures was conducted, and the potential of three chemical sanitizers in removing the mono-species biofilms formed was compared. Pseudomonas aeruginosa cultivated in skim milk at 28 °C presented better growth rate (10.4 log CFU.mL-1 when compared with 3.7 and 4.2 log CFU.mL-1 for P. aeruginosa and P. fluorescens cultivated at 7 °C, respectively. Pseudomonas aeruginosa formed biofilm when cultivated at 28 °C. However, only the adhesion of P. aeruginosa and P. fluorescens was observed when incubated at 7 °C. The sodium dichloroisocyanurate was the most efficient sanitizer in the reduction of the adhered P. aeruginosa cells at 7 and 28 °C and those on the biofilm, respectively. The hydrogen peroxide was more effective in the reduction of adhered cells of P. fluorescens at 7 °C.A capacidade de adesão e formação de biofilme por Pseudomonas aeruginosa e Pseudomonas fluorescens em aço inoxidável AISI 304, na presença de leite desnatado resconstituído sobre diferentes temperaturas foi conduzido e o potencial de três sanificantes químicos na remoção de biofilmes monoespécies foi comparado. Pseudomonas aeruginosa cultivada em leite desnatado a 28 °C apresentou melhor crescimento (10,4 log UFC.mL-1 quando comparado com 3,7 and 4,2 log UFC.mL-1 para P. aeruginosa e P. fluorescens cultivadas a 7 °C, respectivamente. Pseudomonas aeruginosa formou biofilme quando cultivada a 28 °C. Contudo foi observado somente adesão de P. aeruginosa e P. fluorescens quando incubada a 7 °C. O dicloroisocianurato de sódio foi o sanificante mais eficiente na redução de células aderidas e em biofilme de P. aeruginosa a 7 e 28 °C, respectivamente. O peróxido de hidrogênio foi o mais eficiente na redução de células aderidas de P. fluorescens a 7 °C.

  4. Trehalose 6-phosphate phosphatases of Pseudomonas aeruginosa.

    Science.gov (United States)

    Cross, Megan; Biberacher, Sonja; Park, Suk-Youl; Rajan, Siji; Korhonen, Pasi; Gasser, Robin B; Kim, Jeong-Sun; Coster, Mark J; Hofmann, Andreas

    2018-04-24

    The opportunistic bacterium Pseudomonas aeruginosa has been recognized as an important pathogen of clinical relevance and is a leading cause of hospital-acquired infections. The presence of a glycolytic enzyme in Pseudomonas, which is known to be inhibited by trehalose 6-phosphate (T6P) in other organisms, suggests that these bacteria may be vulnerable to the detrimental effects of intracellular T6P accumulation. In the present study, we explored the structural and functional properties of trehalose 6-phosphate phosphatase (TPP) in P. aeruginosa in support of future target-based drug discovery. A survey of genomes revealed the existence of 2 TPP genes with either chromosomal or extrachromosomal location. Both TPPs were produced as recombinant proteins, and characterization of their enzymatic properties confirmed specific, magnesium-dependent catalytic hydrolysis of T6P. The 3-dimensional crystal structure of the chromosomal TPP revealed a protein dimer arising through β-sheet expansion of the individual monomers, which possess the overall fold of halo-acid dehydrogenases.-Cross, M., Biberacher, S., Park, S.-Y., Rajan, S., Korhonen, P., Gasser, R. B., Kim, J.-S., Coster, M. J., Hofmann, A. Trehalose 6-phosphate phosphatases of Pseudomonas aeruginosa.

  5. Bacterial community structure and diversity in the gut of Muga silkworm, Antheraea assamensis (Lepidoptera: Saturniidae) from India.

    Science.gov (United States)

    Gandotra, Sakshi; Kumar, Archna; Naga, Kailash; Bhuyan, Pinky Moni; Gogoi, Dip K; Sharma, Kirti; Subramanian, Sabtharishi

    2018-04-17

    Muga silkworm, Antheraea assamensis is exclusively present in the North Eastern regions of India and rearing of this silkworm is a vocation unique to this region in the world. Through culture dependent techniques, generic identification using 16s rRNA probes, diversity analysis and qualitative screening for enzyme activities, our studies have identified a number of bacterial isolates viz., Bacillus spp, Serratia marcescens, Stenotrophomonas maltophilia, Pseudomonas stutzeri, Acinetobacter sp. and Alcaligens sp. inhabiting the gut of muga silkworm. Analysis of culturable bacterial community from the gut of A. assamensis revealed that Bacillus (54%) was the predominant bacterial genera followed by Serratia (24%), Pseudomonas (10%) and Alcaligens (6%). Significant differences in Shannon and the Simpson diversity indices of gut bacteria were recorded for A. assamensis collected from different regions. Shannon (H) and Simpson (D) diversity indices were found to be the highest for A. assamensis from Titabar region (H= 4.73 ± 0.43), (D= 10.00 ± 0.11) and the lowest for Mendipathar region (H= 2.1 ± 0.05), (D= 0.04 ± 0.00) respectively of North Eastern India. Qualitative screening for enzymatic activities identified a number of gut bacterial isolates having significantly higher cellulose, amylase, lipase activities which may probably be contributing to the digestion and nutrition of their host insect, A. assamensis. This article is protected by copyright. All rights reserved. © 2018 The Royal Entomological Society.

  6. Soil burial method for plastic degradation performed by Pseudomonas PL-01, Bacillus PL-01, and indigenous bacteria

    Science.gov (United States)

    Shovitri, Maya; Nafi'ah, Risyatun; Antika, Titi Rindi; Alami, Nur Hidayatul; Kuswytasari, N. D.; Zulaikha, Enny

    2017-06-01

    Lately, plastic bag is becoming the most important pollutant for environment since it is difficult to be naturally degraded due to it consists of long hydrocarbon polymer chains. Our previous study indicated that our pure isolate Pseudomonas PL-01 and Bacillus PL-01 could degrade about 10% plastic bag. This present study was aimed to find out whether Pseudomonas PL01 and Bacillus PL01 put a positive effect to indigenous bacteria from marginal area in doing plastic degradation with a soil burial method. Beach sand was used as a representative marginal area, and mangrove sediment was used as a comparison. Plastics were submerged into unsterile beach sand with 10% of Pseudomonas PL-01 or Bacillus PL-01 containing liquid minimal salt medium (MSM) separately, while other plastics were submerged into unsterile mangrove sediments. After 4, 8, 12 and 16 weeks, their biofilm formation on their plastic surfaces and plastic degradation were measured. Results indicated that those 2 isolates put positive influent on biofilm formation and plastic degradation for indigenous beach sand bacteria. Bacillus PL-01 put higher influent than Pseudomonas PL-01. Plastic transparent was preferable degraded than black and white plastic bag `kresek'. But anyhow, indigenous mangrove soil bacteria showed the best performance in biofilm formation and plastic degradation, even without Pseudomonas PL-01 or Bacillus PL-01 addition. Fourier Transform Infrared (FTIR) analysis complemented the results; there were attenuated peaks with decreasing peaks transmittances. This FTIR peaks indicated chemical functional group changes happened among the plastic compounds after 16 weeks incubation time.

  7. Interactions between biosurfactant-producing Pseudomonas and Phytophthora species

    NARCIS (Netherlands)

    Tran, H.

    2007-01-01

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

  8. Draft Genome Sequence of an Invasive Multidrug-Resistant Strain, Pseudomonas aeruginosa BK1, Isolated from a Keratitis Patient

    KAUST Repository

    Jeganathan, Lakshmi Priya; Prakash, Logambiga; Neelamegam, Sivakumar; Antony, Aju; Alqarawi, Sami; Prajna, Lalitha; Devarajan, Bharanidharan; Mohankumar, Vidyarani

    2014-01-01

    Pseudomonas aeruginosa infections are difficult to treat due to the presence of a multitude of virulence factors and antibiotic resistance. Here, we report the draft genome sequence of P. aeruginosa BK1, an invasive and multidrug-resistant strain

  9. Transformation of carbon tetrachloride by Pseudomonas sp. strain KC under denitrification conditions

    International Nuclear Information System (INIS)

    Criddle, C.S.; DeWitt, J.T.; Grbic-Galic, D.; McCarty, P.L.

    1990-01-01

    A denitrifying Pseudomonas sp. (strain KC) capable of transforming carbon tetrachloride (CT) was isolated from groundwater aquifer solids. Major products of the transformation of 14 C-labeled CT by Pseudomonas strain KC under denitrification conditions were 14 CO 2 and an unidentified water-soluble fraction. Little or no chloroform was produced. Addition of dissolved trace metals, notably, ferrous iron and cobalt, to the growth medium appeared to enhance growth of Pseudomonas strain KC while inhibiting transformation of CT. It is hypothesized that transformation of CT by this organism is associated with the mechanism of trace-metal scavenging

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

    Science.gov (United States)

    Johansen, Helle Krogh; Gøtzsche, Peter C

    2015-08-23

    Chronic pulmonary infection in cystic fibrosis results in progressive lung damage. Once colonisation of the lungs with Pseudomonas aeruginosa occurs, it is almost impossible to eradicate. Vaccines, aimed at reducing infection with Pseudomonas aeruginosa, have been developed. This is an update of a previously published review. To assess the effectiveness of vaccination against Pseudomonas aeruginosa in cystic fibrosis. We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Trials Register using the terms vaccines AND pseudomonas (last search 30 March 2015). We previously searched PubMed using the terms vaccin* AND cystic fibrosis (last search 30 May 2013). Randomised trials (published or unpublished) comparing Pseudomonas aeruginosa vaccines (oral, parenteral or intranasal) with control vaccines or no intervention in cystic fibrosis. The authors independently selected trials, assessed them and extracted data. Six trials were identified. Two trials were excluded since they were not randomised and one old, small trial because it was not possible to assess whether is was randomised. The three included trials comprised 483, 476 and 37 patients, respectively. No data have been published from one of the large trials, but the company stated in a press release that the trial failed to confirm the results from an earlier study and that further clinical development was suspended. In the other large trial, relative risk for chronic infection was 0.91 (95% confidence interval 0.55 to 1.49), and in the small trial, the risk was also close to one. In the large trial, one patient was reported to have died in the observation period. In that trial, 227 adverse events (4 severe) were registered in the vaccine group and 91 (1 severe) in the control group. In this large trial of a vaccine developed against flagella antigens, antibody titres against the epitopes contained in the vaccine were higher in the vaccine group compared to the placebo group (P Vaccines against

  11. Pseudomonas A1 influences the formation of hydroxyapatite and degrades bioglass

    Energy Technology Data Exchange (ETDEWEB)

    Papadopoulou, E. [Laboratory of General Microbiology, Section of Genetics, Development and Molecular Biology, School of Biology, Aristotle University of Thessaloniki, Thessaloniki 54124 (Greece); Papadopoulou, L. [School of Geology, Aristotle University of Thessaloniki, Thessaloniki 54124 (Greece); Paraskevopoulos, K.M. [Physics Department Solid State Physics Section, Aristotle University of Thessaloniki, Thessaloniki 54124 (Greece); Koidis, P. [Department of Fixed Prosthesis and Implant Prosthodontics, School of Dentistry, Aristotle University of Thessaloniki, Thessaloniki 54124 (Greece); Sivropoulou, A., E-mail: asivropo@bio.auth.g [Laboratory of General Microbiology, Section of Genetics, Development and Molecular Biology, School of Biology, Aristotle University of Thessaloniki, Thessaloniki 54124 (Greece)

    2009-12-15

    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 Ca{sub 3}(PO{sub 4}){sub 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.

  12. Verspreiding, diversiteit en activiteit van antibioticaproducerende Pseudomonas spp

    NARCIS (Netherlands)

    Souza, J.T.

    2003-01-01

    Pseudomonas bacteriën zijn potentiële antagonisten van diverse plantenpathogene schimmels en oömyceten. De productie van antibiotica speelt een belangrijke rol in de activiteit van diverse Pseudomonas isolaten tegen plantenpathogenen. Dit artikel is een samenvatting van het proefschrift getiteld

  13. 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...

  14. Enhancing biodegradation of wastewater by microbial consortia with fractional factorial design

    Energy Technology Data Exchange (ETDEWEB)

    Chen Yuancai [State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou, 510640, Guangdong (China); Lin Chejen, E-mail: Jerry.Lin@lamar.edu [Department of Civil Engineering, Lamar University, Beaumont, TX 77710-0024 (United States); School of Environmental Science and Engineering, South China University of Technology, Guangzhou, 510006, Guangdong (China); Jones, Gavin [Texas Research Institute for Environmental Studies, Sam Houston State University, Huntsville, TX 77341-2506 (United States); Fu Shiyu; Zhan Huaiyu [State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou, 510640, Guangdong (China)

    2009-11-15

    Batch experiments were conducted on the degradation of synthetic and municipal wastewater by six different strains, i.e., Agrobacterium sp., Bacillus sp., Enterobacter cloacae, Gordonia, Pseudomonas stutzeri, Pseudomonas putida. By applying a fractional factorial design (FFD) of experiments, the influence of each strain and their interactions were quantified. An empirical model predicting the treatment efficiency was built based on the results of the FFD experiments with an R{sup 2} value of 99.39%. For single strain, Enterobacter cloacae, Gordonia and P. putida (p = 0.008, 0.009 and 0.023, respectively) showed significant enhancement on organic removal in the synthetic wastewater. Positive interaction from Enterobacter cloacae, Gordonia (p = 0.046) was found, indicating that syntrophic interaction existed, and their coexistence can improve total organic carbon (TOC) degradation. Verification experiments were performed to evaluate the effect of bioaugmentation by introducing three selected strains into an activated sludge reactor for treating municipal wastewater. The removal efficiency of TOC with the bioaugmentation was increased from 67-72% to 80-84% at an influent TOC concentration of 200 mg/L. The results derived from this study indicate that the FFD is a useful screening tool for optimizing the microbial community to enhance treatment efficiency.

  15. Enhancing biodegradation of wastewater by microbial consortia with fractional factorial design

    International Nuclear Information System (INIS)

    Chen Yuancai; Lin Chejen; Jones, Gavin; Fu Shiyu; Zhan Huaiyu

    2009-01-01

    Batch experiments were conducted on the degradation of synthetic and municipal wastewater by six different strains, i.e., Agrobacterium sp., Bacillus sp., Enterobacter cloacae, Gordonia, Pseudomonas stutzeri, Pseudomonas putida. By applying a fractional factorial design (FFD) of experiments, the influence of each strain and their interactions were quantified. An empirical model predicting the treatment efficiency was built based on the results of the FFD experiments with an R 2 value of 99.39%. For single strain, Enterobacter cloacae, Gordonia and P. putida (p = 0.008, 0.009 and 0.023, respectively) showed significant enhancement on organic removal in the synthetic wastewater. Positive interaction from Enterobacter cloacae, Gordonia (p = 0.046) was found, indicating that syntrophic interaction existed, and their coexistence can improve total organic carbon (TOC) degradation. Verification experiments were performed to evaluate the effect of bioaugmentation by introducing three selected strains into an activated sludge reactor for treating municipal wastewater. The removal efficiency of TOC with the bioaugmentation was increased from 67-72% to 80-84% at an influent TOC concentration of 200 mg/L. The results derived from this study indicate that the FFD is a useful screening tool for optimizing the microbial community to enhance treatment efficiency.

  16. Aderência in vitro do Staphylococcus epidermidis e da Pseudomonas alcaligenes em lentes intra-oculares In vitro adherence of Staphylococcus epidermidis and Pseudomonas alcaligenes to intraocular lenses

    Directory of Open Access Journals (Sweden)

    Patrícia Ioschpe Gus

    2006-06-01

    Full Text Available OBJETIVO: Quantificar e comparar a aderência in vitro das bactérias Staphylococcus epidermidis e Pseudomonas alcaligenes em diferentes tipos de lentes intra-oculares (LIOs. MÉTODOS: Quatorze lentes intra-oculares foram usadas no experimento. Quatro de polimetilmetacrilato (PMMA, quatro de silicone, quatro de hidrogel e duas de acrílico. Oito lentes intra-oculares foram colocadas em oito tubos de ensaio contendo 4 ml de suspensão de Pseudomonas alcaligenes, e seis lentes intra-oculares foram colocadas em seis tubos de ensaio contendo 4 ml de suspensão de Staphylococcus epidermidis. A concentração do caldo utilizada para o teste de aderência foi de 10(8 unidades formadoras de colônias por mililitro (CFU/mL que corresponde a 0,5 na escala de McFarland. As lentes foram incubadas a 37° por duas horas. Após, foram removidas dos caldos e enxaguadas em água destilada estéril por duas vezes. As lentes foram cultivadas em placas de ágar-sangue a 35-37° e evaliadas a cada 24h por um período de 72h. Nas amostras que tiveram crescimento bacteriano, foram contadas as colônias utilizando os métodos convencionais de laboratório. Todos os ensaios foram executados em duplicata. RESULTADOS: A aderência do Staphylococcus epidermidis nas lentes de PMMA foi menor se comparada com as de silicone e de hidrogel. A aderência daPseudomonas alcaligenes nas lentes de hidrogel foi menor se comparada com as de silicone, PMMA e acrílico. CONCLUSÃO: Os resultados sugerem que a aderência do Staphylococcus epidermidis e da Pseudomonas alcaligenes nas lentes intra-oculares é influenciada pelo tipo de material da lente e pela espécie do microorganismo. A aderência bacteriana pode ter papel importante na patogenicidade da endoftalmite pós-cirurgia de catarata.PURPOSE: To quantify and compare the in vitro adherence of Staphylococcus epidermidis and Pseudomonas alcaligenes to different intraocular lenses (IOLs. METHODS: Fourteen intraocular lenses were

  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.

  18. Exacerbation of bronchiectasis by Pseudomonas monteilii: a case report.

    Science.gov (United States)

    Aditi; Shariff, Malini; Beri, Kiran

    2017-07-24

    Pseudomonas spp are important opportunistic and nosocomial pathogens. One such species is Pseudomonas monteilii (P. monteilii). It has been described as an environmental contaminant and potential pathogen. We identified this organism as the causative agent of an exacerbation of bronchiectasis and an environmental contaminant in our hospital on two separate occasions. P. monteilii was the cause of an exacerbation of bronchiectasis in a 30-year-old HIV negative male. Patient presented with cough with sputum production and exertional dyspnea. The isolate was recovered from a sputum sample in significant counts and definitively identified by Matrix-Assisted Laser Desorption/Ionisation- Time of Flight Mass Spectrometry (MALDI-TOF MS). He was treated with piperacillin-tazobactam and recovered clinically and microbiologically. Another two isolates of the organism were contaminants from the hospital environment. The three isolates were susceptible to all tested antibiotics. Typing by Random amplification of polymorphic DNA (RAPD) found no clonal relationship between them. Less common species of Pseudomonas need to be identified accurately. This organism is identified by commonly used phenotypic systems as P. putida which may have contributed to a lower reported prevalence. P. monteilii is a known environmental contaminant and must also be considered as a potential pathogen, particularly in patients with chronic lung disease.

  19. Uranium and thorium uptake by live and dead cells of Pseudomonas Sp

    International Nuclear Information System (INIS)

    Siva Prasath, C.S.; Manikandan, N.; Prakash, S.

    2010-01-01

    This study presents uptake of uranium (U) and thorium (Th) by live and dead cells of Pseudomonas Sp. Increasing concentration of U and Tb showed decrease in absorption by Pseudomonas Sp. Dead cells of Pseudomonas Sp. exhibited same or more uptake of U and Th than living cells. Increasing temperature promotes uptake of U and Th by Pseudomonas Sp. (author)

  20. Decreased outer membrane permeability in imipenem-resistant mutants of Pseudomonas aeruginosa.

    OpenAIRE

    Trias, J; Dufresne, J; Levesque, R C; Nikaido, H

    1989-01-01

    The outer membrane of imipenem-resistant mutants of Pseudomonas aeruginosa was shown to have decreased permeability to imipenem but not to cephaloridine. These experiments were performed with intact cells and liposomes containing imipenem-hydrolyzing beta-lactamase derived from Pseudomonas maltophilia, in both cases utilizing an imipenem concentration of 50 microM. In contrast, liposome swelling assays using imipenem at 8 mM detected no significant difference between the imipenem-resistant mu...

  1. Cloning of genes required for hypersensitivity and pathogenicity in Pseudomonas syringae pv. aptata.

    Science.gov (United States)

    Minardi, P

    1995-01-01

    A genomic library of Pseudomonas syringae pv. aptata strain NCPPB 2664, which causes bacterial blight of sugar beet, lettuce and other plants, was constructed in the cosmid vector pCPP31. The 13.4 kb EcoRI fragment of the cosmid pHIR11, containing the hrp (hypersensitive response and pathogenicity) gene cluster of the closely related bacterium Pseudomonas syringae pv. syringae strain 61, was used as a probe to identify a homologous hrp gene cluster in P. syringae pv. aptata. Thirty of 2500 cosmid clones, screened by colony hybridization, gave a strong hybridization signal with the probe, but none of these conferred to the non-pathogenic bacterium, Pseudomonas fluorescens, the ability to elicit the hypersensitive response (HR) in tobacco. Southern blot analysis of EcoRI-digested genomic DNA of P. syringae pv. aptata showed hybridizing bands of 12 kb and 4.4 kb. Only a 12 kb fragment hybridized in digests of the cosmids. Cosmid clone pCPP1069 was mutagenized with Tn10-minitet and marker-exchanged into the genome of P. syringae pv. aptata. Three resulting prototrophic mutant strains failed to elicit the HR in tobacco and to cause disease in lettuce. The DNA flanking the Tn10-minitet insertions from mutated derivatives of pCPP1069 hybridized with the 10.6 kb Bg/II fragment of pHIR11. These results indicate that P. syringae pv. aptata harbours hrp genes that are similar to, but arranged differently from, homologous hrp genes of P. syringae pv. syringae.

  2. Genotypische diversiteit en rhizosfeerkolonisatie van DAPG-producerende Pseudomonas spp.

    NARCIS (Netherlands)

    Bergsma-Vlami, M.

    2009-01-01

    Het antibioticum 2,4-diacetylphloroglucinol (DAPG) speelt een belangrijke rol in biologische bestrijding van verschillende plantenpathogenen door fluorescerende Pseudomonas-soorten. DAPG-producerende Pseudomonas-stammen zijn effectief in biologische bestrijding, maar hun saprofytisch vermogen is

  3. Functional bacterial amyloid increases Pseudomonas biofilm hydrophobicity and stiffness

    DEFF Research Database (Denmark)

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

    2015-01-01

    The success of Pseudomonas species as opportunistic pathogens derives in great part from their ability to form stable biofilms that offer protection against chemical and mechanical attack. The extracellular matrix of biofilms contains numerous biomolecules, and it has recently been discovered...... that in Pseudomonas one of the components includes β-sheet rich amyloid fibrils (functional amyloid) produced by the fap operon. However, the role of the functional amyloid within the biofilm has not yet been investigated in detail. Here we investigate how the fap-based amyloid produced by Pseudomonas affects biofilm...... hydrophobicity and mechanical properties. Using atomic force microscopy imaging and force spectroscopy, we show that the amyloid renders individual cells more resistant to drying and alters their interactions with hydrophobic probes. Importantly, amyloid makes Pseudomonas more hydrophobic and increases biofilm...

  4. The Pseudomonas community in metal-contaminated sediments as revealed by quantitative PCR: a link with metal bioavailability.

    Science.gov (United States)

    Roosa, Stéphanie; Wauven, Corinne Vander; Billon, Gabriel; Matthijs, Sandra; Wattiez, Ruddy; Gillan, David C

    2014-10-01

    Pseudomonas bacteria are ubiquitous Gram-negative and aerobic microorganisms that are known to harbor metal resistance mechanisms such as efflux pumps and intracellular redox enzymes. Specific Pseudomonas bacteria have been quantified in some metal-contaminated environments, but the entire Pseudomonas population has been poorly investigated under these conditions, and the link with metal bioavailability was not previously examined. In the present study, quantitative PCR and cell cultivation were used to monitor and characterize the Pseudomonas population at 4 different sediment sites contaminated with various levels of metals. At the same time, total metals and metal bioavailability (as estimated using an HCl 1 m extraction) were measured. It was found that the total level of Pseudomonas, as determined by qPCR using two different genes (oprI and the 16S rRNA gene), was positively and significantly correlated with total and HCl-extractable Cu, Co, Ni, Pb and Zn, with high correlation coefficients (>0.8). Metal-contaminated sediments featured isolates of the Pseudomonas putida, Pseudomonas fluorescens, Pseudomonas lutea and Pseudomonas aeruginosa groups, with other bacterial genera such as Mycobacterium, Klebsiella and Methylobacterium. It is concluded that Pseudomonas bacteria do proliferate in metal-contaminated sediments, but are still part of a complex community. Copyright © 2014 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

  5. Biodegradation of resorcinol byPseudomonas sp.

    Institute of Scientific and Technical Information of China (English)

    Nader Hajizadeh; Najibeh Shirzad; Ali Farzi; Mojtaba Salouti; Azra Momeni

    2016-01-01

    ABSTRACT Objective:To investigate the ability ofPseudomonas sp. isolated from East Azarbaijan, Iran in bioremediation of resorcinol. Methods: Resorcinol biodegradation was evaluated using spectrophotometry and confirmed by gas chromatography-mass spectroscopy. Results:This isolate was able to remove up to 37.12% of resorcinol from contaminated water. Reusability experiments had confirmed the biodegradation process which produced seven intermediate compounds. These intermediates were characterized by gas chromatography-mass spectroscopy technique. The products of resorcinol biodegradation were apparently 1, 4-cyclohexadiene, nonadecene, 2-heptadecanone, 1-isopropyl-2-methoxy-4-methylbenzene, hexadecanoic acid, 9-octadecenoic acid, phenol and 5-methyl-2-(1-methylethyl). Conclusions: The findings revealed thatPseudomonas sp. is able to degrade resorcinol. Because of being an indigenous organism, this isolate is more compatible with the climate of the northwest region of Iran and possibly will be used for degradation of other similar aromatic compounds.

  6. [Degradation characteristics of naphthalene with a Pseudomonas aeruginosa strain isolated from soil contaminated by diesel].

    Science.gov (United States)

    Liu, Wen-Chao; Wu, Bin-Bin; Li, Xiao-Sen; Lu, Dian-Nan; Liu, Yong-Min

    2015-02-01

    Abstract: A naphthalene-degrading bacterium (referred as HD-5) was isolated from the diesel-contaminated soil and was assigned to Pseudomonas aeruginosa according to 16S rDNA sequences analysis. Gene nah, which encodes naphthalene dioxygenase, was identified from strain HD-5 by PCR amplification. Different bioremediation approaches, including nature attenuation, bioaugmentation with strain Pseudomonas aeruginosa, biostimulation, and an integrated degradation by bioaugmentation and biostimulation, were evaluated for their effectiveness in the remediating soil containing 5% naphthalene. The degradation rates of naphthalene in the soil were compared among the different bioremediation approaches, the FDA and dehydrogenase activity in bioremediation process were measured, and the gene copy number of 16S rRNA and nah in soil were dynamically monitored using real-time PCR. It was shown that the naphthalene removal rate reached 71.94%, 62.22% and 83.14% in approaches of bioaugmentation (B), biostimulation(S) and integrated degradation composed of bioaugmentation and biostimulation (BS), respectively. The highest removal rate of naphthalene was achieved by using BS protocol, which also gives the highest FDA and dehydrogenase activity. The gene copy number of 16S rRNA and nah in soil increased by about 2.67 x 10(11) g(-1) and 8.67 x 10(8) g(-1) after 31 days treatment using BS protocol. Above-mentioned results also demonstrated that the screened bacterium, Pseudomonas aeruginosa, could grow well in naphthalene-contaminated soil and effectively degrade naphthalene, which is of fundamental importance for bioremediation of naphthalene-contaminated soil.

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

    NARCIS (Netherlands)

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

    2003-01-01

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

  8. Comparative evaluation of organic formulations of Pseudomonas ...

    African Journals Online (AJOL)

    An experiment was conducted in the laboratory and farm of the Department of Biotechnology, Gauhati University, to explore the potentiality of various organic formulations of Pseudomonas fluorescens (Pf) and to manage bacterial wilt disease of brinjal (Solanum melongena L.) under local conditions. Different organic ...

  9. NLF20: an antimicrobial peptide with therapeutic potential against invasive Pseudomonas aeruginosa infection.

    Science.gov (United States)

    Papareddy, Praveen; Kasetty, Gopinath; Kalle, Martina; Bhongir, Ravi K V; Mörgelin, Matthias; Schmidtchen, Artur; Malmsten, Martin

    2016-01-01

    Increasing resistance to antibiotics makes antimicrobial peptides interesting as novel therapeutics. Here, we report on studies of the peptide NLF20 (NLFRKLTHRLFRRNFGYTLR), corresponding to an epitope of the D helix of heparin cofactor II (HCII), a plasma protein mediating bacterial clearance. Peptide effects were evaluated by a combination of in vitro and in vivo methods, including antibacterial, anti-inflammatory and cytotoxicity assays, fluorescence and electron microscopy, and experimental models of endotoxin shock and Pseudomonas aeruginosa sepsis. The results showed that NLF20 displayed potent antimicrobial effects against the Gram-negative bacteria Escherichia coli and P. aeruginosa, the Gram-positive Bacillus subtilis and Staphylococcus aureus and the fungi Candida albicans and Candida parapsilosis. Importantly, this antimicrobial effect was retained in human blood, particularly for P. aeruginosa. Fluorescence and electron microscopy studies showed that the peptide exerted membrane-breaking effects. In an animal model of P. aeruginosa sepsis, NLF20 reduced bacterial levels, resulting in improved survival. Reduced mortality was also observed in experimental animal models of endotoxin shock, which was paralleled with modulated IFN-γ, IL-10 and coagulation responses. Together, these results indicate that functional epitopes of HCII may have therapeutic potential against bacterial infection. © The Author 2015. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  10. Aromatic Hydrocarbons: Degrading Bacteria in the Desert Soil of Kuwait

    International Nuclear Information System (INIS)

    Al-Gounaim, M.; Diab, A.; Al-Hilali, A.; Abu-Shady, A. Sattar

    2005-01-01

    Soil samples of different levels of oil pollutants were collected from Kuwait's Burgan Oil Field, near an oil lake. The samples represented, highly polluted (8.0% w/w), moderately polluted (2.1%-3.4%) and slightly polluted (2.1%-3.4%) and slightly polluted (0.5- 0.8%). The aromatic fractions of the collected samples were in the range of (0.21-2.57g/100g) soil. (GC) analysis of the aromatic fractions of the resolution of the different individual (PAHs) revealed the presence of (16) different (PAHs) resolved from the aromatic fraction of the highly polluted sample (S3). (15), (14) and (13) individual (PAHs) were identified soil samples (S5), (S2) and (S1, S4, S6) respectively. The most frequent (PAH) was indeno (1, 2, 3-c, d) pyrene (22.5%-45.11%) followed chrysene (13.6%-19.48%). Eight carcinogenic (PAHs) were resolved from the aromatic fractions of the polluted samples. Total carcinogenic (PAHs) recorded in this study were in this study were in the range of (11.53) (forS4) - (510.98) (for S3) ppm. The counts of (CFU) of aromatic degraders (AD) were in the range of (3x10) - (110x 10) (CFU/g) soil (with a percent of (2.2%-69.6%)). The results show that, higher counts of (AD) were recorded from a highly polluted sample (S3), followed by the moderately polluted samples; total of (51) bacteria, that gave presumptive positive biodegradation activities, were isolated and identified (45.1%) of them were isolated and identified. (45.1%) of them were isolated from the highly polluted sample (S3). Total of (13) different species were identified of which Micrococcus luteus was more frequent (23.5) followed by Bacillus licheniformis (19.6%) and Bacillus subtilis (11.8%). The three Pseudomonas species collectively were presented by (11.8%). Five different species proved to be of good activities, they are: Bacillus brevis, Bacillus lichenoformis, Pseudomonas aeruginosa, Pseudomonas stutzeri and Pseudomonas flourescens. The ability of five species and their mixture was

  11. Reclassification of Serpens flexibilis Hespell 1977 as Pseudomonas flexibilis comb. nov., with Pseudomonas tuomuerensis Xin et al. 2009 as a later heterotypic synonym.

    Science.gov (United States)

    Shin, Su-Kyoung; Hwang, Chung Yeon; Cho, Yong-Joon; Yi, Hana

    2015-12-01

    Serpens flexibilis was proposed in 1977 and approved in 1980 without the 16S rRNA gene sequence information. The sequence of S. flexibilis became available in 2010, after the publication of Pseudomonas tuomuerensis in 2009. Our preliminary phylogenetic analyses indicated that these two strains share high sequence similarity and therefore showed strong potential to be united into a single species. To clarify the taxonomic status of the two species, a polyphasic taxonomy study was conducted including whole genome sequencing. The value of average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) between the genome sequences of S. flexibilis ATCC 29606(T) and P. tuomuerensis JCM 14085(T) were 98.1% and 89.0%, respectively. The phenotypic and chemotaxonomic properties including enzymatic activities, substrate utilization profiles, and fatty acids, supported that the two taxa have no pronounced difference and should thus constitute a single species. Therefore, we propose to transfer Serpens flexibilis Hespell 1977 to the genus Pseudomonas as Pseudomonas flexibilis comb. nov. (type strain=ATCC 29606(T)), with Pseudomonas tuomuerensis Xin et al. 2009 as a later heterotypic synonym of Pseudomonas flexibilis. Copyright © 2015 Elsevier GmbH. All rights reserved.

  12. Extracellular toxins of pseudomonas aeruginosa. Pt. 4

    International Nuclear Information System (INIS)

    Obernesser, H.J.; Doering, G.

    1982-01-01

    A sensitive and specific solid phase radioimmunoassay (RIA) for detection of the elastase (Ela) of Pseudomonas aeruginosa (PA) was developed and the RIA was used to assay 10 PA strains of various origin and serotype. A great strain variability of Ela production was found which different from 94.1 to 0.1 μg per ml of culture supernatant fluid (CSF). The Ela and alkaline protease (AP) concentrations were converted to proteolytic activity and combined. The sum of the calculated enzymatic values of Ela and AP correlated well with the experimentally determined values of total proteolytic activity of the CSF. (orig.) [de

  13. Study on the efficiency of the two phase partitioning stirred tank bioreactor on the toluene filtration from the airstream by Pseudomonas putida via

    Directory of Open Access Journals (Sweden)

    2013-02-01

    Full Text Available Introduction: There are different methods for controlling gaseous pollutants formed from air pollution sources that one of the most economical and efficient of them, is bio-filtration. The purpose of this study is Toluene removal from airstream by using the pure Pseudomonas putida bacteria as a fluidized bed in a two phase partitioning stirred tank bioreactor.Toluene ( Metyle benzene is one of the aromatic compounds which uses as a chemical solvent.low to moderate concentration of Toluene causes fatigue, dizziness, weakness,unbalance behaviour, memory loss, insomnia, loss of appetite, loss of vision and hearing. .Material and Method: In this experimental study at first, pure Pseudomonas putida in an aqueous phase containing nutrients and trace elements solution was duplicated and accustomed with Toluene. then solution contained microorganisms with 10% silicon oil was entered to bioreactor. The amount of CO2 and pollutant concentrations in the entrance and exhaust of bioreactor containing Pseudomonas putida was studied during 17 days for each variable. .Result: Experimental findings showed that in the 0.06 m3/h and 0.12 m3/h flow rate, the efficiency of bioreactor containing Pseudomonas putida in the concentration ranges of 283 Mg/m3 to 4710 Mg/m3 was at least 97% and 25% respectively. Statistical analysis (ANOVA showed that in two flow rates of 0.06 m3/h and 0.12 m3/h removal efficiency and mineralization percentage had significant differences .(Pvalue =0.01. .Conclusion: Achieving high efficiencies in pollutants removal was because of the prepared optimum conditions for Pseudomonas putida in the two phase partitioning stirred tank bioreactor with 10% organic phase.

  14. Draft Genome Sequence of an Invasive Multidrug-Resistant Strain, Pseudomonas aeruginosa BK1, Isolated from a Keratitis Patient

    KAUST Repository

    Jeganathan, Lakshmi Priya

    2014-03-27

    Pseudomonas aeruginosa infections are difficult to treat due to the presence of a multitude of virulence factors and antibiotic resistance. Here, we report the draft genome sequence of P. aeruginosa BK1, an invasive and multidrug-resistant strain, isolated from a bacterial keratitis patient in southern India.

  15. Biosurfactants in plant-Pseudomonas interactions and their importance to biocontrol.

    Science.gov (United States)

    D'aes, Jolien; De Maeyer, Katrien; Pauwelyn, Ellen; Höfte, Monica

    2010-06-01

    Production of biosurfactants is a common feature in bacteria, and in particular in plant-associated species. These bacteria include many plant beneficial and plant pathogenic Pseudomonas spp., which produce primarily cyclic lipopeptide and rhamnolipid type biosurfactants. Pseudomonas-derived biosurfactants are involved in many important bacterial functions. By modifying surface properties, biosurfactants can influence common traits such as surface motility, biofilm formation and colonization. Biosurfactants can alter the bio-availability of exogenous compounds, such as nutrients, to promote their uptake, and of endogenous metabolites, including phenazine antibiotics, resulting in an enhanced biological activity. Antibiotic activity of biosurfactants towards microbes could play a role in intraspecific competition, self-defence and pathogenesis. In addition, bacterial surfactants can affect plants in different ways, either protecting them from disease, or acting as a toxin in a plant-pathogen interaction. Biosurfactants are involved in the biocontrol activity of an increasing number of Pseudomonas strains. Consequently, further insight into the roles and activities of surfactants produced by bacteria could provide means to optimize the use of biological control as an alternative crop protection strategy. © 2009 Society for Applied Microbiology and Blackwell Publishing Ltd.

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

    Directory of Open Access Journals (Sweden)

    Anoop M

    2017-05-01

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

  17. Isolation and characterization of a new Pseudomonas-related strain ...

    African Journals Online (AJOL)

    % with Pseudomonas putida ()AB680847). The phylogenetic tree formed by 16S rDNA sequences from both strain SKDP-1 and its most related bacteria also proved strain SKDP-1 to be one member of the genus Pseudomonas. Strain SKDP-1 ...

  18. Caenorhabditis elegans reveals novel Pseudomonas aeruginosa virulence mechanism

    NARCIS (Netherlands)

    Utari, Putri Dwi; Quax, Wim J.

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

  19. Characterization of Pseudomonas pathovars isolated from rosaceous fruit trees in East Algeria.

    Science.gov (United States)

    Harzallah, D; Sadallah, S; Larous, L

    2004-01-01

    A survey of bacterial diseases due to Pseudomonas on rosaceous fruit trees was conducted. In forty two orchards located in the Constantine region ( East Algeria). Pseudomonas isolates were identified on the bases of their cultural and biochemical characteristics . A total of fifty nine phytopathogenic bacteria were isolated from diseased pome and stone fruit trees. Thirty one strains comparable to Pseudomonas syringae pv. syringae were isolated from cherry (Prunus avium L.), plum (P. domestica L.), apricot (P. armeniaca L.), almond (P. dulcis L.) and pear trees (Pirus communis L.); sixteen strains comparable to Pseudomonas syringae pv. morsprunorum were obtained from samples of cherry and plum. Twelve strains of Pseudomonas viridiflava were isolated from cherry, apricot and peach (Prunus persica L.).

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

    African Journals Online (AJOL)

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

  1. Aspergillus triggers phenazine production in Pseudomonas aeruginosa

    DEFF Research Database (Denmark)

    Jensen, Britt Guillaume; Jelsbak, Lars; Søndergaard, Ib

    in the contact area of A. niger, A. flavus, A. oryzae, but not A. fumigatus. In addition, other metabolites with UV chromophores similar to the phenazines were only found in the contact zone between Aspergillus and Pseudomonas. No change in secondary metabolite profiles were seen for the Aspergilli, when......Objectives: Pseudomonas aeruginosa is an opportunistic human pathogen, commonly infecting cystic fibrosis (CF) patients. Aspergilli, especially Aspergillus fumigatus, are also frequently isolated from CF patients. Our aim was to examine the possible interaction between P. aeruginosa and different...... Aspergillus species. Methods: A suspension of fungal spores was streaked onto WATM agar plates. After 24 hours incubation at 37 °C, a P. aeruginosa overnight culture was streaked out perpendicular to the fungal streak. The plates were incubated at 37 °C for five days, examined and plugs were extracted...

  2. Pseudomonas sp. BUP6, a novel isolate from Malabari goat produces an efficient rhamnolipid type biosurfactant.

    Science.gov (United States)

    Priji, Prakasan; Sajith, Sreedharan; Unni, Kizhakkepowathial Nair; Anderson, Robin C; Benjamin, Sailas

    2017-01-01

    This study describes the characteristics of a biosurfactant produced by Pseudomonas sp. BUP6, a rumen bacterium, and optimization of parameters required for its production. Initial screening of five parameters (pH, temperature, agitation, incubation, and substrate concentration) was carried out employing Plackett-Burman design, which reduced the number of parameters to 3 (pH, temperature, and incubation) according to their significance on the yield of biosurfactant. A suitable statistical model for the production of biosurfactant by Pseudomonas sp. BUP6 was established according to Box-Behnken design, which resulted in 11% increase (at pH 7, 35 °C, incubation 75 h) in the yield (2070 mg L -1 ) of biosurfactant. The biosurfactant was found stable at a wide range of pH (3-9) with 48 mg L -1 critical micelle concentration; and maintained over 90% of its emulsification ability even after boiling and in presence of sodium chloride (0.5%). The highest cell hydrophobicity (37%) and emulsification (69%) indices were determined with groundnut oil and kerosene, respectively. The biosurfactant was found to inhibit the growth and adhesion of E. coli and S. aureus significantly. From the phytotoxicity studies, the biosurfactant did not show any adverse effect on the germinating seeds of rice and green gram. The structural characterization of biosurfactant employing orcinol method, thin layer chromatography and FT-IR indicated that it is a rhamnolipid (glycolipid). Thus, Pseudomonas sp. BUP6, a novel isolate from Malabari goat is demonstrated as a producer of an efficient rhamnolipid type biosurfactant suitable for application in various industries. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Enzymatic characterization and gene identification of aconitate isomerase, an enzyme involved in assimilation of trans-aconitic acid, from Pseudomonas sp. WU-0701.

    Science.gov (United States)

    Yuhara, Kahori; Yonehara, Hiromi; Hattori, Takasumi; Kobayashi, Keiichi; Kirimura, Kohtaro

    2015-11-01

    trans-Aconitic acid is an unsaturated organic acid that is present in some plants such as soybean and wheat; however, it remains unclear how trans-aconitic acid is degraded and/or assimilated by living cells in nature. From soil, we isolated Pseudomonas sp. WU-0701 assimilating trans-aconitic acid as a sole carbon source. In the cell-free extract of Pseudomonas sp. WU-0701, aconitate isomerase (AI; EC 5.3.3.7) activity was detected. Therefore, it seems likely that strain Pseudomonas sp. WU-0701 converts trans-aconitic acid to cis-aconitic acid with AI, and assimilates this via the tricarboxylic acid cycle. For the characterization of AI from Pseudomonas sp. WU-0701, we performed purification, determination of enzymatic properties and gene identification of AI. The molecular mass of AI purified from cell-free extract was estimated to be ~ 25 kDa by both SDS/PAGE and gel filtration analyses, indicating that AI is a monomeric enzyme. The optimal pH and temperature of purified AI for the reaction were 6.0 °C and 37 °C, respectively. The gene ais encoding AI was cloned on the basis of the N-terminal amino acid sequence of the protein, and Southern blot analysis revealed that only one copy of ais is located on the bacterial genome. The gene ais contains an ORF of 786 bp, encoding a polypeptide of 262 amino acids, including the N-terminal 22 amino acids as a putative periplasm-targeting signal peptide. It is noteworthy that the amino acid sequence of AI shows 90% and 74% identity with molybdenum ABC transporter substrate-binding proteins of Pseudomonas psychrotolerans and Xanthomonas albilineans, respectively. This is the first report on purification to homogeneity, characterization and gene identification of AI. The nucleotide sequence of ais described in this article is available in the DDBJ/EMBL/GenBank nucleotide sequence databases under the Accession No. LC010980. © 2015 FEBS.

  4. Biotransformation of isoeugenol to vanillin by Pseudomonas putida IE27 cells.

    Science.gov (United States)

    Yamada, Mamoru; Okada, Yukiyoshi; Yoshida, Toyokazu; Nagasawa, Toru

    2007-01-01

    The ability to produce vanillin and/or vanillic acid from isoeugenol was screened using resting cells of various bacteria. The vanillin- and/or vanillic-acid-producing activities were observed in strains belonging to the genera Achromobacter, Aeromonas, Agrobacerium, Alcaligenes, Arthrobacter, Bacillus, Micrococcus, Pseudomonas, Rhodobacter, and Rhodococcus. Strain IE27, a soil isolate showing the highest vanillin-producing activity, was identified as Pseudomonas putida. We optimized the culture and reaction conditions for vanillin production from isoeugenol using P. putida IE27 cells. The vanillin-producing activity was induced by adding isoeugenol to the culture medium but not vanillin or eugenol. Under the optimized reaction conditions, P. putida IE27 cells produced 16.1 g/l vanillin from 150 mM isoeugenol, with a molar conversion yield of 71% at 20 degrees C after a 24-h incubation in the presence of 10% (v/v) dimethyl sulfoxide.

  5. 40 CFR 180.1261 - Xanthomonas campestris pv. vesicatoria and Pseudomonas syringae pv. tomato specific Bacteriophages.

    Science.gov (United States)

    2010-07-01

    ... and Pseudomonas syringae pv. tomato specific Bacteriophages. 180.1261 Section 180.1261 Protection of.... vesicatoria and Pseudomonas syringae pv. tomato specific Bacteriophages. An exemption from the requirement of... syringae pv. tomato specific bacteriophages in or on pepper and tomato. [74 FR 26536, June 3, 2009] ...

  6. Enhancement of Biogas Production from Bakery Waste by Pseudomonas aeruginosa

    OpenAIRE

    S. Potivichayanon; T. Sungmon; W. Chaikongmao; S. Kamvanin

    2011-01-01

    Production of biogas from bakery waste was enhanced by additional bacterial cell. This study was divided into 2 steps. First step, grease waste from bakery industry-s grease trap was initially degraded by Pseudomonas aeruginosa. The concentration of byproduct, especially glycerol, was determined and found that glycerol concentration increased from 12.83% to 48.10%. Secondary step, 3 biodigesters were set up in 3 different substrates: non-degraded waste as substrate in fir...

  7. Clinical utilization of genomics data produced by the international Pseudomonas aeruginosa consortium

    DEFF Research Database (Denmark)

    Freschi, Luca; Jeukens, Julie; Kukavica-Ibrulj, Irena

    2015-01-01

    The International Pseudomonas aeruginosa Consortium is sequencing over 1000 genomes and building an analysis pipeline for the study of Pseudomonas genome evolution, antibiotic resistance and virulence genes. Metadata, including genomic and phenotypic data for each isolate of the collection, are a...... implicated in human and animal infections, understand how patients become infected and how the infection evolves over time as well as identify prognostic markers for better evidence-based decisions on patient care....

  8. Presence of VIM-Positive Pseudomonas Species in Chickens and Their Surrounding Environment.

    Science.gov (United States)

    Zhang, Rongmin; Liu, Zhihai; Li, Jiyun; Lei, Lei; Yin, Wenjuan; Li, Mei; Wu, Congming; Walsh, Timothy R; Wang, Yang; Wang, Shaolin; Wu, Yongning

    2017-07-01

    Metallo-β-lactamase gene bla VIM was identified on the chromosome of four Pseudomonas sp. isolates from a chicken farm, including one Pseudomonas aeruginosa isolate from a swallow ( Yanornis martini ), one Pseudomonas putida isolate from a fly, and two P. putida isolates from chickens. The four isolates shared two variants of bla VIM -carrying genomic contexts that resemble the corresponding regions of clinical metallo-β-lactamase-producing Pseudomonas spp. Our study suggests that the surveillance of carbapenemase-producing bacteria in livestock and their surrounding environment is urgently needed. Copyright © 2017 American Society for Microbiology.

  9. ANOMALOUS BLUE COLOURING OF MOZZARELLA CHEESE INTENTIONALLY CONTAMINATED WITH PIGMENT PRODUCING STRAINS OF PSEUDOMONAS FLUORESCENS

    Directory of Open Access Journals (Sweden)

    P. Sechi

    2011-04-01

    Full Text Available In summer 2010 a large outbreak of anomalous blue coloration of mozzarella cheese was recorded in Italy and some northern European countries. Official laboratory analysis and health authorities linked the outbreak to the contamination of processing water with strains of Pseudomonas fluorescens, although several expert raised the question of how to unequivocally link the blue coloring to the presence of the micro-organism. In an attempt to set-up a method to determine whether a given Pseudomonas spp. strain is responsible of the defect, an in vitro system for the evaluation of blue colouring of mozzarella cheese intentionally contaminated with strains of Pseudomonas fluorescens. was developed The system is aimed to ascertain whether P. fluorescens strains, isolated from mozzarella cheese with anomalous blue coloration, are able to reproduce the blue coloration under controlled experimental condition. 96 trials of experimental inoculation of mozzarella cheese in different preservation liquids, were conducted using various suspension of Pseudomonas spp. (P. fluorescens ATCC 13525, P. fluorescens CFBP 3150, one P. fluorescens field strain isolated from blue-colored mozzarella cheese and P. aeruginosa ATCC 10145 as positive control at different concentrations and incubated at different temperatures. Growth curve of all Pseudomonas spp. strains tested demonstrated that after three days of incubation the concentration was generally higher than 106 CFU/g of mozzarella cheese incubated in Tryptic Soy Broth (TSB, and higher than 105 CFU/g of mozzarella cheese incubated in preservation liquid. All mozzarella cheeses inoculated with the field strain of Pseudomonas fluorescens showed the characteristic anomalous blue coloration, which is often associated with Pseudomonas fluorescens contamination of water used during mozzarella cheesemaking. With the proposed system, which enabled a considerable amount of samples to be analysed under controlled experimental

  10. Growth of Pseudomonas spp. in cottage cheese

    DEFF Research Database (Denmark)

    Østergaard, Nina Bjerre; Dalgaard, Paw

    Cottage cheese is a mixture of cheese curd with pH 4.5-4.8 and an uncultured or cultured cream dressing with a pH as high as 7.0. This results in a final product with microenvironments and a bulk pH of about 4.8 to 5.5. As for other lightly preserved foods microbial contamination and growth...... of spoilage microorganisms in cottage cheese can cause undesirable alterations in flavour, odour, appearance and texture. Contamination and growth of psychrotolerant pseudomonads including Pseudomonas fragi and Pseudomonas putida has been reported for cottage cheese but the influence of these bacteria...... on product spoilage and shelf-life remains poorly described. The present study used a quantitative microbial ecology approach to model and predict the effect of product characteristics and storage conditions on growth of psychrotolerant pseudomonads in cottage cheese. The effect of temperature (5-15˚C) and p...

  11. Molecular detection of an atypical, highly resistant, clonal Pseudomonas aeruginosa isolate in cystic fibrosis patients.

    LENUS (Irish Health Repository)

    Keating, Deirdre

    2013-03-01

    The identification of Pseudomonas aeruginosa (P. aeruginosa) isolates in sputum from cystic fibrosis (CF) patients can be challenging due to the multitude of phenotypic changes isolates undergo during adaptation to the microenvironment of the CF lung.

  12. Peritoneal dialysis-related peritonitis caused by Pseudomonas species: Insight from a post-millennial case series.

    Science.gov (United States)

    Lu, Wanhong; Kwan, Bonnie Ching-Ha; Chow, Kai Ming; Pang, Wing-Fai; Leung, Chi Bon; Li, Philip Kam-To; Szeto, Cheuk Chun

    2018-01-01

    Pseudomonas peritonitis is a serious complication of peritoneal dialysis (PD). However, the clinical course of Pseudomonas peritonitis following the adoption of international guidelines remains unclear. We reviewed the clinical course and treatment response of 153 consecutive episodes of PD peritonitis caused by Pseudomonas species from 2001 to 2015. Pseudomonas peritonitis accounted for 8.3% of all peritonitis episodes. The bacteria isolated were resistant to ceftazidime in 32 cases (20.9%), and to gentamycin in 18 cases (11.8%). In 20 episodes (13.1%), there was a concomitant exit site infection (ESI); in another 24 episodes (15.7%), there was a history of Pseudomonas ESI in the past. The overall primary response rate was 53.6%, and complete cure rate 42.4%. There was no significant difference in the complete cure rate between patients who treated with regimens of 3 and 2 antibiotics. Amongst 76 episodes (46.4%) that failed to respond to antibiotics by day 4, 37 had immediate catheter removal; the other 24 received salvage antibiotics, but only 6 achieved complete cure. Antibiotic resistance is common amongst Pseudomonas species causing peritonitis. Adoption of the treatment guideline leads to a reasonable complete cure rate of Pseudomonas peritonitis. Treatment with three antibiotics is not superior than the conventional two antibiotics regimen. When there is no clinical response after 4 days of antibiotic treatment, early catheter removal should be preferred over an attempt of salvage antibiotic therapy.

  13. Nosocomial outbreak of Pseudomonas aeruginosa endophthalmitis.

    Science.gov (United States)

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

    2006-11-01

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

  14. Occurrence and antibiotic susceptibility of fish bacteria isolated from Oreochromis niloticus (Nile tilapia and Clarias gariepinus (African catfish in Uganda

    Directory of Open Access Journals (Sweden)

    S. P. Wamala

    2018-02-01

    Full Text Available Abstract The intention of this study was to identify the bacterial pathogens infecting Oreochromis niloticus (Nile tilapia and Clarias gariepinus (African catfish, and to establish the antibiotic susceptibility of fish bacteria in Uganda. A total of 288 fish samples from 40 fish farms (ponds, cages, and tanks and 8 wild water sites were aseptically collected and bacteria isolated from the head kidney, liver, brain and spleen. The isolates were identified by their morphological characteristics, conventional biochemical tests and Analytical Profile Index test kits. Antibiotic susceptibility of selected bacteria was determined by the Kirby-Bauer disc diffusion method. The following well-known fish pathogens were identified at a farm prevalence of; Aeromonas hydrophila (43.8%, Aeromonas sobria (20.8%, Edwardsiella tarda (8.3%, Flavobacterium spp. (4.2% and Streptococcus spp. (6.3%. Other bacteria with varying significance as fish pathogens were also identified including Plesiomonas shigelloides (25.0%, Chryseobacterium indoligenes (12.5%, Pseudomonas fluorescens (10.4%, Pseudomonas aeruginosa (4.2%, Pseudomonas stutzeri (2.1%, Vibrio cholerae (10.4%, Proteus spp. (6.3%, Citrobacter spp. (4.2%, Klebsiella spp. (4.2% Serratia marcescens (4.2%, Burkholderia cepacia (2.1%, Comamonas testosteroni (8.3% and Ralstonia picketti (2.1%. Aeromonas spp., Edwardsiella tarda and Streptococcus spp. were commonly isolated from diseased fish. Aeromonas spp. (n = 82 and Plesiomonas shigelloides (n = 73 were evaluated for antibiotic susceptibility. All isolates tested were susceptible to at-least ten (10 of the fourteen antibiotics evaluated. High levels of resistance were however expressed by all isolates to penicillin, oxacillin and ampicillin. This observed resistance is most probably intrinsic to those bacteria, suggesting minimal levels of acquired antibiotic resistance in fish bacteria from the study area. To our knowledge, this is the first study to

  15. Soil mixture composition alters Arabidopsis susceptibility to Pseudomonas syringae infection

    Science.gov (United States)

    Pseudomonas syringae is a Gram-negative bacterial pathogen that causes disease on more than 100 different plant species, including the model plant Arabidopsis thaliana. Dissection of the Arabidopsis thaliana-Pseudomonas syringae pathosystem has identified many factors that contribute to successful ...

  16. Migration of bacteria in compacted clay-based material

    Energy Technology Data Exchange (ETDEWEB)

    Stroes-Gascoyne, S; Lucht, L M; Oscarson, D W; Dixon, D A; Hume, H B; Miller, S H

    1997-11-01

    Buffer (a mixture of 50 wt.% Na-bentonite and 50 wt.% silica sand compacted to a dry density of about 1.68 g/cm{sup 3}) would surround waste containers in a Canadian nuclear fuel waste disposal vault. The initial heat and radiation output from these containers would likely prevent significant microbial activity at or near container surfaces for some time after disposal, thereby limiting effects such as microbially-influenced corrosion. Microbial repopulation of buffer as conditions improve with time may not occur because of its small pores. Experiments with irradiated buffer plugs (2.2 cm in diameter and 5-cm long; at dry densities of 1.68 and 1.80 g/cm{sup 3}) were performed to assess the ability of microbes to migrate in buffer. Viable bacteria (Pseudomonas stutzeri), in a suitable growth medium, were brought in contact with one end of the plugs. After 2, 4, 8, 16 and 20 weeks, the plugs were sectioned and tested for moisture content and viable bacteria. Results showed that the plugs were slowly wetting and that moisture levels were sufficient to sustain microbes. No evidence of P. stutzeri was found, however, in all but the first 0.5 cm of the plugs (smallest distance sampled) over a 20-week period. The results suggest that microbial migration in buffer is limited or even completely prevented because of its relatively small pores. (author)

  17. Migration of bacteria in compacted clay-based material

    International Nuclear Information System (INIS)

    Stroes-Gascoyne, S.; Lucht, L.M.; Oscarson, D.W.; Dixon, D.A.; Hume, H.B.; Miller, S.H.

    1997-11-01

    Buffer (a mixture of 50 wt.% Na-bentonite and 50 wt.% silica sand compacted to a dry density of about 1.68 g/cm 3 ) would surround waste containers in a Canadian nuclear fuel waste disposal vault. The initial heat and radiation output from these containers would likely prevent significant microbial activity at or near container surfaces for some time after disposal, thereby limiting effects such as microbially-influenced corrosion. Microbial repopulation of buffer as conditions improve with time may not occur because of its small pores. Experiments with irradiated buffer plugs (2.2 cm in diameter and 5-cm long; at dry densities of 1.68 and 1.80 g/cm 3 ) were performed to assess the ability of microbes to migrate in buffer. Viable bacteria (Pseudomonas stutzeri), in a suitable growth medium, were brought in contact with one end of the plugs. After 2, 4, 8, 16 and 20 weeks, the plugs were sectioned and tested for moisture content and viable bacteria. Results showed that the plugs were slowly wetting and that moisture levels were sufficient to sustain microbes. No evidence of P. stutzeri was found, however, in all but the first 0.5 cm of the plugs (smallest distance sampled) over a 20-week period. The results suggest that microbial migration in buffer is limited or even completely prevented because of its relatively small pores. (author)

  18. ANTAGONISTIC POTENTIAL OF FLUORESCENT Pseudomonas ...

    African Journals Online (AJOL)

    Prof. Adipala Ekwamu

    GROWTH OF TOMATO CHALLENGED WITH PHTOPATHOGENS ... This study focused on the antagonistic potential of fluorescent Pseudomonas in vitro, and its inoculation effect on growth .... the 5 days old culture in starch agar with Lugol's.

  19. Pseudomonas cepacia adherence to respiratory epithelial cells is enhanced by Pseudomonas aeruginosa

    International Nuclear Information System (INIS)

    Saiman, L.; Cacalano, G.; Prince, A.

    1990-01-01

    Pseudomonas aeruginosa and Pseudomonas cepacia are both opportunistic pathogens of patients with cystic fibrosis. The binding characteristics of these two species were compared to determine if they use similar mechanisms to adhere to respiratory epithelial cells. P. cepacia 249 was shown to be piliated, but there was no detectable homology between P. aeruginosa pilin gene probes and P. cepacia genomic DNA. P. cepacia and P. aeruginosa did not appear to compete for epithelial receptors. In the presence of purified P. aeruginosa pili, the adherence of 35S-labeled strain 249 to respiratory epithelial monolayers was unaffected, while that of P. aeruginosa PAO1 was decreased by 55%. The binding of P. cepacia 249 and 715j was increased by 2.4-fold and 1.5-fold, respectively, in the presence of an equal inoculum of PAO1. Interbacterial agglutination contributed to the increased adherence of P. cepacia, as the binding of 249 was increased twofold in the presence of irradiated PAO1. PAO1 exoproducts had a marked effect in enhancing the ability of the P. cepacia strains to adhere to the epithelial monolayers. A PAO1 supernatant increased the binding of 249 by eightfold and that of 715j by fourfold. Thus, there appears to be a synergistic relationship between P. aeruginosa and P. cepacia in which PAO1 exoproducts modify the epithelial cell surface, exposing receptors and facilitating increased P. cepacia attachment

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

    Science.gov (United States)

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

    2014-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Garry Laverty

    2014-07-01

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

  2. Pseudomonas aeruginosa: evaluation of pathogen burden and drug-resistance trends in a tertiary care hospital

    International Nuclear Information System (INIS)

    Saeed, M.; Hussain, S.; Ahmad, A.

    2018-01-01

    To evaluate the pathogen burden and antibiotic-resistance trends of Pseudomonas aeruginosa among hospitalised patients at a tertiary care hospital. Study Design:Retrospective, hospital record-based, cross-sectional study. Place and Duration of Study:Microbiology Laboratory, Allama Iqbal Medical College/Jinnah Hospital, Lahore, from January 2014 to December 2016. Methodology:A total of 5,960 samples were collected from clinically suspected cases of bacterial infections, admitted to the hospital. Microbial identification and antibiotic susceptibility pattern were carried out and analysed. Results:Out of a total of 5,960 samples, Pseudomonas aeruginosawas isolated from 1,268 (21.2%) specimens. Department-wise isolation rate was n=600 (42.9%), n=268 (15.4%), n=201 (12.6%), and n=199 (16.0%) from intensive care unit (ICU), surgical units, medical units, and Gynae wards, respectively (p<0.0001). Sample-wise isolation rate was, wound swabs n=448 (35%), urine n=356 (28%), sputum n=187 (14 %), tracheal aspirate n=127 (10%), blood n=99 (7%), and broncho-alveolar lavage n=51 (4%) (p<0.0001). Drug-resistance pattern showed low rates for carbapenems (meropenem n=440 (35%), Imipenem n=436 (34%) and beta-lactam + beta-lactamase inhibitor combination (piperacillin+ tazobactam n=437 (34%) while alarming rates were observed for cephalosporins (ceftazidime n=716 (56%), fluoroquinolones (ciprofloxacin n=690 (54%), cefoperazone+sulbactam n=685 (54%), aminoglycosides (gentamicin, n=669 (53%), amikacin n=608 (48%), and monobactams (aztreonam n=666 (52%). Decreasing trend was observed only for amikacin 63% to 37%, aztreonam showed similar pattern throughout, while there was an increasing trend of drug resistance in all groups of antibiotics. Conclusion:Emerging drug-resistant strains of Pseudomonas aeruginosaare probably linked to the injudicious use of antibiotics, leading to ineffective empirical therapy. Therefore, we suggest that culture and antimicrobial susceptibility testing should

  3. Ciprofloxacin susceptibility of Pseudomonas aeruginosa isolates from keratitis

    DEFF Research Database (Denmark)

    Lomholt, JA; Kilian, Mogens

    2003-01-01

    keratitis, endophthalmitis, contact lens associated red eye (CLARE), and contact lens storage cases showed MIC values below 1 mg/l. Several allelic forms of gyrA and a single variation in the mexR gene product were detected in 10 ciprofloxacin susceptible strains. CONCLUSIONS: The vast majority of eye......AIM: To examine the ciprofloxacin susceptibility of 106 Pseudomonas aeruginosa eye isolates from the United Kingdom, Denmark, India, the United States, and Australia, and to determine the molecular mechanisms of resistance. METHODS: Ciprofloxacin susceptibility was tested by an agar dilution method...... isolates of P aeruginosa from European countries are fully susceptible to ciprofloxacin and the concentration of ciprofloxacin eye drops used for local treatment (3000 mg/l) exceeds MIC values for strains recorded as resistant. Mutations in more than one target gene were associated with higher MIC values....

  4. Ciprofloxacin susceptibility of Pseudomonas aeruginosa isolates from keratitis

    DEFF Research Database (Denmark)

    Lomholt, JA; Kilian, Mogens

    2003-01-01

    AIM: To examine the ciprofloxacin susceptibility of 106 Pseudomonas aeruginosa eye isolates from the United Kingdom, Denmark, India, the United States, and Australia, and to determine the molecular mechanisms of resistance. METHODS: Ciprofloxacin susceptibility was tested by an agar dilution method...... keratitis, endophthalmitis, contact lens associated red eye (CLARE), and contact lens storage cases showed MIC values below 1 mg/l. Several allelic forms of gyrA and a single variation in the mexR gene product were detected in 10 ciprofloxacin susceptible strains. CONCLUSIONS: The vast majority of eye...... isolates of P aeruginosa from European countries are fully susceptible to ciprofloxacin and the concentration of ciprofloxacin eye drops used for local treatment (3000 mg/l) exceeds MIC values for strains recorded as resistant. Mutations in more than one target gene were associated with higher MIC values....

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

    DEFF Research Database (Denmark)

    Fluge, G; Ojeniyi, B; Høiby, N

    2001-01-01

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

  6. 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.

  7. PseudoMLSA: a database for multigenic sequence analysis of Pseudomonas species

    Directory of Open Access Journals (Sweden)

    Lalucat Jorge

    2010-04-01

    Full Text Available Abstract Background The genus Pseudomonas comprises more than 100 species of environmental, clinical, agricultural, and biotechnological interest. Although, the recommended method for discriminating bacterial species is DNA-DNA hybridisation, alternative techniques based on multigenic sequence analysis are becoming a common practice in bacterial species discrimination studies. Since there is not a general criterion for determining which genes are more useful for species resolution; the number of strains and genes analysed is increasing continuously. As a result, sequences of different genes are dispersed throughout several databases. This sequence information needs to be collected in a common database, in order to be useful for future identification-based projects. Description The PseudoMLSA Database is a comprehensive database of multiple gene sequences from strains of Pseudomonas species. The core of the database is composed of selected gene sequences from all Pseudomonas type strains validly assigned to the genus through 2008. The database is aimed to be useful for MultiLocus Sequence Analysis (MLSA procedures, for the identification and characterisation of any Pseudomonas bacterial isolate. The sequences are available for download via a direct connection to the National Center for Biotechnology Information (NCBI. Additionally, the database includes an online BLAST interface for flexible nucleotide queries and similarity searches with the user's datasets, and provides a user-friendly output for easily parsing, navigating, and analysing BLAST results. Conclusions The PseudoMLSA database amasses strains and sequence information of validly described Pseudomonas species, and allows free querying of the database via a user-friendly, web-based interface available at http://www.uib.es/microbiologiaBD/Welcome.html. The web-based platform enables easy retrieval at strain or gene sequence information level; including references to published peer

  8. Radionuclide and heavy metal biosorption by Pseudomonas biomass

    International Nuclear Information System (INIS)

    Sar, Pinaki; D'Souza, S.F.; Kazy, Sufia K.; Singh, S.P.

    2001-01-01

    Biosorptive metal (nickel and copper) and radionuclide (uranium) uptake capacity of two Pseudomonas strains was investigated in order to develop biotechnological strategies for toxic metals remediation. Lyophilized Pseudomonas biomass showed a very high uranium loading of 541 mg g -1 dry wt. Compared to this, the other bacterial strain of Pseudomonas aeruginosa used for nickel and copper removal yielded a maximum value of 265 mg g -1 and 137 mg g -1 respectively. Cation binding by both the biomass was fast saturating, pH -dependent process with optimum pH for U, Cu and Ni was pH 5.0, 7.0 and 8.0, respectively. In bimetallic combination, U sorption was inhibited only by Fe 3+ , Al 3+ and Cu 2+ suggesting a selective cation binding by the Pseudomonas biomass. In case of Ni and Cu, presence of Na, K or Ca increased the metal binding while Cd and Pb was antagonistic. Mineral acids could recover more than 75% (on average) of sorbed Ni or Cu. Noticeably, uranium and copper desorption was specifically high (88-90%) with sodium carbonate while calcium carbonate showed a good result for nickel. The overall data are in favour of deployment of the test biomass as efficient metal/radionuclide removal/recovery system. (author)

  9. 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.

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

    Directory of Open Access Journals (Sweden)

    R. Satheeskumar

    2013-10-01

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

  11. 40 CFR 180.1145 - Pseudomonas syringae; exemption from the requirement of a tolerance.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Pseudomonas syringae; exemption from... FOOD Exemptions From Tolerances § 180.1145 Pseudomonas syringae; exemption from the requirement of a tolerance. Pseudomonas syringae is exempted from the requirement of a tolerance on all raw agricultural...

  12. Interactions between biosurfactant-producing Pseudomonas and Phytophthora species

    OpenAIRE

    Tran, H.

    2007-01-01

    Fluorescent Pseudomonas bacteria produce a wide variety of antimicrobial metabolites, including soap-like compounds referred to as biosurfactants. The results of this thesis showed that biosurfactant-producing Pseudomonas bacteria are effective in controlling Phytophthora foot rot disease of black pepper in Vietnam and promote root and shoot development of the ‘King of Spices’. Biosurfactant-producing P. fluorescens strain SS101 was also effective in controlling tomato late blight caused by P...

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

    NARCIS (Netherlands)

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

    2003-01-01

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

  14. Cemaran Staphylococcus aureus dan Pseudomonas aerogenosa Pada Stetoskop dirumah Sakit

    Directory of Open Access Journals (Sweden)

    leka lutpiatina

    2017-10-01

    The result of the research was found contamination of Staphylococcus aureus and Pseudomonas aerogenosa on steteskop. The site home condition of the research data was 66.7% cleaned daily, the storage method was placed on the table 70% and the duration of using the set home more than 1 year as much as 70%. The conclusion of stethoscope at Banjarbaru Hospital was contaminated with Staphylococcus aureus by 70% and Pseudomonas aerogenosa by 17%. The suggestion of research can be continued by knowing the existence of Staphylococcus aureus resistant antibiotic and Pseudomonas aerogenous antibiotic resistant at steteskop at Hospital.

  15. Electron transfer patterns of the di-heme protein cytochrome c(4) from Pseudomonas stutzeri

    DEFF Research Database (Denmark)

    Raffalt, Anders Christer; Schmidt, L.; Christensen, Hans Erik Mølager

    2009-01-01

    protein structural mobility in the overall two-ET process. We suggest that conformational protein mobility blocks intramolecular interheme ET in bulk homogeneous solution but triggers opening of this gated ET channel in the electrochemical environment or in the membrane environment of natural respiratory...

  16. Development of a Pseudomonas aeruginosa Agmatine Biosensor

    OpenAIRE

    Gilbertsen, Adam; Williams, Bryan

    2014-01-01

    Agmatine, decarboxylated arginine, is an important intermediary in polyamine production for many prokaryotes, but serves higher functions in eukaryotes such as nitric oxide inhibition and roles in neurotransmission. Pseudomonas aeruginosa relies on the arginine decarboxylase and agmatine deiminase pathways to convert arginine into putrescine. One of the two known agmatine deiminase operons, aguBA, contains an agmatine sensitive TetR promoter controlled by AguR. We have discovered that this pr...

  17. Bioremediation of coractive blue dye by using Pseudomonas spp. isolated from the textile dye wastewater

    Science.gov (United States)

    Sunar, N. M.; Mon, Z. K.; Rahim, N. A.; Leman, A. M.; Airish, N. A. M.; Khalid, A.; Ali, R.; Zaidi, E.; Azhar, A. T. S.

    2018-04-01

    Wastewater released from the textile industry contains variety substances, mainly dyes that contains a high concentration of color and organic. In this study the potential for bacterial decolorization of coractive blue dye was examined that isolated from textile wastewater. The optimum conditions were determined for pH, temperature and initial concentration of the dye. The bacteria isolated was Pseudomonas spp. The selected bacterium shows high decolorization in static condition at an optimum of pH 7.0. The Pseudomonas spp. could decolorize coractive blue dye by 70% within 24 h under static condition, with the optimum of pH 7.0. Decolorization was confirmed by using UV-VIS spectrophotometer. This present study suggests the potential of Pseudomonas spp. as an approach in sustainable bioremediation that provide an efficient method for decolorizing coractive blue dye.

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

    DEFF Research Database (Denmark)

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

    2003-01-01

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

  19. Linear Alkylbenzene Sulfonate tolerance in bacteria isolated from sediment of tropical water bodies polluted with detergents

    Directory of Open Access Journals (Sweden)

    I.T Kehinde

    2008-12-01

    Full Text Available The discharge of untreated detergent-bearing waste introduces linear alkylbenzene sulfonates (LAS to the aquatic environment. The surfactant persists in some streams and rivers in Nigeria, some is adsorbed to suspended materials and end in the sediment of the receiving water bodies. In this study, bacteria isolated from sediments of some tropical detergent-effluent-polluted streams were tested for tolerance to LAS using the media dilution technique. LAS-tolerance was indicated by growth of the bacteria in the presence of the surfactant. The pH, concentrations of surfactant, population of heterotrophic bacteria and population of LAS-tolerant bacteria in the sediments were determined. A direct relationship (r= 0.9124 was found between the alkaline conditions (pH= 8.2-12.0 and high surfactant concentrations (45-132 mg/g in the sediment. The sediments harboured a high population and a wide variety of bacteria; the populations of viable heterotrophic bacteria (vHB: 2.9×10(5 to 1.2×10(7 cfu/g and LAS tolerant bacteria (LTB: 1.5×10(4 to 1.2×10(6 cfu/g had a direct relationship (r= 0.9500. An inverse relationship resulted between each of them and the concentration of surfactant in the sediment, r vHB/ LAS = -0.9303 and rLTB/ LAS = -0.9143, respectively. Twelve bacteria species were isolated from the sediment: Alcaligenes odorans, Bacillus subtilis, Burkholderia cepacia, Citrobacter freundii, Citrobacter diversus, Escherichia coli, Micrococcus luteus, Micrococcus albus, Pseudomonas putida, Pseudomonas stutzeri, Staphylococcus aureus and Streptococcus faecalis. Most of them were adapted to the surfactant with their maximum acceptable concentrations ranging between 0.03 and >1.0% (w/v. The sediments could serve as source of adapted organisms which can be used in bio-treatment of LAS-bearing waste. Rev. Biol. Trop. 56 (4:7-15. Epub 2008 December 12.La descarga de desechos que contienen detergentes liberan sulfonatos de alquibenceno lineal (LAS al

  20. 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...

  1. Efficacy of selected Pseudomonas strains for biocontrol of Rhizoctonia solani in potato

    Directory of Open Access Journals (Sweden)

    Moncef MRABET

    2014-01-01

    Full Text Available Thirty seven bacterial isolates from faba bean (Vicia faba L. root-nodules were screened for their antagonistic activity against eight Rhizoctonia solani strains isolated from infected potato (Solanum tuberosum L. tubers. Two bacterial strains (designated as Kl.Fb14 and S8.Fb11 gave 50% in vitro inhibition of R. solani mycelial growth. 16S rDNA sequence analysis indicated that strain Kl.Fb14 exhibited 99.5% identity with Pseudomonas moraviensis, and that S8.Fb11 exhibited 99.8% identity with Pseudomonas reinekei. Greenhouse trials in soil showed that strain S8.Fb11 reduced the percentage of sclerotia on potato tubers and amounts of tuber infection for the potato cultivars Spunta and Nicola. In a field trial conducted in South Tunisia, infection with R. solani reduced potato yield by approximately 40% for ‘Spunta’ and 17% for ‘Nicola’; about 20% of the total tuber production was severely infected. However, when potato tubers were treated with strain S8.Fb11 prior to sowing, disease incidence was reduced to 6% of total production with low infection levels; potato yield was enhanced by about 6 kg per 10 m row in comparison to R. solani infected plants. The second selected Pseudomonas sp. (strain Kl.Fb14 did not affect either the levels of sclerotia on tubers or potato yield.

  2. Serotyping and analysis of produced pigments kinds by Pseudomonas aeruginosa clinical isolates

    Directory of Open Access Journals (Sweden)

    Stanković-Nedeljković Nataša

    2011-01-01

    Full Text Available Background/Aim. Pseudomonas aeruginosa (P. aeruginosa is devided into 20 serotypes on the base of the International Antigenic Typing Scheme. P. aeruginosa serotyping is important because of few reasons but epidemiological is the most important. The aim of the study was serotyping of P. aeruginosa clinical isolates, analysing of single clinical isolates P. aeruginosa present in the particular samples, and analysing of pyocianin and fluorescin production in different isolates of P. aeruginosa. Methods. A total of 223 isolates of P. aeruginosa, isolated in the microbiological laboratory of the Health Center “Aleksinac”, Aleksinac, were examinated. P. aeruginosa isolates were put on the pseudomonas isolation agar, pseudomonas agar base, acetamid agar, asparagin prolin broth, pseudomonas asparagin broth, Bushnnell-Haas agar, cetrimid agar base, King A and King B plates, plates for pyocianin production, plates for fluorescin production and tripticasa soya agar (Himedia. Polyvalent and monovalent serums were used in the agglutination (Biorad. Pigment production was analysed on the bases of growth on the plates for pyocianin and fluorescin production. Results. Serologically, we identificated the serovars as follows: O1, O3, O4, O5, O6, O7, O8, O10, O11 and O12. O1 (38% was the most often serovar, then O11 (19% and O6 (8.6%. A total of 18.6% (42 isolates did not agglutinate with any serum, whereas 21 isolates agglutinated only with polyvalent serum. The majority of P. aeruginosa isolates produced fluorescin, 129 (58.54%, 53 (22.94% produced pyocianin whereas 49 (21.21% isolates produced both pigments. Conclusion. P. aeruginosa was isolated most of the from urine, sputum and other materials. The majority often serovars were O1, O6 and O11. The most of isolates produced fluorescin (58.54%, while 22.94% producted pyocianin and 21.21% both pigments.

  3. Pseudomonas aeruginosa septic shock associated with ecthyma gangrenosum in an infant with agammaglobulinemia Choque séptico por Pseudomonas aeruginosa associado a éctima gangrenosa em criança com agamaglobulinemia

    Directory of Open Access Journals (Sweden)

    João Fernando Lourenço de ALMEIDA

    2002-01-01

    Full Text Available Ecthyma gangrenosum (EG due to Pseudomonas aeruginosa is a rare and invasive infection that can be associated with agammaglobulinemia. The cornerstone of the treatment is based on prompt recognition with appropriate antibiotic coverage and intravenous immunoglobulin. The authors report a case of EG emphasizing the clinical and therapeutic aspects of this condition.Éctima Gangrenosa (EG por Pseudomonas aeruginosa é uma infecção rara e invasiva que pode ser associada com agamaglobulinemia. O tratamento fundamental é baseado no pronto reconhecimento com cobertura de antibiótico apropriada e imunoglobulina intravenosa. Os autores relatam caso de EG dando ênfase aos aspectos clínicos e terapêuticos desta condição.

  4. Characterization of corrosive bacterial consortia isolated from petroleum-product-transporting pipelines

    Energy Technology Data Exchange (ETDEWEB)

    Rajasekar, Aruliah; Ting, Yen-Peng [National Univ. of Singapore (Singapore). Dept. of Chemical and Biomolecular Engineering; Anandkumar, Balakrishnan [Sourashtra Coll., Madurai (India). Dept. of Biotechnology; Maruthamuthu, Sundaram [Central Electrochemical Research Inst., Karaikudi (India). Biocorrosion Group; Rahman, Pattanathu K.S.M. [Teesside Univ., Tees Valley (United Kingdom). Chemical and Bioprocess Engineering Group

    2010-01-15

    Microbiologically influenced corrosion is a problem commonly encountered in facilities in the oil and gas industries. The present study describes bacterial enumeration and identification in diesel and naphtha pipelines located in the northwest and southwest region in India, using traditional cultivation technique and 16S rDNA gene sequencing. Phylogenetic analysis of 16S rRNA sequences of the isolates was carried out, and the samples obtained from the diesel and naphtha-transporting pipelines showed the occurrence of 11 bacterial species namely Serratia marcescens ACE2, Bacillus subtilis AR12, Bacillus cereus ACE4, Pseudomonas aeruginosa AI1, Klebsiella oxytoca ACP, Pseudomonas stutzeri AP2, Bacillus litoralis AN1, Bacillus sp., Bacillus pumilus AR2, Bacillus carboniphilus AR3, and Bacillus megaterium AR4. Sulfate-reducing bacteria were not detected in samples from both pipelines. The dominant bacterial species identified in the petroleum pipeline samples were B. cereus and S. marcescens in the diesel and naphtha pipelines, respectively. Therefore, several types of bacteria may be involved in biocorrosion arising from natural biofilms that develop in industrial facilities. In addition, localized (pitting) corrosion of the pipeline steel in the presence of the consortia was observed by scanning electron microscopy analysis. The potential role of each species in biofilm formation and steel corrosion is discussed. (orig.)

  5. Bacterial properties changing under Triton X-100 presence in the diesel oil biodegradation systems: from surface and cellular changes to mono- and dioxygenases activities.

    Science.gov (United States)

    Sałek, Karina; Kaczorek, Ewa; Guzik, Urszula; Zgoła-Grześkowiak, Agnieszka

    2015-03-01

    Triton X-100, as one of the most popular surfactants used in bioremediation techniques, has been reported as an effective agent enhancing the biodegradation of hydrocarbons. However efficient, the surfactant's role in different processes that together enable the satisfying biodegradation should be thoroughly analysed and verified. In this research, we present the interactions of Triton X-100 with the bacterial surfaces (hydrophobicity and zeta potential), its influence on the enzymatic properties (considering mono- and dioxygenases) and profiles of fatty acids, which then all together were compared with the biodegradation rates. The addition of various concentrations of Triton X-100 to diesel oil system revealed different cell surface hydrophobicity (CSH) of the tested strains. The results demonstrated that for Pseudomonas stutzeri strain 9, higher diesel oil biodegradation was correlated with hydrophilic properties of the tested strain and lower Triton X-100 biodegradation. Furthermore, an increase of the branched fatty acids was observed for this strain.

  6. Comparison of Neutrophil Apoptosis by the Pseudomonas Aeruginosa Exotoxins between Healthy Individuals and Term Infants

    Directory of Open Access Journals (Sweden)

    Soheila Khazaei

    2013-04-01

    Full Text Available Background: Pseudomonas aeruginosa may be colonized in different human tissues and result in some infections potentially. Thus, considering that these bacteria are resistance to most of the current antibiotics, an examination on pathogenesis mechanisms of such bacteria can be effective in controlling the infections developed by it.Materials and Methods: In this project, among 40 blood samples (20 healthy persons, 20 infants, an amount of 5 ml (2 ml in the infants heparinized blood was collected form each and then neutrophils were isolated by a standard method and were counted by neubauer lam. After culturing Pseudomonas bacteria in broth medium, some tubes with densities of 1, 2, 3 and 4 McFarland were prepared and the bacteria were isolated by centrifuge method with 3000rpm for 10 minutes and then its exotoxin were exposed to neutrophils of the groups under study. The effect of time and the bacteria count on the amount of the secreted toxin and in adjacency to neutrophils was measured.Results: There were 11 men and 9 women in the health group and the infants group consisted of 12 boys and 8 girls. Death cell percentage of neutrophils was 100% in the health group and 8.90% in the infants group. Percentage of bacterial growth in the medium 1 and 2 McFarland was zero; in the medium 3 McFarland, it was 12.5% in the healthy group and 1% in the infants group (p<0.10. The average rate of cell death in the minute 15th was different in two groups (68.5% in health group vs. 92.5% in the infants (p<0.0005. Conclusion: This study showed the effect of Pseudomonas bacteria on the development of early cell death in the infants very well. As it was shown, this effect is time-dependent and this cell death (apoptosis is occurred in the infants earlier than health people.

  7. Antimicrobial properties of Pseudomonas strains producing the antibiotic mupirocin.

    Science.gov (United States)

    Matthijs, Sandra; Vander Wauven, Corinne; Cornu, Bertrand; Ye, Lumeng; Cornelis, Pierre; Thomas, Christopher M; Ongena, Marc

    2014-10-01

    Mupirocin is a polyketide antibiotic with broad antibacterial activity. It was isolated and characterized about 40 years ago from Pseudomonas fluorescens NCIMB 10586. To study the phylogenetic distribution of mupirocin producing strains in the genus Pseudomonas a large collection of Pseudomonas strains of worldwide origin, consisting of 117 Pseudomonas type strains and 461 strains isolated from different biological origins, was screened by PCR for the mmpD gene of the mupirocin gene cluster. Five mmpD(+) strains from different geographic and biological origin were identified. They all produced mupirocin and were strongly antagonistic against Staphylococcus aureus. Phylogenetic analysis showed that mupirocin production is limited to a single species. Inactivation of mupirocin production leads to complete loss of in vitro antagonism against S. aureus, except on certain iron-reduced media where the siderophore pyoverdine is responsible for the in vitro antagonism of a mupirocin-negative mutant. In addition to mupirocin some of the strains produced lipopeptides of the massetolide group. These lipopeptides do not play a role in the observed in vitro antagonism of the mupirocin producing strains against S. aureus. Copyright © 2014 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

  8. Gentamicin in Pseudomonas aeruginosa

    African Journals Online (AJOL)

    infections by Ps. aeruginosa is contra-indicated. In our study only 2,3 % of the Ps. aeruginosa strains were resistant to gentamicin (MIC 25 Ilg/ml). In view of the synergy reported for combined gentamicin and carbeni- cillin therapy," a combination of these two drugs may be recommended in the treatment of all Pseudomonas.

  9. Peptidoglycan transpeptidase inhibition in Pseudomonas aeruginosa and Escherichia coli by Penicillins and Cephalosporins.

    Science.gov (United States)

    Moore, B A; Jevons, S; Brammer, K W

    1979-04-01

    Peptidoglycan transpeptidase activity has been studied in cells of Escherichia coli 146 and Pseudomonas aeruginosa 56 made permeable to exogenous, nucleotide-sugar peptidoglycan precursors by ether treatment. Transpeptidase activity was inhibited, in both organisms, by a range of penicillins and cephalosporins, the Pseudomonas enzyme being more sensitive to inhibition in each case. Conversely, growth of E. coli 146 was more susceptible to these antibiotics than growth of P. aeruginosa 56. Furthermore, similar transpeptidase inhibition values were ob-obtained for the four penicillins examined against the Pseudomonas enzyme, although only two of these (carbenicillin and pirbenicillin) inhibited the growth of this organism. We therefore conclude that the high resistance of P. aeruginosa 56 to growth inhibition by most beta-lactam antibiotics cannot be due to an insensitive peptidoglycan transpeptidase.

  10. A decade of crystallization drops: crystallization of the cbb3 cytochrome c oxidase from Pseudomonas stutzeri.

    Science.gov (United States)

    Buschmann, Sabine; Richers, Sebastian; Ermler, Ulrich; Michel, Hartmut

    2014-04-01

    The cbb3 cytochrome c oxidases are distant members of the superfamily of heme copper oxidases. These terminal oxidases couple O2 reduction with proton transport across the plasma membrane and, as a part of the respiratory chain, contribute to the generation of an electrochemical proton gradient. Compared with other structurally characterized members of the heme copper oxidases, the recently determined cbb3 oxidase structure at 3.2 Å resolution revealed significant differences in the electron supply system, the proton conducting pathways and the coupling of O2 reduction to proton translocation. In this paper, we present a detailed report on the key steps for structure determination. Improvement of the protein quality was achieved by optimization of the number of lipids attached to the protein as well as the separation of two cbb3 oxidase isoenzymes. The exchange of n-dodecyl-β-D-maltoside for a precisely defined mixture of two α-maltosides and decanoylsucrose as well as the choice of the crystallization method had a most profound impact on crystal quality. This report highlights problems frequently encountered in membrane protein crystallization and offers meaningful approaches to improve crystal quality. © 2014 The Protein Society.

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

    Science.gov (United States)

    Nwinyi, Obinna C; Ajayi, Oluseyi O; Amund, Olukayode O

    2016-01-01

    The goal of this investigation was to isolate competent polynuclear aromatic hydrocarbons degraders that can utilize polynuclear aromatic hydrocarbons of former industrial sites at McDoel Switchyard in Bloomington, Indiana. Using conventional enrichment method based on soil slurry, we isolated, screened and purified two bacterial species strains PB1 and PB2. Applying the ribotyping technique using the 16S rRNA gene analysis, the strains were assigned to the genus Pseudomonas (Pseudomonas plecoglossicida strain PB1 and Pseudomonas sp. PB2). Both isolates showed promising metabolic capacity on pyrene sprayed MS agar plates during the preliminary investigations. Using time course studies in the liquid cultures at calculated concentrations 123, 64, 97 and 94ppm for naphthalene, chrysene, fluroanthene and pyrene, P. plecoglossicida strain PB1 and Pseudomonas sp. PB2 showed partial utilization of the polynuclear aromatic hydrocarbons. Naphthalene was degraded between 26% and 40%, chrysene 14% and 16%, fluroanthene 5% and 7%; pyrene 8% and 13% by P. plecoglossicida strain PB1 and Pseudomonas sp. PB2 respectively. Based on their growth profile, we developed a model R(2)=1 to predict the degradation rate of slow polynuclear aromatic hydrocarbon-degraders where all the necessary parameters are constant. From this investigation, we confirm that the former industrial site soil microbial communities may be explored for the biorestoration of the industrial site. Copyright © 2016. Published by Elsevier Editora Ltda.

  12. [The effect of biyuanshu oral liquid on the formation of Pseudomonas aeruginosa biofilms in vitro].

    Science.gov (United States)

    Liu, Xiang; Chen, Haihong; Wang, Shengqing

    2012-07-01

    To observe the effect of biyuanshu oral liquid on the formation of pseudomonas aeruginosa biofilms in vitro. Pseudomonas aeruginosa biofilm was established by plate culture and detected by Scanning electron microscopy and AgNO3 staining. After treated with different dosages of biyuanshu oral liquid and erythromycin, the pseudomonas aeruginosa biofilms were observed by AgNO3 staining and the number of viable bacteria were measured by serial dilution. The pseudomonas aeruginosa biofilms could be detected by SEM at the seventh culture day and it was consistent with the detection of AgNO3 staining. The biyuanshu oral liquid and erythromycin have the effect on inhibiting the formation of pseudomonas aeruginosa biofilms. But with the already formed pseudomonas aeruginosa biofilms the inhibition was not significant. The serial dilution method showed that the viable counts of bacteria of biyuanshu oral liquid and erythromycin treated groups were significantly lower than those untreated groups (P formation of pseudomonas aeruginosa biofilms in vitro.

  13. Pesquisa de Acinetobacter sp e Pseudomonas aeruginosa produtores de metalo-β-lactamase em hospital de emergência de Porto Alegre, Estado do Rio Grande do Sul, Brasil Investigation of metallo-β-lactamase-producing Acinetobacter sp and Pseudomonas aeruginosa at an emergency hospital in Porto Alegre, State of Rio Grande do Sul, Brazil

    Directory of Open Access Journals (Sweden)

    Vani Dos Santos Laranjeira

    2010-08-01

    Full Text Available INTRODUÇÃO: O aparecimento de Pseudomonas aeruginosa e Acinetobacter sp produtores de metalo-β-lactamases (MBLs é um desafio para os hospitais. MÉTODOS: Verificou-se a produção de MBL em cepas clínicas de Pseudomonas aeruginosa e Acinetobacter sp de um hospital de emergência de Porto Alegre pelo método de aproximação de disco e E-test MBL. Os genes bla foram pesquisados pela PCR. RESULTADOS: Duas cepas de Pseudomonas aeruginosa e oito Acinetobacter sp demonstraram fenótipo de MBLs. A amplificação do gene blaSPM-1 confirmou a enzima em P. aeruginosa.. CONCLUSÕES: Deve-se ter cautela ao avaliar testes fenotípicos utilizados na detecção rotineira de metalo-enzima.INTRODUCTION: The appearance of metallo-β-lactamase (MBL-producing Pseudomonas aeruginosa and Acinetobacter sp. is a challenge for hospitals. METHODS: The production of MBL in clinical isolates of Pseudomonas aeruginosa and Acinetobacter sp. From an emergency hospital in Porto Alegre was investigated using the disk approximation test and MBL E-test. The bla genes were determined using PCR. RESULTS: Two strains of Pseudomonas aeruginosa and eight of Acinetobacter sp were shown to be MBL phenotypes. Amplification of the blaSPM-1 gene confirmed the presence of the enzyme in P. aeruginosa. CONCLUSIONS: Caution is needed in evaluating phenotype tests used for routine detection of metallo-β-lactamases.

  14. Production and characterization of biosurfactant produced by a novel Pseudomonas sp. 2B.

    Science.gov (United States)

    Aparna, A; Srinikethan, G; Smitha, H

    2012-06-15

    Biosurfactant-producing bacteria were isolated from terrestrial samples collected in areas contaminated with petroleum compounds. Isolates were screened for biosurfactant production using Cetyl Tri Ammonium Bromide (CTAB)-Methylene blue agar selection medium and the qualitative drop-collapse test. An efficient bacterial strain was selected based on rapid drop collapse activity and highest biosurfactant production. The biochemical characteristics and partial sequenced 16S rRNA gene of isolate, 2B, identified the bacterium as Pseudomonas sp. Five different low cost carbon substrates were evaluated for their effect on biosurfactant production. The maximum biosurfactant synthesis (4.97 g/L) occurred at 96 h when the cells were grown on modified PPGAS medium containing 1% (v/v) molasses at 30 °C and 150 rpm. The cell free broth containing the biosurfactant could reduce the surface tension to 30.14 mN/m. The surface active compound showed emulsifying activity against a variety of hydrocarbons and achieved a maximum emulsion index of 84% for sunflower oil. Compositional analysis of the biosurfactant reveals that the extracted biosurfactant was a glycolipid type, which was composed of high percentages of lipid (∼65%, w/w) and carbohydrate (∼32%, w/w). Fourier transform infrared (FT-IR) spectrum of extracted biosurfactant indicates the presence of carboxyl, hydroxyl and methoxyl functional groups. The mass spectra (MS) shows that dirhamnolipid (l-rhamnopyranosyl-l-rhamnopyranosyl-3-hydroxydecanoyl-3-hydroxydecanoate, Rha-Rha-C(10)-C(10)) was detected in abundance with the predominant congener monorhamnolipid (l-rhamnopyranosyl-β-hydroxydecanoyl-β-hydroxydecanoate, Rha-C(10)-C(10)). The crude oil recovery studies using the biosurfactant produced by Pseudomonas sp. 2B suggested its potential application in microbial enhanced oil recovery and bioremediation. Copyright © 2012 Elsevier B.V. All rights reserved.

  15. Rhizosphere-associated Pseudomonas induce systemic resistance to herbivores at the cost of susceptibility to bacterial pathogens.

    Science.gov (United States)

    Haney, Cara H; Wiesmann, Christina L; Shapiro, Lori R; Melnyk, Ryan A; O'Sullivan, Lucy R; Khorasani, Sophie; Xiao, Li; Han, Jiatong; Bush, Jenifer; Carrillo, Juli; Pierce, Naomi E; Ausubel, Frederick M

    2017-10-31

    Plant-associated soil microbes are important mediators of plant defence responses to diverse above-ground pathogen and insect challengers. For example, closely related strains of beneficial rhizosphere Pseudomonas spp. can induce systemic resistance (ISR), systemic susceptibility (ISS) or neither against the bacterial foliar pathogen Pseudomonas syringae pv. tomato DC3000 (Pto DC3000). Using a model system composed of root-associated Pseudomonas spp. strains, the foliar pathogen Pto DC3000 and the herbivore Trichoplusia ni (cabbage looper), we found that rhizosphere-associated Pseudomonas spp. that induce either ISS and ISR against Pto DC3000 all increased resistance to herbivory by T. ni. We found that resistance to T. ni and resistance to Pto DC3000 are quantitative metrics of the jasmonic acid (JA)/salicylic acid (SA) trade-off and distinct strains of rhizosphere-associated Pseudomonas spp. have distinct effects on the JA/SA trade-off. Using genetic analysis and transcriptional profiling, we provide evidence that treatment of Arabidopsis with Pseudomonas sp. CH267, which induces ISS against bacterial pathogens, tips the JA/SA trade-off towards JA-dependent defences against herbivores at the cost of a subset of SA-mediated defences against bacterial pathogens. In contrast, treatment of Arabidopsis with the ISR strain Pseudomonas sp. WCS417 disrupts JA/SA antagonism and simultaneously primes plants for both JA- and SA-mediated defences. Our findings show that ISS against the bacterial foliar pathogens triggered by Pseudomonas sp. CH267, which is a seemingly deleterious phenotype, may in fact be an adaptive consequence of increased resistance to herbivory. Our work shows that pleiotropic effects of microbiome modulation of plant defences are important to consider when using microbes to modify plant traits in agriculture. © 2017 John Wiley & Sons Ltd.

  16. Draft Genome Sequence Analysis of a Pseudomonas putida W15Oct28 Strain with Antagonistic Activity to Gram-Positive and Pseudomonas sp. Pathogens

    Science.gov (United States)

    Ye, Lumeng; Hildebrand, Falk; Dingemans, Jozef; Ballet, Steven; Laus, George; Matthijs, Sandra; Berendsen, Roeland; Cornelis, Pierre

    2014-01-01

    Pseudomonas putida is a member of the fluorescent pseudomonads known to produce the yellow-green fluorescent pyoverdine siderophore. P. putida W15Oct28, isolated from a stream in Brussels, was found to produce compound(s) with antimicrobial activity against the opportunistic pathogens Staphylococcus aureus, Pseudomonas aeruginosa, and the plant pathogen Pseudomonas syringae, an unusual characteristic for P. putida. The active compound production only occurred in media with low iron content and without organic nitrogen sources. Transposon mutants which lost their antimicrobial activity had the majority of insertions in genes involved in the biosynthesis of pyoverdine, although purified pyoverdine was not responsible for the antagonism. Separation of compounds present in culture supernatants revealed the presence of two fractions containing highly hydrophobic molecules active against P. aeruginosa. Analysis of the draft genome confirmed the presence of putisolvin biosynthesis genes and the corresponding lipopeptides were found to contribute to the antimicrobial activity. One cluster of ten genes was detected, comprising a NAD-dependent epimerase, an acetylornithine aminotransferase, an acyl CoA dehydrogenase, a short chain dehydrogenase, a fatty acid desaturase and three genes for a RND efflux pump. P. putida W15Oct28 genome also contains 56 genes encoding TonB-dependent receptors, conferring a high capacity to utilize pyoverdines from other pseudomonads. One unique feature of W15Oct28 is also the presence of different secretion systems including a full set of genes for type IV secretion, and several genes for type VI secretion and their VgrG effectors. PMID:25369289

  17. Streptococcus pneumoniae and Pseudomonas aeruginosa pneumonia induce distinct host responses.

    Science.gov (United States)

    McConnell, Kevin W; McDunn, Jonathan E; Clark, Andrew T; Dunne, W Michael; Dixon, David J; Turnbull, Isaiah R; Dipasco, Peter J; Osberghaus, William F; Sherman, Benjamin; Martin, James R; Walter, Michael J; Cobb, J Perren; Buchman, Timothy G; Hotchkiss, Richard S; Coopersmith, Craig M

    2010-01-01

    Pathogens that cause pneumonia may be treated in a targeted fashion by antibiotics, but if this therapy fails, then treatment involves only nonspecific supportive measures, independent of the inciting infection. The purpose of this study was to determine whether host response is similar after disparate infections with similar mortalities. Prospective, randomized controlled study. Animal laboratory in a university medical center. Pneumonia was induced in FVB/N mice by either Streptococcus pneumoniae or two different concentrations of Pseudomonas aeruginosa. Plasma and bronchoalveolar lavage fluid from septic animals was assayed by a microarray immunoassay measuring 18 inflammatory mediators at multiple time points. The host response was dependent on the causative organism as well as kinetics of mortality, but the pro-inflammatory and anti-inflammatory responses were independent of inoculum concentration or degree of bacteremia. Pneumonia caused by different concentrations of the same bacteria, Pseudomonas aeruginosa, also yielded distinct inflammatory responses; however, inflammatory mediator expression did not directly track the severity of infection. For all infections, the host response was compartmentalized, with markedly different concentrations of inflammatory mediators in the systemic circulation and the lungs. Hierarchical clustering analysis resulted in the identification of five distinct clusters of the host response to bacterial infection. Principal components analysis correlated pulmonary macrophage inflammatory peptide-2 and interleukin-10 with progression of infection, whereas elevated plasma tumor necrosis factor sr2 and macrophage chemotactic peptide-1 were indicative of fulminant disease with >90% mortality within 48 hrs. Septic mice have distinct local and systemic responses to Streptococcus pneumoniae and Pseudomonas aeruginosa pneumonia. Targeting specific host inflammatory responses induced by distinct bacterial infections could represent a

  18. A lung segmental model of chronic Pseudomonas infection in sheep.

    Directory of Open Access Journals (Sweden)

    David Collie

    Full Text Available Chronic lung infection with Pseudomonas aeruginosa is a major contributor to morbidity, mortality and premature death in cystic fibrosis. A new paradigm for managing such infections is needed, as are relevant and translatable animal models to identify and test concepts. We sought to improve on limitations associated with existing models of infection in small animals through developing a lung segmental model of chronic Pseudomonas infection in sheep.Using local lung instillation of P. aeruginosa suspended in agar beads we were able to demonstrate that such infection led to the development of a suppurative, necrotising and pyogranulomatous pneumonia centred on the instilled beads. No overt evidence of organ or systemic compromise was apparent in any animal during the course of infection. Infection persisted in the lungs of individual animals for as long as 66 days after initial instillation. Quantitative microbiology applied to bronchoalveolar lavage fluid derived from infected segments proved an insensitive index of the presence of significant infection in lung tissue (>10(4 cfu/g.The agar bead model of chronic P. aeruginosa lung infection in sheep is a relevant platform to investigate both the pathobiology of such infections as well as novel approaches to their diagnosis and therapy. Particular ethical benefits relate to the model in terms of refining existing approaches by compromising a smaller proportion of the lung with infection and facilitating longitudinal assessment by bronchoscopy, and also potentially reducing animal numbers through facilitating within-animal comparisons of differential therapeutic approaches.

  19. A lung segmental model of chronic Pseudomonas infection in sheep.

    Science.gov (United States)

    Collie, David; Govan, John; Wright, Steven; Thornton, Elisabeth; Tennant, Peter; Smith, Sionagh; Doherty, Catherine; McLachlan, Gerry

    2013-01-01

    Chronic lung infection with Pseudomonas aeruginosa is a major contributor to morbidity, mortality and premature death in cystic fibrosis. A new paradigm for managing such infections is needed, as are relevant and translatable animal models to identify and test concepts. We sought to improve on limitations associated with existing models of infection in small animals through developing a lung segmental model of chronic Pseudomonas infection in sheep. Using local lung instillation of P. aeruginosa suspended in agar beads we were able to demonstrate that such infection led to the development of a suppurative, necrotising and pyogranulomatous pneumonia centred on the instilled beads. No overt evidence of organ or systemic compromise was apparent in any animal during the course of infection. Infection persisted in the lungs of individual animals for as long as 66 days after initial instillation. Quantitative microbiology applied to bronchoalveolar lavage fluid derived from infected segments proved an insensitive index of the presence of significant infection in lung tissue (>10(4) cfu/g). The agar bead model of chronic P. aeruginosa lung infection in sheep is a relevant platform to investigate both the pathobiology of such infections as well as novel approaches to their diagnosis and therapy. Particular ethical benefits relate to the model in terms of refining existing approaches by compromising a smaller proportion of the lung with infection and facilitating longitudinal assessment by bronchoscopy, and also potentially reducing animal numbers through facilitating within-animal comparisons of differential therapeutic approaches.

  20. Bacteriophage Infectivity Against Pseudomonas aeruginosa in Saline Conditions

    KAUST Repository

    Scarascia, Giantommaso

    2018-05-02

    Pseudomonas aeruginosa is a ubiquitous member of marine biofilm, and reduces thiosulfate to produce toxic hydrogen sulfide gas. In this study, lytic bacteriophages were isolated and applied to inhibit the growth of P. aeruginosa in planktonic mode at different temperature, pH, and salinity. Bacteriophages showed optimal infectivity at a multiplicity of infection of 10 in saline conditions, and demonstrated lytic abilities over all tested temperature (25, 30, 37, and 45°C) and pH 6–9. Planktonic P. aeruginosa exhibited significantly longer lag phase and lower specific growth rates upon exposure to bacteriophages. Bacteriophages were subsequently applied to P. aeruginosa-enriched biofilm and were determined to lower the relative abundance of Pseudomonas-related taxa from 0.17 to 5.58% in controls to 0.01–0.61% in treated microbial communities. The relative abundance of Alphaproteobacteria, Pseudoalteromonas, and Planococcaceae decreased, possibly due to the phage-induced disruption of the biofilm matrix. Lastly, when applied to mitigate biofouling of ultrafiltration membranes, bacteriophages were determined to reduce the transmembrane pressure increase by 18% when utilized alone, and by 49% when used in combination with citric acid. The combined treatment was more effective compared with the citric acid treatment alone, which reported ca. 30% transmembrane pressure reduction. Collectively, the findings demonstrated that bacteriophages can be used as a biocidal agent to mitigate undesirable P. aeruginosa-associated problems in seawater applications.

  1. Choosing an Appropriate Infection Model to Study Quorum Sensing Inhibition in Pseudomonas Infections

    Directory of Open Access Journals (Sweden)

    Evelina Papaioannou

    2013-09-01

    Full Text Available Bacteria, although considered for decades to be antisocial organisms whose sole purpose is to find nutrients and multiply are, in fact, highly communicative organisms. Referred to as quorum sensing, cell-to-cell communication mechanisms have been adopted by bacteria in order to co-ordinate their gene expression. By behaving as a community rather than as individuals, bacteria can simultaneously switch on their virulence factor production and establish successful infections in eukaryotes. Understanding pathogen-host interactions requires the use of infection models. As the use of rodents is limited, for ethical considerations and the high costs associated with their use, alternative models based on invertebrates have been developed. Invertebrate models have the benefits of low handling costs, limited space requirements and rapid generation of results. This review presents examples of such models available for studying the pathogenicity of the Gram-negative bacterium Pseudomonas aeruginosa. Quorum sensing interference, known as quorum quenching, suggests a promising disease-control strategy since quorum-quenching mechanisms appear to play important roles in microbe-microbe and host-pathogen interactions. Examples of natural and synthetic quorum sensing inhibitors and their potential as antimicrobials in Pseudomonas-related infections are discussed in the second part of this review.

  2. Diversity of Pseudomonas Genomes, Including Populus-Associated Isolates, as Revealed by Comparative Genome Analysis.

    Science.gov (United States)

    Jun, Se-Ran; Wassenaar, Trudy M; Nookaew, Intawat; Hauser, Loren; Wanchai, Visanu; Land, Miriam; Timm, Collin M; Lu, Tse-Yuan S; Schadt, Christopher W; Doktycz, Mitchel J; Pelletier, Dale A; Ussery, David W

    2016-01-01

    The Pseudomonas genus contains a metabolically versatile group of organisms that are known to occupy numerous ecological niches, including the rhizosphere and endosphere of many plants. Their diversity influences the phylogenetic diversity and heterogeneity of these communities. On the basis of average amino acid identity, comparative genome analysis of >1,000 Pseudomonas genomes, including 21 Pseudomonas strains isolated from the roots of native Populus deltoides (eastern cottonwood) trees resulted in consistent and robust genomic clusters with phylogenetic homogeneity. All Pseudomonas aeruginosa genomes clustered together, and these were clearly distinct from other Pseudomonas species groups on the basis of pangenome and core genome analyses. In contrast, the genomes of Pseudomonas fluorescens were organized into 20 distinct genomic clusters, representing enormous diversity and heterogeneity. Most of our 21 Populus-associated isolates formed three distinct subgroups within the major P. fluorescens group, supported by pathway profile analysis, while two isolates were more closely related to Pseudomonas chlororaphis and Pseudomonas putida. Genes specific to Populus-associated subgroups were identified. Genes specific to subgroup 1 include several sensory systems that act in two-component signal transduction, a TonB-dependent receptor, and a phosphorelay sensor. Genes specific to subgroup 2 contain hypothetical genes, and genes specific to subgroup 3 were annotated with hydrolase activity. This study justifies the need to sequence multiple isolates, especially from P. fluorescens, which displays the most genetic variation, in order to study functional capabilities from a pangenomic perspective. This information will prove useful when choosing Pseudomonas strains for use to promote growth and increase disease resistance in plants. Copyright © 2015 Jun et al.

  3. Pseudomonas biofilm matrix composition and niche biology

    Science.gov (United States)

    Mann, Ethan E.; Wozniak, Daniel J.

    2014-01-01

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

  4. Mecanismos de Adherencia de Pseudomonas aeruginosa a nuevos Biomateriales de uso Médico.

    OpenAIRE

    Martínez Martínez, Luis

    2017-01-01

    En 1882 Gessard aisló por primera vez Pseudomonas aeruginosa (Bacillus pyoceaneus) de muestras procedentes de heridas quirúrgicas. Hasta 1947 sólo se conocían 91 casos de bacteriemia por este microorganismo, pero en la década actual, cien años después de su descripción, Pseudomonas aeruginosa, ha pasado a ser un microorganismo de creciente interés en patología humana debido a su estrecha relación con enfermos inmun...

  5. Short communication: Pseudomonas azotoformans causes gray discoloration in HTST fluid milk.

    Science.gov (United States)

    Evanowski, Rachel L; Reichler, Samuel J; Kent, David J; Martin, Nicole H; Boor, Kathryn J; Wiedmann, Martin

    2017-10-01

    Pseudomonas species are well recognized as dairy product spoilage organisms, particularly due to their ability to grow at refrigeration temperatures. Although Pseudomonas-related spoilage usually manifests itself in flavor, odor, and texture defects, which are typically due to production of bacterial enzymes, Pseudomonas is also reported to cause color defects. Because of consumer complaints, a commercial dairy company shipped 4 samples of high temperature, short time (HTST)-pasteurized milk with distinctly gray colors to our laboratory. Bacterial isolates from all 4 samples were identified as Pseudomonas azotoformans. All isolates shared the same partial 16S rDNA sequence and showed black pigmentation on Dichloran Rose Bengal Chloramphenicol agar. Inoculation of one pigment-producing P. azotoformans isolate into HTST-pasteurized fluid milk led to development of gray milk after 14 d of storage at 6°C, but only in containers that had half of the total volume filled with milk (∼500 mL of milk in ∼1,000-mL bottles). We conclusively demonstrate that Pseudomonas can cause a color defect in fluid milk that manifests in gray discoloration, adding to the palette of color defects known to be caused by Pseudomonas. This information is of considerable interest to the dairy industry, because dairy processors and others may not typically associate black or gray colors in fluid milk with the presence of microbial contaminants but rather with product tampering (e.g., addition of ink) or other inadvertent chemical contamination. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  6. Enzyme-mediated quenching of the Pseudomonas quinolone signal (PQS promotes biofilm formation of Pseudomonas aeruginosa by increasing iron availability

    Directory of Open Access Journals (Sweden)

    Beatrix Tettmann

    2016-12-01

    Full Text Available The 2-alkyl-3-hydroxy-4(1H-quinolone 2,4-dioxygenase HodC was previously described to cleave the Pseudomonas quinolone signal, PQS, which is exclusively used in the complex quorum sensing (QS system of Pseudomonas aeruginosa, an opportunistic pathogen employing QS to regulate virulence and biofilm development. Degradation of PQS by exogenous addition of HodC to planktonic cells of P. aeruginosa attenuated production of virulence factors, and reduced virulence in planta. However, proteolytic cleavage reduced the efficacy of HodC. Here, we identified the secreted protease LasB of P. aeruginosa to be responsible for HodC degradation. In static biofilms of the P. aeruginosa PA14 lasB::Tn mutant, the catalytic activity of HodC led to an increase in viable biomass in newly formed but also in established biofilms, and reduced the expression of genes involved in iron metabolism and siderophore production, such as pvdS, pvdL, pvdA and pvdQ. This is likely due to an increase in the levels of bioavailable iron by degradation of PQS, which is able to sequester iron from the surrounding environment. Thus, HodC, despite its ability to quench the production of virulence factors, is contraindicated for combating P. aeruginosa biofilms.

  7. Facial Nerve Paralysis seen in Pseudomonas sepsis with ecthyma gangrenosum

    Directory of Open Access Journals (Sweden)

    Suleyman Ozdemir

    2013-02-01

    Full Text Available Ecthyma gangrenosum is a skin lesion which is created by pseudomonas auriginosa. Peripheral facial paralysis and mastoiditis as a rare complication of otitis media induced by pseudomonas auriginosa.In this study, 4 months child who has ecthyma gangrenosum and facial nerve paralysis was reported. [Cukurova Med J 2013; 38(1.000: 126-130

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

    NARCIS (Netherlands)

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

    2001-01-01

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

  9. 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.

  10. 40 CFR 180.1107 - Delta endotoxin of Bacillus thuringiensis variety kurstaki encapsulated into killed Pseudomonas...

    Science.gov (United States)

    2010-07-01

    ... thuringiensis variety kurstaki encapsulated into killed Pseudomonas fluorescens; exemption from the requirement... killed Pseudomonas fluorescens; exemption from the requirement of a tolerance. The delta endotoxin of Bacillus thuringiensis variety kurstaki encapsulated into killed Pseudomonas fluorescens is exempt from the...

  11. Detectie en beheersing van bacterierot veroorzaakt door Pseudomonas cattleyae in Phalaenopsis

    NARCIS (Netherlands)

    Ludeking, D.J.W.; Hamelink, R.; Kromwijk, J.A.M.; Schenk, M.F.; Vermunt, A.; Woets, F.

    2011-01-01

    Phalaenopsis growers suffer from mayor losses up to 20% due to bacterial spot. This bacterial infection in caused by the Acidovorax avenae subsp. cattleyae. In practice this bacterial disease is also known as Pseudomonas. This bacterium is causing black leaf spots with a yellow border. Pseudomonas

  12. Glyphosate catabolism by Pseudomonas sp

    International Nuclear Information System (INIS)

    Shinabarger, D.L.

    1986-01-01

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

  13. Foam separation of Pseudomonas fluorescens and Bacillus subtilis var. niger.

    Science.gov (United States)

    Grieves, R B; Wang, S L

    1967-01-01

    An experimental investigation established the effect of the presence of inorganic salts on the foam separation of Pseudomonas fluorescens and of Bacillus subtilis var. niger (B. globigii) from aqueous suspension by use of a cationic surfactant. For P. fluorescens, 5.0 mueq/ml of NaCl, KCl, Na(2)SO(4), K(2)SO(4), CaCl(2), CaSO(4), MgCl(2), or MgSO(4) produced increases in the cell concentration in the residual suspension (not carried into the foam) from 2.9 x 10(5) up to 1.6 x 10(6) to 2.8 x 10(7) cells per milliliter (initial suspensions contain from 3.3 x 10(7) to 4.8 x 10(7) cells per milliliter). The exceptional influence of magnesium was overcome by bringing the cells into contact first with the surfactant and then the salt. For B. subtilis, the presence of 5.0 mueq/ml of any of the eight salts increased the residual cell concentration by one order of magnitude from 1.2 x 10(4) to about 4.0 x 10(5) cells per milliliter. This occurred regardless of the sequence of contact as long as the surfactant contact period was sufficient. The presence of salts increased collapsed foam volumes with P. fluorescens and decreased collapsed foam volumes with B. subtilis.

  14. Comparative In Vitro Efficacy of Doripenem and Imipenem Against Multi-Drug Resistant Pseudomonas aeruginosa.

    Science.gov (United States)

    Wali, Nadia; Mirza, Irfan Ali

    2016-04-01

    To compare the in vitro efficacy of doripenem and imipenem against multi-drug resistant (MDR) Pseudomonas aeruginosa from various clinical specimens. Descriptive cross-sectional study. Department of Microbiology, Armed Forces Institute of Pathology, Rawalpindi, from November 2012 to November 2013. MDR Pseudomonas aeruginosa isolates from various clinical samples were included in the study. Susceptibility of Pseudomonas aeruginosa against doripenem and imipenem was performed by E-test strip and agar dilution methods. The results were interpreted as recommended by Clinical Laboratory Standard Institute (CLSI) guidelines. The maximum number of Pseudomonas aeruginosa were isolated from pure pus and pus swabs. In vitro efficacy of doripenem was found to be more effective as compared to imipenem against MDR Pseudomonas aeruginosa with both E-test strip and agar dilution methods. Overall, p-values of 0.014 and 0.037 were observed when susceptibility patterns of doripenem and imipenem were evaluated with E-test strip and agar dilution methods. In vitro efficacy of doripenem was found to be better against MDR Pseudomonas aeruginosaas compared to imipenem when tested by both E-test and agar dilution methods.

  15. Molecular Cloning and Functional Expression of a Δ9- Fatty Acid Desaturase from an Antarctic Pseudomonas sp. A3

    Science.gov (United States)

    Garba, Lawal; Mohamad Ali, Mohd Shukuri; Oslan, Siti Nurbaya; Rahman, Raja Noor Zaliha Raja Abd

    2016-01-01

    Fatty acid desaturase enzymes play an essential role in the synthesis of unsaturated fatty acids. Pseudomonas sp. A3 was found to produce a large amount of palmitoleic and oleic acids after incubation at low temperatures. Using polymerase Chain Reaction (PCR), a novel Δ9- fatty acid desaturase gene was isolated, cloned, and successfully expressed in Escherichia coli. The gene was designated as PA3FAD9 and has an open reading frame of 1,185 bp which codes for 394 amino acids with a predicted molecular weight of 45 kDa. The activity of the gene product was confirmed via GCMS, which showed a functional putative Δ9-fatty acid desaturase capable of increasing the total amount of cellular unsaturated fatty acids of the E. coli cells expressing the gene. The results demonstrate that the cellular palmitoleic acids have increased two-fold upon expression at 15°C using only 0.1 mM IPTG. Therefore, PA3FAD9 from Pseudomonas sp.A3 codes for a Δ9-fatty acid desaturase-like protein which was actively expressed in E. coli. PMID:27494717

  16. Production of Polyhydroxyalkanoates from Sludge Palm Oil Using Pseudomonas putida S12.

    Science.gov (United States)

    Kang, Du-Kyeong; Lee, Cho-Ryong; Lee, Sun Hee; Bae, Jung-Hoon; Park, Young-Kwon; Rhee, Young Ha; Sung, Bong Hyun; Sohn, Jung-Hoon

    2017-05-28

    Polyhydroxyalkanoates (PHAs) are biodegradable plastics produced by bacteria, but their use in diverse applications is prohibited by high production costs. To reduce these costs, the conversion by Pseudomonas strains of P HAs from crude s ludge p alm oil ( SPO) a s an inexpensive renewable raw material was tested. Pseudomonas putida S12 was found to produce the highest yield (~41%) of elastomeric medium-chain-length (MCL)-PHAs from SPO. The MCL-PHA characteristics were analyzed by gas-chromatography/mass spectrometry, gel permeation chromatography, and differential scanning calorimetry. These findings may contribute to more widespread use of PHAs by reducing PHA production costs.

  17. In situ detection of denitrifying bacteria by mRNA-targeted nucleic acid probes and catalyzed reporter deposition

    DEFF Research Database (Denmark)

    Kofoed, Michael Vedel; Stief, Peter; Poulsen, Morten

    can be designed to target a broader range of denitrifying bacteria; however, they require two-pass CARD-FISH, which may result in (too) high background fluorescence. In a first application example, habitat-specific polynucleotide probes were used to quantify bacteria expressing narG and nos...... reduction of nitrate to dinitrogen gas, is essential for the removal of fixed nitrogen from natural and engineered ecosystems. However, community structure and activity dynamics of denitrifying bacteria in most systems are poorly understood, partially due to difficulties in identifying and quantifying...... and catalyzed fluorescent reporter deposition (CARD-FISH). The general feasibility of the approach was first tested with pure cultures of Pseudomonas stutzeri and various denitrifying and nitrate-reducing isolates. Detailed studies of probe specificity and hybridization conditions using Clone-FISH of nar...

  18. Biodegradation of hexavalent chromium (Cr+6) in wastewater using Pseudomonas sp. and Bacillus sp. bacterial strains

    Energy Technology Data Exchange (ETDEWEB)

    Qasim, Muhammad [Department of Chemical Engineering, American University of Sharjah (United Arab Emirates)

    2013-07-01

    The recovery of toxic metal compounds is a deep concern in all industries. Hexavalent chromium is particularly worrying because of its toxic influence on human health. In this paper, biodegradation of hexavalent chromium (Cr+6) present in wastewater has been studied using two different bacterial strains; Pseudomonas sp. and Bacillus sp. A chemostat (with and without recycle of cells) with 10 L liquid culture volume was used to study the substrate and the biomass cell concentrations with time. Also, the degree of substrate conversion was studied by the varying the dilution rate as an independent parameter. The dilution rate (ratio of feed flow rate to the culture volume) was varied by varying the feed volumetric rate from 110-170 mL/h for inlet hexavalent chromium concentrations of 70 mg/dm3. The results show that a chemostat with recycle gives a better performance in terms of substrate conversion than a chemostat without a recycle. Moreover, the degree of substrate conversion decreases as the dilution rate is increased. Also, Bacillus sp. was found to give higher conversions compared to pseudomonas sp.

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

    Science.gov (United States)

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

    2013-06-15

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

  20. Identification and elimination of an immunodominant T-cell epitope in recombinant immunotoxins based on Pseudomonas exotoxin A

    OpenAIRE

    Mazor, Ronit; Vassall, Aaron N.; Eberle, Jaime A.; Beers, Richard; Weldon, John E.; Venzon, David J.; Tsang, Kwong Y.; Benhar, Itai; Pastan, Ira

    2012-01-01

    Recombinant immunotoxins (RITs) are chimeric proteins that are being developed for cancer treatment. We have produced RITs that contain PE38, a portion of the bacterial protein Pseudomonas exotoxin A. Because the toxin is bacterial, it often induces neutralizing antibodies, which limit the number of treatment cycles and the effectiveness of the therapy. Because T cells are essential for antibody responses to proteins, we adopted an assay to map the CD4+ T-cell epitopes in PE38. We incubated p...

  1. [Risk factors for Pseudomonas aeruginosa infections, resistant to carbapenem].

    Science.gov (United States)

    Ghibu, Laura; Miftode, Egidia; Teodor, Andra; Bejan, Codrina; Dorobăţ, Carmen Mihaela

    2010-01-01

    Since their introduction in clinical practice,carbapenems have been among the most powerful antibiotics for treating serious infections cased by Gram-negative nosocomial pathogens, including Pseudomonas aeruginosa. The emergence of betalactamases with carbapenem-hydrolyzing activity is of major clinical concern. Pseudomonas aeruginosa is a leading cause of nosocomial infection. Risk factors for colonization with carbapenems-resistant Pseudomonas in hospital are: history of P. aeruginosa infection or colonization within the previous year, (length of hospital stay, being bedridden or in the ICU, mechanical ventilation, malignant disease, and history of chronic obstructive pulmonary disease have all been identified as independent risk factors for MDR P. aeruginosa infection. Long-term-care facilities are also reservoirs of resistant bacteria. Risk factors for colonization of LTCF residents with resistant bacteria included age > 86 years, antibiotic treatment in the previous 3 months, indwelling devices, chronic obstructive pulmonary disease, physical disability, and the particular LTCF unit.

  2. Pseudomonas species as an uncommon culprit in transbronchial needle aspiration of mediastinal lymph node

    Directory of Open Access Journals (Sweden)

    Avdhesh Bansal

    2016-01-01

    Full Text Available Mediastinal lymphadenopathy due to various infective agents such as Mycobacterium and fungus, due to sarcoidosis, lymphoma, and metastasis is often seen. Ordinary bacteria have rarely been reported to cause necrotizing, usually suppurative granulomatous reactions. We report a case of mediastinal lymphadenopathy due to Pseudomonas infection, in a patient of chronic kidney disease on maintenance hemodialysis, who presented with fever, breathlessness, and low blood pressure.

  3. Biosurfactant production by Pseudomonas strains isolated from floral nectar.

    Science.gov (United States)

    Ben Belgacem, Z; Bijttebier, S; Verreth, C; Voorspoels, S; Van de Voorde, I; Aerts, G; Willems, K A; Jacquemyn, H; Ruyters, S; Lievens, B

    2015-06-01

    To screen and identify biosurfactant-producing Pseudomonas strains isolated from floral nectar; to characterize the produced biosurfactants; and to investigate the effect of different carbon sources on biosurfactant production. Four of eight nectar Pseudomonas isolates were found to produce biosurfactants. Phylogenetic analysis based on three housekeeping genes (16S rRNA gene, rpoB and gyrB) classified the isolates into two groups, including one group closely related to Pseudomonas fluorescens and another group closely related to Pseudomonas fragi and Pseudomonas jessenii. Although our nectar pseudomonads were able to grow on a variety of water-soluble and water-immiscible carbon sources, surface active agents were only produced when using vegetable oil as sole carbon source, including olive oil, sunflower oil or waste frying sunflower oil. Structural characterization based on thin layer chromatography (TLC) and ultra high performance liquid chromatography-accurate mass mass spectrometry (UHPLC-amMS) revealed that biosurfactant activity was most probably due to the production of fatty acids (C16:0; C18:0; C18:1 and C18:2), and mono- and diglycerides thereof. Four biosurfactant-producing nectar pseudomonads were identified. The active compounds were identified as fatty acids (C16:0; C18:0; C18:1 and C18:2), and mono- and diglycerides thereof, produced by hydrolysis of triglycerides of the feedstock. Studies on biosurfactant-producing micro-organisms have mainly focused on microbes isolated from soils and aquatic environments. Here, for the first time, nectar environments were screened as a novel source for biosurfactant producers. As nectars represent harsh environments with high osmotic pressure and varying pH levels, further screening of nectar habitats for biosurfactant-producing microbes may lead to the discovery of novel biosurfactants with broad tolerance towards different environmental conditions. © 2015 The Society for Applied Microbiology.

  4. Chronic Pseudomonas aeruginosa lung infection in normal and athymic rats

    DEFF Research Database (Denmark)

    Johansen, H K; Espersen, F; Pedersen, S S

    1993-01-01

    We have compared a chronic lung infection with Pseudomonas aeruginosa embedded in alginate beads in normal and athymic rats with an acute infection with free live P. aeruginosa bacteria. The following parameters were observed and described: mortality, macroscopic and microscopic pathologic changes...

  5. Assessment of serology and spirometry and the combination of both to complement microbiological isolation for earlier detection of Pseudomonas aeruginosa infection in children with cystic fibrosis.

    Science.gov (United States)

    Kotnik Pirš, Ana; Krivec, Uroš; Simčič, Saša; Seme, Katja

    2016-11-25

    The aim of this study was to assess whether serology and spirometry and the combination of both can complement culture-based detection for earlier recognition of Pseudomonas aeruginosa infection in children with cystic fibrosis. A 4 year longitudinal prospective study that included 67 Slovenian children with cystic fibrosis with a mean age of 10.5 years was conducted. Serology, spirometry and a scoring system combining serology and spirometry were assessed and compared. Infection was confirmed with isolation of Pseudomonas aeruginosa from respiratory samples. There was a significantly positive correlation between serology and the combination of serology and spirometry and Pseudomonas aeruginosa isolation (P spirometry and Pseudomonas aeruginosa isolation (P spirometry the highest sensitivity (0.90). Both had a high negative predictive value (0.93 and 0.79 respectively). Using serology and the combination of serology and lung function measurement can be beneficial for earlier detection of infection with Pseudomonas aeruginosa in children with cystic fibrosis when done simultaneously with standard culture-based detection from respiratory samples.

  6. 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%.

  7. Biosurfactant-producing microorganism Pseudomonas sp. SB assists the phytoremediation of DDT-contaminated soil by two grass species.

    Science.gov (United States)

    Wang, Beibei; Wang, Qingling; Liu, Wuxing; Liu, Xiaoyan; Hou, Jinyu; Teng, Ying; Luo, Yongming; Christie, Peter

    2017-09-01

    Phytoremediation together with microorganisms may confer the advantages of both phytoremediation and microbial remediation of soils containing organic contaminants. In this system biosurfactants produced by Pseudomonas sp. SB may effectively help to increase the bioavailability of organic pollutants and thereby enhance their microbial degradation in soil. Plants may enhance the rhizosphere environment for microorganisms and thus promote the bioremediation of contaminants. In the present pot experiment study, dichlorodiphenyltrichloroethane (DDT) residues underwent an apparent decline after soil bioremediation compared with the original soil. The removal efficiency of fertilizer + tall fescue, fertilizer + tall fescue + Pseudomonas, fertilizer + perennial ryegrass, and fertilizer + perennial ryegrass + Pseudomonas treatments were 59.4, 65.6, 69.0, and 65.9%, respectively, and were generally higher than that in the fertilizer control (40.3%). Principal coordinates analysis (PCoA) verifies that plant species greatly affected the soil bacterial community irrespective of inoculation with Pseudomonas sp. SB. Furthermore, community composition analysis shows that Proteobacteria, Acidobacteria and Actinobacteria were the three dominant phyla in all groups. In particular, the relative abundance of Pseudomonas for fertilizer + tall fescue + Pseudomonas (0.25%) was significantly greater than fertilizer + tall fescue and this was related to the DDT removal efficiency. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Correlation between antimicrobial consumption and antimicrobial resistance of Pseudomonas aeruginosa in a hospital setting: a 10-year study.

    Science.gov (United States)

    Mladenovic-Antic, S; Kocic, B; Velickovic-Radovanovic, R; Dinic, M; Petrovic, J; Randjelovic, G; Mitic, R

    2016-10-01

    Antimicrobial resistance is one of the greatest threats to human health. One of the most important factors leading to the emergence of resistant bacteria is overuse of antibiotics. The purpose of this study was to investigate the correlation between antimicrobial usage and bacterial resistance of Pseudomonas aeruginosa (P. aeruginosa) over a 10-year period in the Clinical Center Niš, one of the biggest tertiary care hospitals in Serbia. We focused on possible relationships between the consumption of carbapenems and beta-lactam antibiotics and the rates of resistance of P. aeruginosa to carbapenems. We recorded utilization of antibiotics expressed as defined daily doses per 100 bed days (DBD). Bacterial resistance was reported as the percentage of resistant isolates (percentage of all resistant and intermediate resistant strains) among all tested isolates. A significant increasing trend in resistance was seen in imipenem (P resistance to amikacin (P resistance to imipenem in P. aeruginosa shows significance (P resistance to meropenem showed a trend towards significance (P > 0·05, Pearson r = 0·607). We found a very good correlation between the use of all beta-lactam and P. aeruginosa resistance to carbapenems (P antimicrobial resistance to carbapenems, significant correlations between the consumption of antibiotics, especially carbapenems and beta-lactams, and rates of antimicrobial resistance of P. aeruginosa to imipenem and meropenem. © 2016 John Wiley & Sons Ltd.

  9. Efflux pump inhibitors (EPIs as new antimicrobial agents against Pseudomonas aeruginosa

    Directory of Open Access Journals (Sweden)

    Momen Askoura

    2011-05-01

    Full Text Available Pseudomonas aeruginosa is an opportunistic human pathogen and one of the leading causes of nosocomial infections worldwide. The difficulty in treatment of pseudomonas infections arises from being multidrug resistant (MDR and exhibits resistance to most antimicrobial agents due to the expression of different mechanisms overcoming their effects. Of these resistance mechanisms, the active efflux pumps in Pseudomonas aeruginosa that belong to the resistance nodulation division (RND plays a very important role in extruding the antibiotics outside the bacterial cells providing a protective means against their antibacterial activity. Beside its role against the antimicrobial agents, these pumps can extrude biocides, detergents, and other metabolic inhibitors. It is clear that efflux pumps can be targets for new antimicrobial agents. Peptidomimetic compounds such as phenylalanine arginyl β-naphthylamide (PAβN have been introduced as efflux pump inhibitors (EPIs; their mechanism of action is through competitive inhibition with antibiotics on the efflux pump resulting in increased intracellular concentration of antibiotic, hence, restoring its antibacterial activity. The advantage of EPIs is the difficulty to develop bacterial resistance against them, but the disadvantage is their toxic property hindering their clinical application. The structure activity relationship of these compounds showed other derivatives from PAβN that are higher in their activity with higher solubility in biological fluids and decreased toxicity level. This raises further questions on how can we compact Pseudomonas infections. Of particular importance, the recent resurgence in the use of older antibiotics such as polymyxins and probably applying stricter control measures in order to prevent their spread in clinical sittings.

  10. Development of a low cost, low environmental impact process for disposal of nitrate wastes

    International Nuclear Information System (INIS)

    Napier, J.M.

    1975-01-01

    A uranium recycle process in the Y-12 Plant generates nitrate ions which must be discarded. Scrap enriched uranium is dissolved in nitric acid and solvent extracted to remove impurities from the uranium. Aluminum nitrate is also used in the process to remove the purified uranium from the solvent extraction process. Dilute nitric acid, aluminum nitrate, and metallic impurities must be discarded from this process. A program was started to develop a low cost, low environmental impact process for disposal of these nitrate wastes. Several disposal methods were considered. A process was selected which included: distillation and recycle of nitric acid; crystallization and recycle of aluminum nitrate; and biodegradation of the remaining nitrate waste solutions. For this presentation, only the biodegradation process will be discussed. A colony of Pseudomonas stutzeri, which is capable of using the nitrate ion as the oxygen supply, was used. An excess of organic material was used to insure that the maximum amount of nitrate was destroyed

  11. Molecular confirmation of shampoo as the putative source of Pseudomonas aeruginosa-induced postgrooming furunculosis in a dog.

    Science.gov (United States)

    Tham, Heng L; Jacob, Megan E; Bizikova, Petra

    2016-08-01

    An acute onset furunculosis due to Pseudomonas aeruginosa following grooming is a well recognized entity. Although contaminated shampoos have been suspected to be the source of the infection, a molecular confirmation of this association has been missing. This case report describes a dog with postgrooming furunculosis in which Pseudomonas aeruginosa with an identical genetic fingerprint was isolated from the skin lesions as well as from the shampoo used prior to the disease onset. The dog presented for lethargy, anorexia, pain and rapidly progressing skin lesions consistent with haemorrhagic papules, pustules, coalescing ulcers and crusts localized to the dorsal and lateral aspects of the thorax and gluteal region, which developed within 24 h after a bath. Cytology demonstrated suppurative inflammation with occasional intracellular rod-shaped bacteria. Bacterial culture from skin lesions and the shampoo bottle yielded Pseudomonas aeruginosa with an identical pulsed-field gel electrophoresis pattern. Treatment with oral ciprofloxacin and topical antimicrobial shampoo resulted in a complete resolution of skin lesions within eight weeks. Our clinical investigation suggests a link between Pseudomonas-contaminated shampoo and development of postgrooming furunculosis, and underscores the need for hygienic management of shampoos to help limit this disease. © 2016 ESVD and ACVD.

  12. Recognition of six additional cystoviruses: Pseudomonas virus phi6 is no longer the sole species of the family Cystoviridae.

    Science.gov (United States)

    Mäntynen, Sari; Sundberg, Lotta-Riina; Poranen, Minna M

    2018-04-01

    Cystoviridae is a family of bacterial viruses (bacteriophages) with a tri-segmented dsRNA genome. It includes a single genus Cystovirus, which has presently only one recognised virus species, Pseudomonas virus phi6. However, a large number of additional dsRNA phages have been isolated from various environmental samples, indicating that such viruses are more widespread and abundant than previously recognised. Six of the additional dsRNA phage isolates (Pseudomonas phages phi8, phi12, phi13, phi2954, phiNN and phiYY) have been fully sequenced. They all infect Pseudomonas species, primarily plant pathogenic Pseudomonas syringae strains. Due to the notable genetic and structural similarities with Pseudomonas phage phi6, we propose that these viruses should be included into the Cystovirus genus (and consequently into the Cystoviridae family). Here, we present an updated taxonomy of the family Cystoviridae and give a short overview of the properties of the type member phi6 as well as the putative new members of the family.

  13. Comparative In Vitro Efficacy of Doripenem and Imipenem Against Multi-Drug Resistant Pseudomonas aeruginosa

    International Nuclear Information System (INIS)

    Wali, N.; Mirza, I. A.

    2016-01-01

    Objective: To compare the in vitro efficacy of doripenem and imipenem against multi-drug resistant (MDR) Pseudomonas aeruginosa from various clinical specimens. Study Design: Descriptive cross-sectional study. Place and Duration of Study: Department of Microbiology, Armed Forces Institute of Pathology, Rawalpindi, from November 2012 to November 2013. Methodology: MDR Pseudomonas aeruginosa isolates from various clinical samples were included in the study. Susceptibility of Pseudomonas aeruginosa against doripenem and imipenem was performed by E-test strip and agar dilution methods. The results were interpreted as recommended by Clinical Laboratory Standard Institute (CLSI) guidelines. Results: The maximum number of Pseudomonas aeruginosa were isolated from pure pus and pus swabs. In vitro efficacy of doripenem was found to be more effective as compared to imipenem against MDR Pseudomonas aeruginosa with both E-test strip and agar dilution methods. Overall, p-values of 0.014 and 0.037 were observed when susceptibility patterns of doripenem and imipenem were evaluated with E-test strip and agar dilution methods. Conclusion: In vitro efficacy of doripenem was found to be better against MDR Pseudomonas aeruginosa as compared to imipenem when tested by both E-test and agar dilution methods. (author)

  14. 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. Copyright © 2015 Elsevier Inc. All rights reserved.

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

    African Journals Online (AJOL)

    Michael Horsfall

    ABSTRACT: The potential of local strains of microorganism (Pseudomonas fluorescens) in polyhydroxbutyrate production ... The demand for the use of biopolymers ... This work therefore investigates the production of polyhydroxybutyrate from.

  16. 40 CFR 180.1108 - Delta endotoxin of Bacillus thuringiensis variety San Diego encapsulated into killed Pseudomonas...

    Science.gov (United States)

    2010-07-01

    ... thuringiensis variety San Diego encapsulated into killed Pseudomonas fluorescens; exemption from the requirement... into killed Pseudomonas fluorescens; exemption from the requirement of a tolerance. The delta endotoxin of Bacillus thuringiensis variety San Diego encapsulated into killed Pseudomonas fluorescens is...

  17. 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...

  18. Biosynthesis of silver nanoparticles by Pseudomonas spp. isolated from effluent of an electroplating industry.

    Science.gov (United States)

    Punjabi, Kapil; Yedurkar, Snehal; Doshi, Sejal; Deshapnde, Sunita; Vaidya, Shashikant

    2017-08-01

    The aim of this study was to isolate and screen bacteria from soil and effluent of electroplating industries for the synthesis of silver nanoparticles and characterize the potential isolate. Soil and effluent of electroplating industries from Mumbai were screened for bacteria capable of synthesizing silver nanoparticles. From two soils and eight effluent samples 20 bacterial isolates were obtained, of these, one was found to synthesize silver nanoparticles. Synthesis of silver nanoparticle by bacteria was confirmed by undertaking characterization studies of nanoparticles that involved spectroscopy and electron microscopic techniques. The potential bacteria was found to be Gram-negative short rods with its biochemical test indicating Pseudomonas spp . Molecular characterization of the isolate by 16S r DNA sequencing was carried out which confirmed its relation to Pseudomonas hibiscicola ATCC 19867. Stable nanoparticles synthesized were 50 nm in size and variable shapes as seen in SEM micrographs. The XRD and FTIR confirmed the crystalline structure of nanoparticles and presence of biomolecules mainly proteins as agents for reduction and capping of nanoparticles. The study demonstrates synthesis of nanoparticles by bacteria from effluent of electroplating industry. This can be used for large scale synthesis of nanoparticles by cost effective and environmentally benign mode of synthesis.

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

    Directory of Open Access Journals (Sweden)

    Edilberto Silva Gómez

    2010-09-01

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

  20. The role of gluconate production by Pseudomonas spp. in the mineralization and bioavailability of calcium-phytate to Nicotiana tabacum.

    Science.gov (United States)

    Giles, Courtney D; Hsu, Pei-Chun Lisa; Richardson, Alan E; Hurst, Mark R H; Hill, Jane E

    2015-12-01

    Organic phosphorus (P) is abundant in most soils but is largely unavailable to plants. Pseudomonas spp. can improve the availability of P to plants through the production of phytases and organic anions. Gluconate is a major component of Pseudomonas organic anion production and may therefore play an important role in the mineralization of insoluble organic P forms such as calcium-phytate (CaIHP). Organic anion and phytase production was characterized in 2 Pseudomonas spp. soil isolates (CCAR59, Ha200) and an isogenic mutant of strain Ha200, which lacked a functional glucose dehydrogenase (Gcd) gene (strain Ha200 gcd::Tn5B8). Wild-type and mutant strains of Pseudomonas spp. were evaluated for their ability to solubilize and hydrolyze CaIHP and to promote the growth and assimilation of P by tobacco plants. Gluconate, 2-keto-gluconate, pyruvate, ascorbate, acetate, and formate were detected in Pseudomonas spp. supernatants. Wild-type pseudomonads containing a functional gcd could produce gluconate and mineralize CaIHP, whereas the isogenic mutant could not. Inoculation with Pseudomonas improved the bioavailability of CaIHP to tobacco plants, but there was no difference in plant growth response due to Gcd function. Gcd function is required for the mineralization of CaIHP in vitro; however, further studies will be needed to quantify the relative contribution of specific organic anions such as gluconate to plant growth promotion by soil pseudomonads.

  1. Intramolecular electron transfer in cytochrome cd(1) nitrite reductase from Pseudomonas stutzeri; kinetics and thermodynamics

    DEFF Research Database (Denmark)

    Farver, Ole; Kroneck, Peter M H; Zumft, Walter G

    2002-01-01

    determined over a 277-313 K temperature range and yielded both equilibrium standard enthalpy and entropy changes as well as activation parameters of the specific rate constants. The significance of these parameters obtained at low degree of reduction of the enzyme is discussed and compared with earlier...

  2. Balneotherapy is a potential risk factor for Pseudomonas aeruginosa colonization

    Directory of Open Access Journals (Sweden)

    Gabriela Deutsch

    Full Text Available ABSTRACT The practice of immersion in burn patient has been abandoned in many parts of the world but in Brazil it is still common. The aim of this study was to ascertain if balneotherapy is a risk factor for Pseudomonas aeruginosa colonization in thermally injured patients. Eighteen patients from a Burn Center were studied for 14 weeks for Pseudomonas aeruginosa. Samples were collected by swabbing the exudate of wounds, before and after giving bath to the patients and from balneotherapy table. Pulsed-field gel electrophoresis was used to determine bacterial genetic relatedness. Thirty-seven P. aeruginosa isolates were detected from 292 swabs collected from patients' burn surface area and from the balneotherapy table. Profile analysis of P. aeruginosa DNA fragmentation showed 10 clones among the 37 strains analyzed. Type A is the most prevalent clone, with 23 strains distributed into eight subtypes. These were present in the swabs collected, before and after the patients' bath, from the surface of the bath table, suggesting that there was cross-contamination between the patients in different ways. This work demonstrates that balneotherapy is a risk factor in the Burn Center studied, because the same clone was found among P. aeruginosa isolates collected at various points and times.

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

    Directory of Open Access Journals (Sweden)

    Fatimah Fatimah

    2012-02-01

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

  4. Garlic as an inhibitor of Pseudomonas aeruginosa quorum sensing in cystic fibrosis--a pilot randomized controlled trial

    DEFF Research Database (Denmark)

    Smyth, Alan R; Cifelli, Paramita M; Ortori, Catharine A

    2010-01-01

    Pseudomonas aeruginosa forms biofilms in the cystic fibrosis lung. Quorum sensing (QS) controls biofilm maturation, immune evasion, antibiotic tolerance and virulence factor production. Garlic shows QS inhibitory activity in vitro and in animal models. We report the first clinical trial in man of...

  5. Potencial de pseudomonas spp. fluorescentes para biocontrole de alternaria ricini em mamoneira Potential of fluorescent pseudomonas spp. For biological control of alternaria ricini on castorbean

    Directory of Open Access Journals (Sweden)

    Francisco de A.G. da Silva

    1998-06-01

    Full Text Available The potential of fluorescent Pseudomonas spp. to control Alternaria leaf spot on castorbean, caused by Alternaria ricini, was studied under greenhouse conditions. Two periods for antagonist applications were tested: 48h before and simultaneously to the pathogen inoculation. Among the antagonists tested JA4 and BJ22 were the most effectives showing disease severity reduction of 20.9% and 17.8% respectively, when applied simultaneously. The effect of Pseudomonas spp. on the micelial growth and sporulation was also studied throughout three different methods (funel, streak and celophane. Inhibition of micelial growth and sporulation was observed. There was no correlation between in vitro and in vivo data. Antibiosis was showed as a mode of action for Pseudomonas spp. in relation to Alternaria ricini. Ultrastructural studies confirmed the inhibition of spore germination by the bacteria.

  6. Pseudomonas chlororaphis Produces Two Distinct R-Tailocins That Contribute to Bacterial Competition in Biofilms and on Roots.

    Science.gov (United States)

    Dorosky, Robert J; Yu, Jun Myoung; Pierson, Leland S; Pierson, Elizabeth A

    2017-08-01

    R-type tailocins are high-molecular-weight bacteriocins that resemble bacteriophage tails and are encoded within the genomes of many Pseudomonas species. In this study, analysis of the P. chlororaphis 30-84 R-tailocin gene cluster revealed that it contains the structural components to produce two R-tailocins of different ancestral origins. Two distinct R-tailocin populations differing in length were observed in UV-induced lysates of P. chlororaphis 30-84 via transmission electron microscopy. Mutants defective in the production of one or both R-tailocins demonstrated that the killing spectrum of each tailocin is limited to Pseudomonas species. The spectra of pseudomonads killed by the two R-tailocins differed, although a few Pseudomonas species were either killed by or insusceptible to both tailocins. Tailocin release was disrupted by deletion of the holin gene within the tailocin gene cluster, demonstrating that the lysis cassette is required for the release of both R-tailocins. The loss of functional tailocin production reduced the ability of P. chlororaphis 30-84 to compete with an R-tailocin-sensitive strain within biofilms and rhizosphere communities. Our study demonstrates that Pseudomonas species can produce more than one functional R-tailocin particle sharing the same lysis cassette but differing in their killing spectra. This study provides evidence for the role of R-tailocins as determinants of bacterial competition among plant-associated Pseudomonas in biofilms and the rhizosphere. IMPORTANCE Recent studies have identified R-tailocin gene clusters potentially encoding more than one R-tailocin within the genomes of plant-associated Pseudomonas but have not demonstrated that more than one particle is produced or the ecological significance of the production of multiple R-tailocins. This study demonstrates for the first time that Pseudomonas strains can produce two distinct R-tailocins with different killing spectra, both of which contribute to bacterial

  7. Improved Performance of Pseudomonas fluorescens lipase by covalent immobilization onto Amberzyme

    NARCIS (Netherlands)

    Aslan, Yakup; Handayani, Nurrahmi; Stavila, Erythrina; Loos, Katja

    2013-01-01

    Objective: In this study, the conditions of covalent immobilization of Pseudomonas fluorescens lipase onto an oxirane-activated support (Amberzyme) were optimized to obtain a high activity yield. Furthermore, the operational and storage stabilities of immobilized lipase were tested. Methods: Optimum

  8. A case of orbital apex syndrome due to Pseudomonas aeruginosa infection

    Directory of Open Access Journals (Sweden)

    Takeshi Kusunoki

    2011-11-01

    Full Text Available Orbital apex syndrome is commonly been thought to have a poor prognosis. Many cases of this syndrome have been reported to be caused by paranasal sinus mycosis. We encountered a very rare case (60-year-old woman of sinusitis with orbital apex syndrome due to Pseudomonas aeruginosa infection. She had received insulin and dialysis for diabtes and diabetic nephropathy, moreover anticoagulants after heart by-pass surgery. She underwent endoscopic sinus operation and was treated with antibiotics, but her loss of left vision did not improve. Recently, sinusitis cases due to Pseudomonas aeruginosa were reported to be a increasing. Therefore, we should consider the possibility of Pseudomonas aeruginosa as well as mycosis as infections of the sinus, especially inpatients who are immunocompromised body.

  9. Structure of a putative acetyltransferase (PA1377) from Pseudomonas aeruginosa

    International Nuclear Information System (INIS)

    Davies, Anna M.; Tata, Renée; Chauviac, François-Xavier; Sutton, Brian J.; Brown, Paul R.

    2008-01-01

    The crystal structure of an acetyltransferase encoded by the gene PA1377 from Pseudomonas aeruginosa has been determined at 2.25 Å resolution. Comparison with a related acetyltransferase revealed a structural difference in the active site that was taken to reflect a difference in substrate binding and/or specificity between the two enzymes. Gene PA1377 from Pseudomonas aeruginosa encodes a 177-amino-acid conserved hypothetical protein of unknown function. The structure of this protein (termed pitax) has been solved in space group I222 to 2.25 Å resolution. Pitax belongs to the GCN5-related N-acetyltransferase family and contains all four sequence motifs conserved among family members. The β-strand structure in one of these motifs (motif A) is disrupted, which is believed to affect binding of the substrate that accepts the acetyl group from acetyl-CoA

  10. 40 CFR 180.1212 - Pseudomonas chlororaphis Strain 63-28; exemption from the requirement of a tolerance.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Pseudomonas chlororaphis Strain 63-28... RESIDUES IN FOOD Exemptions From Tolerances § 180.1212 Pseudomonas chlororaphis Strain 63-28; exemption... for residues of the microbial pesticide Pseudomonas chlororaphis Strain 63-28 in or on all food...

  11. Pseudomonas putida growing at low temperature shows increased levels of CrcZ and CrcY sRNAs, leading to reduced Crc-dependent catabolite repression.

    Science.gov (United States)

    Fonseca, Pilar; Moreno, Renata; Rojo, Fernando

    2013-01-01

    The Crc protein of Pseudomonas inhibits the expression of genes involved in the transport and assimilation of a number of non-preferred carbon sources when preferred substrates are available, thus coordinating carbon metabolism. Crc acts by binding to target mRNAs, inhibiting their translation. In Pseudomonas putida, the amount of free Crc available is controlled by two sRNAs, CrcY and CrcZ, which bind to and sequester Crc. The levels of these sRNAs vary according to metabolic conditions. Pseudomonas putida grows optimally at 30°C, but can also thrive at 10°C. The present work shows that when cells grow exponentially at 10°C, the repressive effect of Crc on many genes is significantly reduced compared with that seen at 30°C. Total Crc levels were similar at both temperatures, but those of CrcZ and CrcY were significantly higher at 10°C. Therefore, Crc-mediated repression may, at least in part, be reduced at 10°C because the fraction of Crc protein sequestered by CrcZ and CrcY is larger, reducing the amount of free Crc available to bind its targets. This may help P. putida to face cold stress. The results reported might help understanding the behaviour of this bacterium in bioremediation or rhizoremediation strategies at low temperatures. © 2012 Society for Applied Microbiology and Blackwell Publishing Ltd.

  12. Accelerated storage testing of freeze-dried Pseudomonas ...

    African Journals Online (AJOL)

    Accelerated storage testing of freeze-dried Pseudomonas fluorescens BTP1, ... of all P. fluorescens strains were not significantly different and thermal inactivation ... useful to the development of improved reference materials and samples held ...

  13. An Enterotoxin-Like Binary Protein from Pseudomonas protegens with Potent Nematicidal Activity.

    Science.gov (United States)

    Wei, Jun-Zhi; Siehl, Daniel L; Hou, Zhenglin; Rosen, Barbara; Oral, Jarred; Taylor, Christopher G; Wu, Gusui

    2017-10-01

    Soil microbes are a major food source for free-living soil nematodes. It is known that certain soil bacteria have evolved systems to combat predation. We identified the nematode-antagonistic Pseudomonas protegens strain 15G2 from screening of microbes. Through protein purification we identified a binary protein, designated Pp-ANP, which is responsible for the nematicidal activity. This binary protein inhibits Caenorhabditis elegans growth and development by arresting larvae at the L1 stage and killing older-staged worms. The two subunits, Pp-ANP1a and Pp-ANP2a, are active when reconstituted from separate expression in Escherichia coli The binary toxin also shows strong nematicidal activity against three other free-living nematodes ( Pristionchus pacificus , Panagrellus redivivus , and Acrobeloides sp.), but we did not find any activity against insects and fungi under test conditions, indicating specificity for nematodes. Pp-ANP1a has no significant identity to any known proteins, while Pp-ANP2a shows ∼30% identity to E. coli heat-labile enterotoxin (LT) subunit A and cholera toxin (CT) subunit A. Protein modeling indicates that Pp-ANP2a is structurally similar to CT/LT and likely acts as an ADP-ribosyltransferase. Despite the similarity, Pp-ANP shows several characteristics distinct from CT/LT toxins. Our results indicate that Pp-ANP is a new enterotoxin-like binary toxin with potent and specific activity to nematodes. The potency and specificity of Pp-ANP suggest applications in controlling parasitic nematodes and open an avenue for further research on its mechanism of action and role in bacterium-nematode interaction. IMPORTANCE This study reports the discovery of a new enterotoxin-like binary protein, Pp-ANP, from a Pseudomonas protegens strain. Pp-ANP shows strong nematicidal activity against Caenorhabditis elegans larvae and older-staged worms. It also shows strong activity on other free-living nematodes ( Pristionchus pacificus , Panagrellus redivivus , and

  14. Capsule production by Pseudomonas aeruginosa

    Energy Technology Data Exchange (ETDEWEB)

    Lynn, A.R.

    1984-01-01

    Mucoid strains of Pseudomonas aeruginosa, associated almost exclusively with chronic respiratory infections in patients with cystic fibrosis, possess a capsule composed of alginic acid similar to one produced by Azotobacter vinelandii. Recent reports have provided evidence that the biosynthetic pathway for alginate in P. aeruginosa may differ from the pathway proposed for A. vinelandii in that synthesis in P. aeruginosa may occur by way of the Entner-Doudoroff pathway. Incorporation of isotope from (6-/sup 14/C)glucose into alginate by both P. aueroginosa and A. vinelandii was 10-fold greater than that from either (1-/sup 14/C)/sup -/ or (2-/sup 14/C)glucose, indicating preferential utilization of the bottom half of the glucose molecule for alginate biosynthesis. These data strongly suggest that the Entner-Doudoroff pathway plays a major role in alginate synthesis in both P. aeruginosa and A. vinelandii. The enzymes of carbohydrate metabolism in mucoid strains of P. aeruginosa appear to be unchanged whether alignate is actively produced or not and activities do not differ significantly from nonmucoid strain PAO.

  15. 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...

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

    Science.gov (United States)

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

    2011-01-01

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

  17. Pseudomonas oceani sp. nov., isolated from deep seawater.

    Science.gov (United States)

    Wang, Ming-Qing; Sun, Li

    2016-10-01

    In this study, we identified a novel Gram-stain-negative, aerobic, motile, and rod-shaped bacterium, strain KX 20T, isolated from the deep seawater in Okinawa Trough, northwestern Pacific Ocean. Phylogenetic analysis based on 16S rRNA gene sequence showed that strain KX 20T was related to members of the genus Pseudomonas and shares the highest sequence identities with Pseudomonas aestusnigri CECT 8317T (99.4 %) and Pseudomonas pachastrellae JCM 12285T (98.5 %). The 16S rRNA gene sequence identities between strain KX 20T and other members of the genus Pseudomonaswere below 96.6 %. The gyrB and rpoD genes of strain KX 20T shared 82.0 to 89.3 % sequence identity with the gyrB and rpoD genes of the closest phylogenetic neighbours of KX 20T. The predominant cellular fatty acids of strain KX 20T were summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c) (29.2 %), C16 : 0 (24.5 %), summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c) (21.5 %) and C12 : 0 (8.2 %). The major polar lipids of strain KX 20T were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and unknown phospholipids. The genomic DNA G+C content of strain KX 20T was 62.9 mol%. On the basis of phylogenetic analysis and phenotypic characteristics, a novel species, Pseudomonas oceani sp. nov. is proposed. The type strain is KX 20T (=CGMCC 1.15195T=DSM 100277T).

  18. Degradation of carbazole, dibenzothiophene, and dibenzofuran at low temperature by Pseudomonas sp. strain C3211.

    Science.gov (United States)

    Jensen, Anne-Mette; Finster, Kai Waldemar; Karlson, Ulrich

    2003-04-01

    Pseudomonas sp. strain C3211 was isolated from a temperate climate soil contaminated with creosote. This strain was able to degrade carbazole, dibenzothiophene and dibenzofuran at 10 degrees C with acetone as a co-substrate. When dibenzothiophene was degraded by strain C3211, an orange compound, which absorbed at 472 nm, accumulated in the medium. Degradation of dibenzofuran was followed by accumulation of a yellowish compound, absorbing at 462 nm. The temperature optimum of strain C3211 for degradation of dibenzothiophene and dibenzofuran was at 20 to 21 degrees C, while the maximum temperature for degradation was at 27 degrees C. Both compounds were degraded at 4 degrees C. Degradation at 10 degrees C was faster than degradation at 25 degrees C. This indicates that strain C3211 is adapted to life at low temperatures.

  19. Pseudomonas aeruginosa inhibits the growth of Cryptococcus species.

    Science.gov (United States)

    Rella, Antonella; Yang, Mo Wei; Gruber, Jordon; Montagna, Maria Teresa; Luberto, Chiara; Zhang, Yong-Mei; Del Poeta, Maurizio

    2012-06-01

    Pseudomonas aeruginosa is a ubiquitous and opportunistic bacterium that inhibits the growth of different microorganisms, including Gram-positive bacteria and fungi such as Candida spp. and Aspergillus fumigatus. In this study, we investigated the interaction between P. aeruginosa and Cryptococcus spp. We found that P. aeruginosa PA14 and, to a lesser extent, PAO1 significantly inhibited the growth of Cryptococcus spp. The inhibition of growth was observed on solid medium by the visualization of a zone of inhibition of yeast growth and in liquid culture by viable cell counting. Interestingly, such inhibition was only observed when P. aeruginosa and Cryptococcus were co-cultured. Minimal inhibition was observed when cell-cell contact was prevented using a separation membrane, suggesting that cell contact is required for inhibition. Using mutant strains of Pseudomonas quinoline signaling, we showed that P. aeruginosa inhibited the growth of Cryptococcus spp. by producing antifungal molecules pyocyanin, a redox-active phenazine, and 2-heptyl-3,4-dihydroxyquinoline (PQS), an extracellular quorum-sensing signal. Because both P. aeruginosa and Cryptococcus neoformans are commonly found in lung infections of immunocompromised patients, this study may have important implication for the interaction of these microbes in both an ecological and a clinical point of view.

  20. Synthesis, characterization and immunological properties of LPS-based conjugate vaccine composed of O-polysaccharide from pseudomonas aeruginosa IATS 10 bound to recombinant exoprotein A

    International Nuclear Information System (INIS)

    Abu-baker, N. F.; Masoud, H. A.; Jaber, B. M.

    2008-01-01

    Pseudomonas aeruginosa is an improtant opportunistic pathogen that can cause infection in immunocompromised patient. Lipopolysaccharide (LPS), the major surface antigen of P. aeruginosa, is immunogenic and elieits protective antibodies in animals. The O-polysaccharids (O-PS) from international Antigenic typing Scheme (IATS) 10, the antigenic determinant of LPS, was coupled to recombinant exoprotein A (rPA) through adipic acid dihydrazide (ADH) mediated by carbodiimide condensation reaction. Mice were immunized with the conjugate emulsifield with monophosphoryl lipid A-trehalose dicorynomycolate (MPL-T) and freund's adjuvants. The conjiugate emulsified with MPL-T adjuvant elicited the highest level of IgG and IgM followed by freuns's adjuvant. IgG titers using both MPL-T and freund's adjuvants were recorded to be higher than IgM titers after the second post of the immunization. Immunization of mice with the prepared conjugates emulsified with MPL-T and freund's adjvaided provide high level of protection (100%) against ten times the LD50 of homologous strain of P. aeruginsoa. the elicited high IgG level and the in vivo protection test results provided good evidences for the possible protection of the conjugate aginst subsequent infection with the pathogen. These findings will enable us to use it as protective vaccine candidate (authors).

  1. Improvement in solvent tolerance by exogenous glycerol in Pseudomonas sp. BCNU 106.

    Science.gov (United States)

    Choi, H J; Lim, B R; Park, Y J; Joo, W H

    2017-08-01

    Solvent hypertolerant Pseudomonas sp. BCNU 106 still has some underlying growth limitation in solvents. Therefore, efficient mass cultivation methods are needed to pursue its applications in biotechnology. Pseudomonas sp. BCNU 106 was cultured in a medium supplemented with 0·05 mol l -1 glycerol and cell survival was monitored during its cultivation in the presence of 1% (v/v) toluene. Exogenously supplemented glycerol provided more protection against damage caused by toluene stress and conferred higher solvent tolerance of Pseudomonas sp. BCNU 106 to toluene compared to control Pseudomonas sp. BCNU 106 without the supplementation of glycerol. This low-cost mass cultivation method can be used to efficiently apply solvent-tolerant bacteria in biotransformation and biodegradation. Protection against toluene and improvement in bacterial cell growth by supplementation of glycerol in the presence of toluene are demonstrated in this study. This result can be used to solve growth-related hindrances of solvent-tolerant bacteria and establish their low-cost mass cultivation, thereby broadening their industrial and environmental applications. © 2017 The Society for Applied Microbiology.

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

    African Journals Online (AJOL)

    Further characterization of biosurfactant using Fourier transform infrared spectroscopy (FTIR) revealed it as a rhamnolipid. Keywords: Mangrove ecosystems, Pseudomonas aeruginosa, biosurfactant, critical micelle concentration (CMC), FT-IR fourier transform infrared spectroscopy (FTIR). African Journal of Biotechnology, ...

  3. Bioreporter pseudomonas fluorescens HK44 immobilized in a silica matrix

    Directory of Open Access Journals (Sweden)

    Trogl J.

    2003-01-01

    Full Text Available The bioluminescent bioreporter Pseudomonas fluorescens HK44, the whole cell bacterial biosensor that responds to naphthalene and its metabolites via the production of visible light, was immobilized into a silica matrix by the sol-gel technique. The bioluminescence intensities were measured in the maximum of the bioluminescence band at X = 500 nm. The immobilized cells (>105 cells per g silica matrix produced light after induction by salicylate (cone. > 10 g/l, naphthalene and aminobenzoic acid. The bioluminescence intensities induced by 2,3-dihydroxynaphthalene 3-hydroxybenzoic acid and 4-hydroxybenzoic acid were comparable to a negative control. The cells in the silica layers on glass slides produced light in response to the presence of an inductor at least 8 months after immobilization, and >50 induction cycles. The results showed that these test slides could be used as assays for the multiple determination of water pollution.

  4. An Antipersister Strategy for Treatment of Chronic Pseudomonas aeruginosa Infections.

    Science.gov (United States)

    Koeva, Martina; Gutu, Alina D; Hebert, Wesley; Wager, Jeffrey D; Yonker, Lael M; O'Toole, George A; Ausubel, Frederick M; Moskowitz, Samuel M; Joseph-McCarthy, Diane

    2017-12-01

    Bacterial persisters are a quasidormant subpopulation of cells that are tolerant to antibiotic treatment. The combination of the aminoglycoside tobramycin with fumarate as an antibacterial potentiator utilizes an antipersister strategy that is aimed at reducing recurrent Pseudomonas aeruginosa infections by enhancing the killing of P. aeruginosa persisters. Stationary-phase cultures of P. aeruginosa were used to generate persister cells. A range of tobramycin concentrations was tested with a range of metabolite concentrations to determine the potentiation effect of the metabolite under a variety of conditions, including a range of pH values and in the presence of azithromycin or cystic fibrosis (CF) patient sputum. In addition, 96-well dish biofilm and colony biofilm assays were performed, and the cytotoxicity of the tobramycin-fumarate combination was determined utilizing a lactate dehydrogenase (LDH) assay. Enhanced killing of up to 6 orders of magnitude of P. aeruginosa persisters over a range of CF isolates, including mucoid and nonmucoid strains, was observed for the tobramycin-fumarate combination compared to killing with tobramycin alone. Furthermore, significant fumarate-mediated potentiation was seen in the presence of azithromycin or CF patient sputum. Fumarate also reduced the cytotoxicity of tobramycin-treated P. aeruginosa to human epithelial airway cells. Finally, in mucoid and nonmucoid CF isolates, complete eradication of P. aeruginosa biofilm was observed in the colony biofilm assay due to fumarate potentiation. These data suggest that a combination of tobramycin with fumarate as an antibacterial potentiator may be an attractive therapeutic for eliminating recurrent P. aeruginosa infections in CF patients through the eradication of bacterial persisters. Copyright © 2017 American Society for Microbiology.

  5. A Pseudomonas aeruginosa toxin that hijacks the host ubiquitin proteolytic system.

    Directory of Open Access Journals (Sweden)

    Jennifer M Bomberger

    2011-03-01

    Full Text Available Pseudomonas aeruginosa (P. aeruginosa is an opportunistic pathogen chronically infecting the lungs of patients with chronic obstructive pulmonary disease (COPD, pneumonia, cystic fibrosis (CF, and bronchiectasis. Cif (PA2934, a bacterial toxin secreted in outer membrane vesicles (OMV by P. aeruginosa, reduces CFTR-mediated chloride secretion by human airway epithelial cells, a key driving force for mucociliary clearance. The aim of this study was to investigate the mechanism whereby Cif reduces CFTR-mediated chloride secretion. Cif redirected endocytosed CFTR from recycling endosomes to lysosomes by stabilizing an inhibitory effect of G3BP1 on the deubiquitinating enzyme (DUB, USP10, thereby reducing USP10-mediated deubiquitination of CFTR and increasing the degradation of CFTR in lysosomes. This is the first example of a bacterial toxin that regulates the activity of a host DUB. These data suggest that the ability of P. aeruginosa to chronically infect the lungs of patients with COPD, pneumonia, CF, and bronchiectasis is due in part to the secretion of OMV containing Cif, which inhibits CFTR-mediated chloride secretion and thereby reduces the mucociliary clearance of pathogens.

  6. The effects of hyperosmosis or high pH on a dual-species biofilm of Enterococcus faecalis and Pseudomonas aeruginosa : an in vitro study

    NARCIS (Netherlands)

    van der Waal, S. V.; van der Sluis, L. W. M.; Ozok, A. R.; Exterkate, R. A. M.; van Marle, J.; Wesselink, P. R.; de Soet, J. J.

    2011-01-01

    van der Waal SV, van der Sluis LWM, Ozok AR, Exterkate RAM, van Marle J, Wesselink PR, de Soet JJ. The effects of hyperosmosis or high pH on a dual-species biofilm of Enterococcus faecalis and Pseudomonas aeruginosa: an in vitro study. International Endodontic Journal, 44, 11101117, 2011. Aim To

  7. Targeting quorum sensing in Pseudomonas aeruginosa biofilms

    DEFF Research Database (Denmark)

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

    2013-01-01

    Bacterial resistance to conventional antibiotics combined with an increasing acknowledgement of the role of biofilms in chronic infections has led to a growing interest in new antimicrobial strategies that target the biofilm mode of growth. In the aggregated biofilm mode, cell-to-cell communication...... alternative antibacterial strategies. Here, we review state of the art research of quorum sensing inhibitors against the opportunistic human pathogen Pseudomonas aeruginosa, which is found in a number of biofilm-associated infections and identified as the predominant organism infecting the lungs of cystic...

  8. Anti-pseudomona and Anti-bacilli Activity of Some Medicinal Plants of Iran

    Directory of Open Access Journals (Sweden)

    Gholam Hosein Shahidi Bonjar

    2003-10-01

    Full Text Available The use of plants in treatment of burns, dermatophytes, and infectious diseases is common in traditional medicine of Iran. Based on ethno pharmacological and taxonomic information, antibacterial activities of methanol extracts of some medicinal plants of Iran were determined by In Vitro bioassays using agar diffusion-method against standard strains of Pseudomonas aeruginosa, P. fluorescens, Bacillus subtilis, B. cereus and B. pumilis at 20 mg/ml. From 180 plant species of 72 families, 78 species (43.3% in 42 families (58.3% showed antibacterial activities against B. cereus (88.4%, B. subtilis (39.7%, B. pumilis (37.1%, P. fluorescens (37.1% and P. aeruginos (10.2%. The most active plant families were Apiaceae, Compositae and Labiatae with 9, 8 and 7 active plant species respectively. Minimum inhibitory concentrations (MIC of the active plants were determined using two fold serial dilutions. Most active plant against Bacilli was Myrtus communis L. with MIC of 1.87 mg/ml. For Pseudomonas species, Dianthus caryophyllus L. and Terminalia chebula (Gaertner Retz. were more active with the MIC of 0.46 mg/ml for P. fluorescens and of 1.87 mg/ml for P. aeruginosa respectively.

  9. Pseudomonas aeruginosa: disseminação de resistência antimicrobiana em efluente hospitalar e água superficial Pseudomonas aeruginosa: spread of antimicrobial resistance in hospital effluent and surface water

    Directory of Open Access Journals (Sweden)

    Daiane Bopp Fuentefria

    2008-10-01

    Full Text Available O objetivo deste estudo foi comparar amostras de efluente do Hospital São Vicente de Paulo com amostras de água do Rio Passo Fundo, quanto ao perfil de susceptibilidade de isolados de Pseudomonas aeruginosa, para inferir sobre a presença de isolados de origem hospitalar em amostras de água superficial. A significância estatística entre os perfis de susceptibilidade das amostras foi testada por análise de variância e a comparação das amostras foi feita por contrastes de interesse. Foram identificados 198 isolados de Pseudomonas aeruginosa a partir das amostras analisadas. O fenótipo de multirresistência não foi observado nas amostras do Rio Passo Fundo, embora alguns isolados resistentes a carbapenêmicos tenham sido identificados, indicando a presença de contaminação com bactérias provenientes de um ambiente sob forte pressão seletiva. Diferenças significativas entre as amostras de água e efluente hospitalar foram observadas a partir da análise de variância por contrastes de interesse.The aim of this study was to compare sewage samples from Hospital São Vicente de Paulo with water samples from the Passo Fundo river, with regard to the susceptibility profile of Pseudomonas aeruginosa isolates, in order to make inferences about the presence of strains of hospital origin in surface water samples. The statistical significance between the susceptibility profiles of the samples was tested using analysis of variance, and the samples were compared by means of contrasts of interest. One hundred and ninety-eight isolates of Pseudomonas aeruginosa were recovered from the samples analyzed. No phenotype for multiresistance was found in the samples from the Passo Fundo river, although some carbapenem-resistant isolates were identified, thereby indicating the presence of contamination with bacteria derived from an environment under strong selection pressure. Significant differences between the water and hospital effluent samples were

  10. Effects of Iron on DNA Release and Biofilm Development by Pseudomonas Aeruginosa

    DEFF Research Database (Denmark)

    Yang, Liang; Barken, Kim Bundvig; Skindersø, Mette Elena

    2007-01-01

    Extracellular DNA is one of the major matrix components in Pseudomonas aeruginosa biofilms. It functions as an intercellular connector and plays a role in stabilization of the biofilms. Evidence that DNA release in P. aeruginosa PAO1 biofilms is controlled by the las-rhl and pqs quorum-sensing sy......Extracellular DNA is one of the major matrix components in Pseudomonas aeruginosa biofilms. It functions as an intercellular connector and plays a role in stabilization of the biofilms. Evidence that DNA release in P. aeruginosa PAO1 biofilms is controlled by the las-rhl and pqs quorum......-sensing systems has been previously presented. This paper provides evidence that DNA release in P. aeruginosa PAO1 biofilms is also under iron regulation. Experiments involving cultivation of P. aeruginosa in microtitre trays suggested that pqs expression, DNA release and biofilm formation were favoured in media...

  11. The Freshwater Sponge Ephydatia fluviatilis Harbours Diverse Pseudomonas Species (Gammaproteobacteria, Pseudomonadales) with Broad-Spectrum Antimicrobial Activity

    Science.gov (United States)

    Keller-Costa, Tina; Jousset, Alexandre; van Overbeek, Leo; van Elsas, Jan Dirk; Costa, Rodrigo

    2014-01-01

    Bacteria are believed to play an important role in the fitness and biochemistry of sponges (Porifera). Pseudomonas species (Gammaproteobacteria, Pseudomonadales) are capable of colonizing a broad range of eukaryotic hosts, but knowledge of their diversity and function in freshwater invertebrates is rudimentary. We assessed the diversity, structure and antimicrobial activities of Pseudomonas spp. in the freshwater sponge Ephydatia fluviatilis. Polymerase Chain Reaction – Denaturing Gradient Gel Electrophoresis (PCR-DGGE) fingerprints of the global regulator gene gacA revealed distinct structures between sponge-associated and free-living Pseudomonas communities, unveiling previously unsuspected diversity of these assemblages in freshwater. Community structures varied across E. fluviatilis specimens, yet specific gacA phylotypes could be detected by PCR-DGGE in almost all sponge individuals sampled over two consecutive years. By means of whole-genome fingerprinting, 39 distinct genotypes were found within 90 fluorescent Pseudomonas isolates retrieved from E. fluviatilis. High frequency of in vitro antibacterial (49%), antiprotozoan (35%) and anti-oomycetal (32%) activities was found among these isolates, contrasting less-pronounced basidiomycetal (17%) and ascomycetal (8%) antagonism. Culture extracts of highly predation-resistant isolates rapidly caused complete immobility or lysis of cells of the protozoan Colpoda steinii. Isolates tentatively identified as P. jessenii, P. protegens and P. oryzihabitans showed conspicuous inhibitory traits and correspondence with dominant sponge-associated phylotypes registered by cultivation-independent analysis. Our findings suggest that E. fluviatilis hosts both transient and persistent Pseudomonas symbionts displaying antimicrobial activities of potential ecological and biotechnological value. PMID:24533086

  12. Biodegradation of Methyl tert-Butyl Ether by Co-Metabolism with a Pseudomonas sp. Strain

    Directory of Open Access Journals (Sweden)

    Shanshan Li

    2016-09-01

    Full Text Available Co-metabolic bioremediation is supposed to be an impressive and promising approach in the elimination technology of methyl tert-butyl ether (MTBE, which was found to be a common pollutant worldwide in the ground or underground water in recent years. In this paper, bacterial strain DZ13 (which can co-metabolically degrade MTBE was isolated and named as Pseudomonas sp. DZ13 based on the result of 16S rRNA gene sequencing analysis. Strain DZ13 could grow on n-alkanes (C5-C8, accompanied with the co-metabolic degradation of MTBE. Diverse n-alkanes with different carbon number showed a significant influence on the degradation rate of MTBE and accumulation of tert-butyl alcohol (TBA. When Pseudomonas sp. DZ13 co-metabolically degraded MTBE with n-pentane as the growth substrate, a higher MTBE-degrading rate (Vmax = 38.1 nmol/min/mgprotein, Ks = 6.8 mmol/L and lower TBA-accumulation was observed. In the continuous degradation experiment, the removal efficiency of MTBE by Pseudomonas sp. Strain DZ13 did not show an obvious decrease after five times of continuous addition.

  13. Pseudomonas alkylphenolica sp. nov., a bacterial species able to form special aerial structures when grown on p-cresol.

    Science.gov (United States)

    Mulet, Magdalena; Sánchez, David; Lalucat, Jorge; Lee, Kyoung; García-Valdés, Elena

    2015-11-01

    Pseudomonas sp. KL28T is an aerobic, rod-shaped bacterium that was isolated from the soil of Changwon, South Korea, based on its ability to grow in the presence of linear alkylphenols (C1-C5). Despite several studies on strain KL28T, it could not be assigned to any known species in the genus Pseudomonas. The name 'Pseudomonas alkylphenolia' was proposed for KL28T, but the strain had not until now been characterized taxonomically and the name currently has no standing in the bacterial nomenclature. A 16S rRNA gene sequence based phylogenetic analysis suggested an affiliation of strain KL28T with the Pseudomonas putida group, with Pseudomonas vranovensis DSM 16006T as the most closely related type strain (99.1 % similarity). A multilocus phylogenetic sequence analysis performed by concatenating 16S rRNA, gyrB, rpoD and rpoB partial gene sequences showed that isolate KL28T could be differentiated from P. vranovensis DSM 16006T (sequence similarity 93.7 %). Genomic comparisons of strain KL28T with the type strains of the species in the P. putida group using average nucleotide index based on blast (ANIb) and genome-to genome distances (GGDC) revealed 87.06 % and 32.20 % similarities with P. vranovensis DSM 16006T, respectively, as the closest type strain. Both values are far from the thresholds established for species differentiation. These results, together with differences in phenotypic features and chemotaxonomic analyses [fatty acids and whole-cell matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) MS], support the proposal of strain KL28T ( = JCM 16553T = KCTC 22206T) as the type strain of a novel species, for which the formerly proposed name, 'P. alkylphenolia', is correctly latinized as Pseudomonas alkylphenolica sp. nov.

  14. Identification of small molecule inhibitors of Pseudomonas aeruginosa exoenzyme S using a yeast phenotypic screen.

    Directory of Open Access Journals (Sweden)

    Anthony Arnoldo

    2008-02-01

    Full Text Available Pseudomonas aeruginosa is an opportunistic human pathogen that is a key factor in the mortality of cystic fibrosis patients, and infection represents an increased threat for human health worldwide. Because resistance of Pseudomonas aeruginosa to antibiotics is increasing, new inhibitors of pharmacologically validated targets of this bacterium are needed. Here we demonstrate that a cell-based yeast phenotypic assay, combined with a large-scale inhibitor screen, identified small molecule inhibitors that can suppress the toxicity caused by heterologous expression of selected Pseudomonas aeruginosa ORFs. We identified the first small molecule inhibitor of Exoenzyme S (ExoS, a toxin involved in Type III secretion. We show that this inhibitor, exosin, modulates ExoS ADP-ribosyltransferase activity in vitro, suggesting the inhibition is direct. Moreover, exosin and two of its analogues display a significant protective effect against Pseudomonas infection in vivo. Furthermore, because the assay was performed in yeast, we were able to demonstrate that several yeast homologues of the known human ExoS targets are likely ADP-ribosylated by the toxin. For example, using an in vitro enzymatic assay, we demonstrate that yeast Ras2p is directly modified by ExoS. Lastly, by surveying a collection of yeast deletion mutants, we identified Bmh1p, a yeast homologue of the human FAS, as an ExoS cofactor, revealing that portions of the bacterial toxin mode of action are conserved from yeast to human. Taken together, our integrated cell-based, chemical-genetic approach demonstrates that such screens can augment traditional drug screening approaches and facilitate the discovery of new compounds against a broad range of human pathogens.

  15. 40 CFR 180.1200 - Pseudomonas fluorescens strain PRA-25; temporary exemption from the requirement of a tolerance.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Pseudomonas fluorescens strain PRA-25... RESIDUES IN FOOD Exemptions From Tolerances § 180.1200 Pseudomonas fluorescens strain PRA-25; temporary... established for residues of the microbial pesticide, pseudomonas fluorescens strain PRA-25 when used on peas...

  16. Electrophoretic analysis of cyanide depletion by Pseudomonas alcaligenes.

    Science.gov (United States)

    Zaugg, S E; Davidson, R A; Walker, J C; Walker, E B

    1997-02-01

    Bacterial-facilitated depletion of cyanide is under development for remediation of heap leach operations in the gold mining industry. Capillary electrophoresis was found to be a powerful tool for quantifying cyanide depletion. Changes in cyanide concentration in aqueous suspensions of Pseudomonas alcaligenes bacteria and cyanide at elevated pH were easily monitored by capillary electrophoresis. The resulting data can be used to study rates of cyanide depletion by this strain of bacteria. Concentrations of these bacteria at 10(5) cells/mL were found to reduce cyanide from 100 ppm to less than 8 ppm in four days. In addition, other ions of interest in cyanide metabolism, such as formate, can be simultaneously analyzed. Direct UV detection of cyanide at 192 nm further simplifies the analytical method for these ions.

  17. Pseudomonas endophytica sp. nov., isolated from stem tissue of Solanum tuberosum L. in Spain.

    Science.gov (United States)

    Ramírez-Bahena, Martha-Helena; Cuesta, Maria José; Tejedor, Carmen; Igual, José Mariano; Fernández-Pascual, Mercedes; Peix, Álvaro

    2015-07-01

    A bacterial strain named BSTT44(T) was isolated in the course of a study of endophytic bacteria occurring in stems and roots of potato growing in a soil from Salamanca, Spain. The 16S rRNA gene sequence had 99.7% identity with respect to that of its closest relative, Pseudomonas psychrophila E-3T, and the next most closely related type strains were those of Pseudomonas fragi, with 99.6% similarity, Pseudomonas deceptionensis, with 99.2% similarity, and Pseudomonas lundensis, with 99.0% similarity; these results indicate that BSTT44(T) should be classified within the genus Pseudomonas. Analysis of the housekeeping genes rpoB, rpoD and gyrB confirmed its phylogenetic affiliation and showed identities lower than 92% in all cases with respect to the above-mentioned closest relatives. Cells of the strain bore one polar-subpolar flagellum. The respiratory quinone was Q-9.The major fatty acids were C16:0, C18:1ω7c and summed feature 3 (C16:1ω7c and/or C16:1ω6c). The strain was oxidase-, catalase- and urease-positive and the arginine dihydrolase system was present, but tests for nitrate reduction, β-galactosidase production and aesculin hydrolysis were negative. It could grow at 35 °C and at pH 5-9.The DNA G+C content was 60.2 mol%. DNA-DNA hybridization results showed less than 48% relatedness with respect to the type strains of the four most closely related species. Therefore, the combined results of genotypic, phenotypic and chemotaxonomic analyses support the classification of strain BSTT44 into a novel species of the genus Pseudomonas, for which the name Pseudomonas endophytica sp. nov. is proposed. The type strain is BSTT44(T) ( = LMG 28456(T) = CECT 8691(T)).

  18. SANITATION PROCESS OPTIMALIZATION IN RELATION TO THE MICROBIAL BIOFILM OF PSEUDOMONAS FLUORESCENS

    Directory of Open Access Journals (Sweden)

    Vladimír Vietoris

    2012-02-01

    Full Text Available Biofilms have been of considerable interest in the context of food hygiene. Extracellular polymeric substances play an important role in the attachment and colonization of microorganisms to food-contact surfaces. If the microorganisms from food-contact surfaces are not completely removed, they may lead to biofilm formation and also increase the biotransfer potential. The experimental part was focused on the adhesion of bacterial cells under static conditions and testing the effectiveness of disinfectants on created biofilm. In laboratory conditions we prepared and formed the bacterial biofilms Pseudomonas fluorescens in the test surfaces of stainless steel. Over the 72 hours and the next 72 hours were observed numbers of adhesion bacterial cells of Pseudomonas fluorescens on solid surfaces of tested materials.

  19. Pseudo-outbreak of pseudomonas aeruginosa in HIV-infected patients undergoing fiberoptic bronchoscopy

    DEFF Research Database (Denmark)

    Kolmos, H J; Lerche, A; Kristoffersen, Kirsten Lydia

    1994-01-01

    Pseudomonas aeruginosa was isolated from bronchoalveolar lavage fluid from 8 consecutive patients undergoing bronchoscopy at an infectious diseases unit. None of the patients developed signs of respiratory tract infection that could be ascribed to the organism. The source of contamination...

  20. Top 10 plant pathogenic bacteria in molecular plant pathology.

    Science.gov (United States)

    Mansfield, John; Genin, Stephane; Magori, Shimpei; Citovsky, Vitaly; Sriariyanum, Malinee; Ronald, Pamela; Dow, Max; Verdier, Valérie; Beer, Steven V; Machado, Marcos A; Toth, Ian; Salmond, George; Foster, Gary D

    2012-08-01

    Many plant bacteriologists, if not all, feel that their particular microbe should appear in any list of the most important bacterial plant pathogens. However, to our knowledge, no such list exists. The aim of this review was to survey all bacterial pathologists with an association with the journal Molecular Plant Pathology and ask them to nominate the bacterial pathogens they would place in a 'Top 10' based on scientific/economic importance. The survey generated 458 votes from the international community, and allowed the construction of a Top 10 bacterial plant pathogen list. The list includes, in rank order: (1) Pseudomonas syringae pathovars; (2) Ralstonia solanacearum; (3) Agrobacterium tumefaciens; (4) Xanthomonas oryzae pv. oryzae; (5) Xanthomonas campestris pathovars; (6) Xanthomonas axonopodis pathovars; (7) Erwinia amylovora; (8) Xylella fastidiosa; (9) Dickeya (dadantii and solani); (10) Pectobacterium carotovorum (and Pectobacterium atrosepticum). Bacteria garnering honourable mentions for just missing out on the Top 10 include Clavibacter michiganensis (michiganensis and sepedonicus), Pseudomonas savastanoi and Candidatus Liberibacter asiaticus. This review article presents a short section on each bacterium in the Top 10 list and its importance, with the intention of initiating discussion and debate amongst the plant bacteriology community, as well as laying down a benchmark. It will be interesting to see, in future years, how perceptions change and which bacterial pathogens enter and leave the Top 10. © 2012 The Authors. Molecular Plant Pathology © 2012 BSPP and Blackwell Publishing Ltd.

  1. Equilibrium, thermodynamic and kinetic studies on biosorption of Mn(II) from aqueous solution by Pseudomonas sp., Staphylococcus xylosus and Blakeslea trispora cells

    International Nuclear Information System (INIS)

    Gialamouidis, D.; Mitrakas, M.; Liakopoulou-Kyriakides, M.

    2010-01-01

    Biosorption of Mn(II) from aqueous solutions using Pseudomonas sp., Staphylococcus xylosus and Blakeslea trispora cells was investigated under various experimental conditions of pH, biomass concentration, contact time and temperature. The optimum pH value was determined to 6.0 and the optimum biomass concentration to 1.0 g L -1 for all types of cells. Mn(II) biosorption was found to fit better to the Langmuir model for Pseudomonas sp. and B. trispora and to Freundlich model for S. xylosus. Langmuir model gave maximum Mn(II) uptake capacity 109 mg g -1 for Pseudomonas sp. and much lower, 59 mg g -1 and 40 mg g -1 for S. xylosus and B. trispora, respectively. Pseudo-second-order kinetic model was also found to be in good agreement with the experimental results. Thermodynamic parameters of the adsorption confirmed the endothermic nature of sorption process with positive heat of enthalpy, accompanied by a positive value of entropy change. Interestingly, desorption experiments by treating biomass with 0.1 M HNO 3 solution resulted to more than 88% recovery of the adsorbed Mn(II) from Pseudomonas sp. and almost 95% and 99% from S. xylosus and B. trispora cells respectively, thus indicating that Mn(II) can be easily and quantitatively recovered from biomass.

  2. Detection of metallo-beta-lactamase producing Pseudomonas ...

    African Journals Online (AJOL)

    sunny t

    2016-02-24

    Feb 24, 2016 ... Since the increasing prevalence of carbapenem-resistant Pseudomonas aeruginosa spp., accurate detection of metallo-β-lactamase (MBL) such as blaVIM type enzyme producing isolates became very important. However, phenotypic MBL detection methods previously reported are not highly sensitive or.

  3. Elongation factor P is dispensable in Escherichia coli and Pseudomonas aeruginosa.

    Science.gov (United States)

    Balibar, Carl J; Iwanowicz, Dorothy; Dean, Charles R

    2013-09-01

    Elongation factor P (EF-P) is a highly conserved ribosomal initiation factor responsible for stimulating formation of the first peptide bond. Its essentiality has been debated and may differ depending on the organism. Here, we demonstrate that EF-P is dispensable in Escherichia coli and Pseudomonas aeruginosa under laboratory growth conditions. Although knockouts are viable, growth rates are diminished compared with wild-type strains. Despite this cost in fitness, these mutants are not more susceptible to a wide range of antibiotics; including ribosome targeting antibiotics, such as lincomycin, chloramphenicol, and streptomycin, which have been shown previously to disrupt EF-P function in vitro. In Pseudomonas, knockout of efp leads to an upregulation of mexX, a phenotype previously observed with other genetic lesions affecting ribosome function and that can be induced by the treatment with antibiotics affecting protein synthesis.

  4. The impact of nosocomially-acquired resistant Pseudomonas aeruginosa infection in a burn unit.

    Science.gov (United States)

    Armour, Alexis D; Shankowsky, Heather A; Swanson, Todd; Lee, Jonathan; Tredget, Edward E

    2007-07-01

    Nosocomially-acquired Pseudomonas aeruginosa remains a serious cause of infection and septic mortality in burn patients. This study was conducted to quantify the impact of nosocomially-transmitted resistant P. aeruginosa in a burn population. Using a TRACS burn database, 48 patients with P. aeruginosa resistant to gentamicin were identified (Pseudomonas group). Thirty-nine were case-matched to controls without resistant P. aeruginosa cultures (control group) for age, total body surface area, admission year, and presence of inhalation injury. Mortality and various morbidity endpoints were examined, as well as antibiotic costs. There was a significantly higher mortality rate in the Pseudomonas group (33% vs. 8%, p products used (packed cells 51.1 +/- 8.0 vs. 21.1 +/- 3.4, p < 0.01; platelets 11.9 +/- 3.0 vs. 1.4 +/- 0.7, p < 0.01) were all significantly higher in the Pseudomonas group. Cost of antibiotics was also significantly higher ($2,658.52 +/- $647.93 vs. $829.22 +/- $152.82, p < 0.01). Nosocomial colonization or infection, or both, of burn patients with aminoglycoside-resistant P. aeruginosa is associated with significantly higher morbidity, mortality, and cost of care. Increased resource consumption did not prevent significantly higher mortality rates when compared with that of control patients. Thus, prevention, identification, and eradication of nosocomial Pseudomonas contamination are critical for cost-effective, successful burn care.

  5. 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

    Recent reports have shown that several strains of Pseudomonas putida produce N-acylhomoserine lactones (AHLs). These signal molecules enable bacteria to coordinately express certain phenotypic traits in a density-dependent manner in a process referred to as quorum sensing. In this study we have...

  6. Identification of novel transaminases from a 12-aminododecanoic acid-metabolizing Pseudomonas strain.

    Science.gov (United States)

    Wilding, Matthew; Walsh, Ellen F A; Dorrian, Susan J; Scott, Colin

    2015-07-01

    A Pseudomonas species [Pseudomonas sp. strain amino alkanoate catabolism (AAC)] was identified that has the capacity to use 12-aminododecanoic acid, the constituent building block of homo-nylon-12, as a sole nitrogen source. Growth of Pseudomonas sp. strain AAC could also be supported using a range of additional ω-amino alkanoates. This metabolic function was shown to be most probably dependent upon one or more transaminases (TAs). Fourteen genes encoding putative TAs were identified from the genome of Pseudomonas sp. AAC. Each of the 14 genes was cloned, 11 of which were successfully expressed in Escherichia coli and tested for activity against 12-aminododecanoic acid. In addition, physiological functions were proposed for 9 of the 14 TAs. Of the 14 proteins, activity was demonstrated in 9, and of note, 3 TAs were shown to be able to catalyse the transfer of the ω-amine from 12-aminododecanoic acid to pyruvate. Based on this study, three enzymes have been identified that are promising biocatalysts for the production of nylon and related polymers. © 2015 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.

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

    African Journals Online (AJOL)

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

  8. Antimicrobial effect of Al2O3, Ag and Al2O3/Ag thin films on Escherichia coli and Pseudomonas putida

    International Nuclear Information System (INIS)

    Angelov, O; Stoyanova, D; Ivanova, I; Todorova, S

    2016-01-01

    The influence of Al 2 O 3 , Ag and Al 2 O 3 /Ag thin films on bacterial growth of Gramnegative bacteria Pseudomonas putida and Escherichia coli is studied. The nanostructured thin films are deposited on glass substrates without intentional heating through r.f. magnetron sputtering in Ar atmosphere of Al 2 O 3 and Ag targets or through sequential sputtering of Al 2 O 3 and Ag targets, respectively. The individual Ag thin films (thickness 8 nm) have a weak bacteriostatic effect on Escherichia coli expressed as an extended adaptive phase of the bacteria up to 5 hours from the beginning of the experiment, but the final effect is only 10 times lower bacterial density than in the control. The individual Al 2 O 3 film (20 nm) has no antibacterial effect against two strains E. coli - industrial and pathogenic. The Al 2 O 3 /Ag bilayer films (Al 2 O 3 20 nm/Ag 8 nm) have strong bactericidal effect on Pseudomonas putida and demonstrate an effective time of disinfection for 2 hours. The individual films Al2O3 and Ag have not pronounced antibacterial effect on Pseudomonas putida . A synergistic effect of Al2O3/Ag bilayer films in formation of oxidative species on the surface in contact with the bacterial suspension could be a reason for their antimicrobial effect on E. coli and P. putida . (paper)

  9. Mechanisms involved in the evasion of the host defence by Pseudomonas aeruginosa

    DEFF Research Database (Denmark)

    Kharazmi, A

    1991-01-01

    Pseudomonas aeruginosa, an extracellular opportunistic pathogen, utilizes two major mechanisms to evade the host defence system. One of these mechanisms is the production of a large number of extracellular products, such as proteases, toxins, and lipases. The two proteases, alkaline protease and ...

  10. Pseudomonas aeruginosa biofilm formation and slime excretion on antibiotic-loaded bone cement

    NARCIS (Netherlands)

    Neut, D; Hendriks, JGE; van Horn, Jim R.; van der Mei, HC; Busscher, HJ

    Background Infection is an infrequent but serious complication of prosthetic joint surgery. These infections will usually not clear until the implant is removed and re-implantation has a high failure rate, especially when Pseudomonas aeruginosa is involved. Material and methods We examined

  11. 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.

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

    Science.gov (United States)

    Marinho, Palloma Rodrigues; Moreira, Ana Paula Barbosa; Pellegrino, Flávia Lúcia Piffano Costa; Muricy, Guilherme; Bastos, Maria do Carmo de Freire; Santos, Kátia Regina Netto dos; Giambiagi-deMarval, Marcia; Laport, Marinella Silva

    2009-08-01

    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.

  13. Mercury affects the distribution of culturable species of Pseudomonas in soil

    DEFF Research Database (Denmark)

    Holtze, Maria Sommer; Nielsen, Preben; Ekelund, Flemming

    2006-01-01

    Pseudomonas bacteria isolated during 52 days on Gould's S1 agar from soil spiked with 0, 3.5 and 15 mg Hg(II) kg soil(-1) were characterised to reveal whether mercury affected them differently. Isolates from the treatments with 0 and 15 mg Hg kg(-1) were characterised using FT-IR characterisation...... was almost exclusively restricted to P. frederiksbergensis and P. migulae groups. We conclude that Hg caused a shift in the dominating species of culturable Pseudomonas....

  14. Antibiotic Sensitivity in Pseudomonas aeruginosa of Diabetic Patient’s Foot Ulcer

    OpenAIRE

    Pratiwi Apridamayanti; Khairunnisa Azani Meilinasary; Rafika Sari

    2016-01-01

    Diabetes Mellitus (DM) patients are at risk to have the diabetic ulcer. The main reason for DM’s patient with ulcer complication to be treated and healed in hospital is bacterial infection. One of many bacteria that infects diabetic ulcer is Pseudomonas aeruginosa. This conditian can be treated by antibiotic. The using antibiotic is often inaccurate causing the microbe resistance. To choose the right antibiotic, it needs to test the antibiotic’s sensitivity towards Pseudomonas aeruginosa. The...

  15. Comparison of 432 Pseudomonas strains through integration of genomic, functional, metabolic and expression data

    NARCIS (Netherlands)

    Koehorst, Jasper J.; Dam, van Jesse C.J.; Heck, van Ruben G.A.; Saccenti, Edoardo; Martins dos Santos, Vitor; Suarez-Diez, Maria; Schaap, Peter J.

    2016-01-01

    Pseudomonas is a highly versatile genus containing species that can be harmful to humans and plants while others are widely used for bioengineering and bioremediation. We analysed 432 sequenced Pseudomonas strains by integrating results from a large scale functional comparison using protein

  16. Sensitivity patterns of pseudomonas aeruginosa isolates obtained from clinical specimens in peshawar

    International Nuclear Information System (INIS)

    Abbas, S.H.; Khan, M.Z.U.; Naeem, M.

    2015-01-01

    Pseudomonas aeruginosa (P. aeruginosa) is a highly virulent opportunistic pathogen and a leading cause of nosocomial infections.Affected patients are often hospitalized in an intensive care unit, and are immuno-compromised as a result of disease and treatment. Suspected P. aeruginosa require timely, adequate and empirical antibiotic therapy to ensure improved outcomes. The purpose of the study was to find the sensitivity and resistance pattern of P. aeruginosa to various groups of drugs, in clinical isolates collected from two major tertiary care hospitals of Peshawar. Methods: Different clinical isolate were taken from patients admitted in various wards of Khyber Teaching Hospital and Lady Reading Hospital Peshawar. Results: A total of 258 clinical isolates were positive for P. aeruginosa out of 2058 clinical isolates. Pseudomonas showed high degree of resistance to third generation Cephalosporins (Ceftazidime, and Ceftriaxone) and moderate degree of resistance to Quinolones and Aminoglycosides (Ofloxacin, Ciprofloxacin, Levofloxacin and Amikacin). Low resistance was observed to different combinations (Cefoperazone + Sulbactum, Piperacillin + Tazobactum). Meropenem and Imipenem had negligible resistance. Conclusion: There is growing resistance to different classes of antibiotics. Combination drugs are useful approach for empirical treatment in suspected Pseudomonas infection. Imipenem and Meropenem are extremely effective but should be in reserve. (author)

  17. Three Strains of Pseudomonas fluorescens Exhibit Differential Toxicity Against Drosophila melanogaster

    Science.gov (United States)

    Three strains of Pseudomonas fluorescens were tested for toxicity to Drosophila melanogaster in an insect feeding assay. Insect eggs were placed on the surface of a non-nutritive agar plate supplemented with a food source that was non-inoculated or inoculated with P. fluorescens Pf0-1, SBW25, or Pf-...

  18. Regulatory T cell activity in immunosuppresive mice model of pseudomonas aeruginosa pneumonia.

    Science.gov (United States)

    Li, Jun-Lu; Chen, Ting-Sang; Yuan, Cong-Cong; Zhao, Guo-Qiang; Xu, Min; Li, Xiao-Yan; Cao, Jie; Xing, Li-Hua

    2017-08-01

    Pseudomonas aeruginosa (PA) pneumonia is a refractory, even lethal complication in immunosuppressive individuals and immune disturbances may promote the pathological process. We aimed to investigate the regulatory T (Treg) cell activity in an immunosuppressive mice model of PA pneumonia by estimating levels of main transcription factor and the main effector of Treg cells, i.e., Forkhead box protein 3 (FOXP3) and interleukine-10 (IL-10). Seventy-two BALB/c mice were divided into four groups randomly: control (A), PA pneumonia (B), immunosuppression (C) and immunosuppression with PA pneumonia (D). Mice were sacrificed at 4, 8 and 24 h after establishing experimental models. The pathological changes of lung tissue were graded, and the FOXP3 mRNA and serum IL-10 levels were detected. Histological analysis of lung tissues showed there were no significantly pathological changes in groups A and C, but significantly pathological changes were found in groups B and D, especially in group D at 8 h (Ppneumonia in immunosuppressive individuals worsens rapidly, which may be associated with Treg cells function disturbance. And Treg cells may be promising as adjuvant therapeutics for PA pneumonia in immunosuppressive individuals.

  19. Long-Chain 4-Aminoquinolines as Quorum Sensing Inhibitors in Serratia marcescens and Pseudomonas aeruginosa.

    Science.gov (United States)

    Aleksić, Ivana; Šegan, Sandra; Andrić, Filip; Zlatović, Mario; Moric, Ivana; Opsenica, Dejan M; Senerovic, Lidija

    2017-05-19

    Antibiotic resistance has become a serious global threat to public health; therefore, improved strategies and structurally novel antimicrobials are urgently needed to combat infectious diseases. Here we report a new type of highly potent 4-aminoquinoline derivatives as quorum sensing inhibitors in Serratia marcescens and Pseudomonas aeruginosa, exhibiting weak bactericidal activities (minimum inhibitory concentration (MIC) > 400 μM). Through detailed structure-activity study, we have identified 7-Cl and 7-CF 3 substituted N-dodecylamino-4-aminoquinolines (5 and 10) as biofilm formation inhibitors with 50% biofilm inhibition at 69 μM and 63 μM in S. marcescens and P. aeruginosa, respectively. These two compounds, 5 and 10, are the first quinoline derivatives with anti-biofilm formation activity reported in S. marcescens. Quantitative structure-activity relationship (QSAR) analysis identified structural descriptors such as Wiener indices, hyper-distance-path index (HDPI), mean topological charge (MTC), topological charge index (TCI), and log D(o/w) exp as the most influential in biofilm inhibition in this bacterial species. Derivative 10 is one of the most potent quinoline type inhibitors of pyocyanin production described so far (IC 50 = 2.5 μM). While we have demonstrated that 5 and 10 act as Pseudomonas quinolone system (PQS) antagonists, the mechanism of inhibition of S. marcescens biofilm formation with these compounds remains open since signaling similar to P. aeruginosa PQS system has not yet been described in Serratia and activity of these compounds on acylhomoserine lactone (AHL) signaling has not been detected. Our data show that 7-Cl and 7-CF 3 substituted N-dodecylamino-4-aminoquinolines present the promising scaffolds for developing antivirulence and anti-biofilm formation agents against multidrug-resistant bacterial species.

  20. Enhanced alpha-galactosidase expression in pseudomonas chlororaphis

    Science.gov (United States)

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

  1. Multiple Pseudomonas species secrete exolysin-like toxins and provoke Caspase-1-dependent macrophage death.

    Science.gov (United States)

    Basso, Pauline; Wallet, Pierre; Elsen, Sylvie; Soleilhac, Emmanuelle; Henry, Thomas; Faudry, Eric; Attrée, Ina

    2017-10-01

    Pathogenic bacteria secrete protein toxins that provoke apoptosis or necrosis of eukaryotic cells. Here, we developed a live-imaging method, based on incorporation of a DNA-intercalating dye into membrane-damaged host cells, to study the kinetics of primary bone marrow-derived macrophages (BMDMs) mortality induced by opportunistic pathogen Pseudomonas aeruginosa expressing either Type III Secretion System (T3SS) toxins or the pore-forming toxin, Exolysin (ExlA). We found that ExlA promotes the activation of Caspase-1 and maturation of interleukin-1β. BMDMs deficient for Caspase-1 and Caspase-11 were resistant to ExlA-induced death. Furthermore, by using KO BMDMs, we determined that the upstream NLRP3/ASC complex leads to the Caspase-1 activation. We also demonstrated that Pseudomonas putida and Pseudomonas protegens and the Drosophila pathogen Pseudomonas entomophila, which naturally express ExlA-like toxins, are cytotoxic toward macrophages and provoke the same type of pro-inflammatory death as does ExlA + P. aeruginosa. These results demonstrate that ExlA-like toxins of two-partner secretion systems from diverse Pseudomonas species activate the NLRP3 inflammasome and provoke inflammatory pyroptotic death of macrophages. © 2017 Society for Applied Microbiology and John Wiley & Sons Ltd.

  2. Daya Tahan Hidup Pseudomonas putida Strain Pf-20 dalam Beberapa Macam Inokulum

    Directory of Open Access Journals (Sweden)

    Yenny Wuryandari

    2004-07-01

    Full Text Available For any crop-protection agent, an efficient formulation is a necessity to translate laboratory activity into adequate field performance. There are particular challenges to be faced in formulation of biological control agents, because the active ingredient is a living organism that must be kept relatively immobile and inactive while in storage, but quickly resume its  normal metabolic processes once applied to the target site. The objective of the research was  to study survival of Pseudomonas putida strain Pf-20 in various formulations at the storage  time and germination. The twelve formulations include carriers, additives and concentration  of Pf-20. The efficacy of various formulation in maintaining the population of Pf-20 in storage was assessed. The research result showed that population of Pf 20  in the formulation  number seven was the highest, with the combination peat+talc, CMC+arginin and  concentration of Pf[20 10^10 CFU/ml. In peat+talc, CMC+arginin, Pf-20 10^10  CFU/ml based formulation the bacteria survived even up to 84 days of storage although the population declined. In all formulations, population of Pf-20 increased at the time of seed germination. At the time of seed germination, formulation number seven was the highest too.

  3. CLONING AND SEQUENCING OF PSEUDOMONAS GENES DETERMINING SODIUM DODECYL-SULFATE BIODEGRADATION

    NARCIS (Netherlands)

    DAVISON, J; BRUNEL, F; PHANOPOULOS, A; PROZZI, D; TERPSTRA, P

    1992-01-01

    The nucleotide sequences of two genes involved in sodium dodecyl sulfate (SDS) degradation, by Pseudomonas, have been determined. One of these, sdsA, codes for an alkyl sulfatase (58 957 Da) and has similarity (31.8% identity over a 201-amino acid stretch) to the N terminus of a predicted protein of

  4. UVC fluencies for preventative treatment of Pseudomonas aeruginosa contaminated polymer tubes

    DEFF Research Database (Denmark)

    Bak, Jimmy; Ladefoged, Søren D; Begovic, Tanja

    2010-01-01

    Exposing Pseudomonas aeruginosa biofilm grown on the inner surface of Teflon and silicone tubes to UVC light (265 nm) from light emitting diodes (LED) has previously been shown to substantially reduce biofilm growth. Smaller UVC fluencies were required to disinfect Teflon tubes compared to silicone...... tubes. Light propagation enhancement in tubes can be obtained if the refractive index of the intra-luminal saline solution is higher than that of the polymer. This condition is achieved by using Teflon tubes with a low refractive index (1.34) instead of the polymers with a high refractive index (1...... is demonstrated to be a preventative disinfection treatment on tubes made of Teflon, which enhances the UVC light propagation, and on tubes made of a softer material, ethylene vinyl acetate (EVA), which is suitable for catheters but much less suitable for UVC light propagation. Simulating an aseptic breach (~10...

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

    African Journals Online (AJOL)

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

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

    African Journals Online (AJOL)

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

  7. Extracytoplasmic function sigma factors in Pseudomonas syringae

    DEFF Research Database (Denmark)

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

    2005-01-01

    Genome analyses of the plant pathogens Pseudomonas syringae pv. tomato DC3000, pv. syringae B728a and pv. phaseolicola 1448A reveal fewer extracytoplasmic function (ECF) sigma factors than in related Pseudomonads with different lifestyles. We highlight the presence of a P. syringae-specific ECF...

  8. Enriquecimiento diferencial de Pseudomonas spp. en el rizoplano de distintas especies cultivadas

    Directory of Open Access Journals (Sweden)

    Mariana A Marrero

    2015-06-01

    Full Text Available En contraste con la simbiosis entre rizobios y leguminosas, la especificidad de las Pseudomonas en la colonización radicular parece menos estricta. Sin embargo, estudios sobre la diversidad bacteriana del nicho rizosférico resaltan la influencia de la especie vegetal en la selección específica de ciertos microorganismos a partir de la flora residente del suelo. Para evaluar el efecto que los cultivos extensivos de nuestro país tienen sobre la estructura de las comunidades de Pseudomonas, se realizaron experimentos con plantas trampa, partiendo de semillas de trigo, maíz y soja desinfectadas superficialmente y sembradas en un mismo suelo prístino. A partir de las suspensiones representativas de la microflora del rizoplano, se realizaron recuentos en placa en medio selectivo para Pseudomonas. El conjunto de colonias originado a partir de los distintos rizoplanos se utilizó como fuente de ADN para analizar la estructura de comunidad a través del perfil de restricción de amplicones de los genes oprF y gacA. El análisis comparativo de estos perfiles agrupó a las muestras por especie de planta y las distinguió del patrón obtenido a partir del suelo prístino. La secuenciación parcial del gen 16S ADNr de aislamientos bacterianos representativos confirmó la existencia de genotipos enriquecidos diferencialmente en el rizoplano de cada especie vegetal. Estos resultados apoyan la hipótesis de la existencia de mecanismos de selección específica de estirpes de Pseudomonas a partir de la flora nativa del suelo en la interacción cooperativa entre estas PGPR y las raíces de diferentes cultivos como trigo, soja y maíz.

  9. Physiological and biochemical characterization of a novel nicotine-degrading bacterium Pseudomonas geniculata N1.

    Directory of Open Access Journals (Sweden)

    Yanghui Liu

    Full Text Available Management of solid wastes with high nicotine content, such as those accumulated during tobacco manufacturing, poses a major challenge, which can be addressed by using bacteria such as Pseudomonas and Arthrobacter. In this study, a new species of Pseudomonas geniculata, namely strain N1, which is capable of efficiently degrading nicotine, was isolated and identified. The optimal growth conditions for strain N1 are a temperature of 30°C, and a pH 6.5, at a rotation rate of 120 rpm min(-1 with 1 g l(-1 nicotine as the sole source of carbon and nitrogen. Myosmine, cotinine, 6-hydroxynicotine, 6-hydroxy-N-methylmyosmine, and 6-hydroxy-pseudooxynicotine were detected as the five intermediates through gas chromatography-mass and liquid chromatography-mass analyses. The identified metabolites were different from those generated by Pseudomonas putida strains. The analysis also highlighted the bacterial metabolic diversity in relation to nicotine degradation by different Pseudomonas strains.

  10. The high-affinity peptidoglycan binding domain of Pseudomonas phage endolysin KZ144

    Energy Technology Data Exchange (ETDEWEB)

    Briers, Yves [Division of Gene Technology, Department of Biosystems, Katholieke Universiteit Leuven, Kasteelpark Arenberg 21, B-3001 Leuven (Belgium); Schmelcher, Mathias; Loessner, Martin J. [Institute of Food Science and Nutrition, ETH Zuerich, Schmelzbergstrasse 7, CH-8092 Zuerich (Switzerland); Hendrix, Jelle; Engelborghs, Yves [Laboratory of Biomolecular Dynamics, Department of Chemistry, Katholieke Universiteit Leuven, Celestijnenlaan 200G, B-3001 Leuven (Belgium); Volckaert, Guido [Division of Gene Technology, Department of Biosystems, Katholieke Universiteit Leuven, Kasteelpark Arenberg 21, B-3001 Leuven (Belgium); Lavigne, Rob, E-mail: rob.lavigne@biw.kuleuven.be [Division of Gene Technology, Department of Biosystems, Katholieke Universiteit Leuven, Kasteelpark Arenberg 21, B-3001 Leuven (Belgium)

    2009-05-29

    The binding affinity of the N-terminal peptidoglycan binding domain of endolysin KZ144 (PBD{sub KZ}), originating from Pseudomonas aeruginosa bacteriophage {phi}KZ, has been examined using a fusion protein of PBD{sub KZ} and green fluorescent protein (PBD{sub KZ}-GFP). A fluorescence recovery after photobleaching analysis of bound PBD{sub KZ}-GFP molecules showed less than 10% fluorescence recovery in the bleached area within 15 min. Surface plasmon resonance analysis confirmed this apparent high binding affinity revealing an equilibrium affinity constant of 2.95 x 10{sup 7} M{sup -1} for the PBD{sub KZ}-peptidoglycan interaction. This unique domain, which binds to the peptidoglycan of all tested Gram-negative species, was harnessed to improve the specific activity of the peptidoglycan hydrolase domain KMV36C. The chimeric peptidoglycan hydrolase (PBD{sub KZ}-KMV36C) exhibits a threefold higher specific activity than the native catalytic domain (KMV36C). These results demonstrate that the modular assembly of functional domains is a rational approach to improve the specific activity of endolysins from phages infecting Gram-negatives.

  11. Bioligand-mediated partitioning of radionuclides to the aqueous phase

    International Nuclear Information System (INIS)

    Johnsson, A.; Pedersen, K.; Oedegaard-Jensen, A.; Jakobsson, A.M.; Ekberg, C.

    2008-01-01

    The aqueous-phase partitioning of 59 Fe, 147 Pm, 234 Th and 241 Am by complexing compounds from subsurface bacteria has previously been studied in the presence of quartz sand. In this study the aqueous-phase partitioning of pico- to submicromolar amounts of 59 Fe, 147 Pm, 234 Th and 241 Am was analyzed in the presence of TiO 2 and exudates from three species of subsurface bacteria: Pseudomonas fluorescens, Pseudomonas stutzeri, and Shewanella putrefaciens. All were grown under aerobic conditions and P. stutzeri and S. putrefaciens were grown under anaerobic conditions as well. The supernatants of the aerobic and anaerobic cultures were collected and radionuclide was added. TiO 2 , with BET surface area of 49.9 m 2 x g -1 , was added to the supernatant radionuclide mix, and the pH was adjusted to approximately 8. After incubation, the amount of radionuclide in the liquid phase of the samples and controls was analyzed using scintillation method. Two types of values were calculated: solution% = the activity maintained in solution relative to the total activity, and Q-values = the quotient between the activity in samples and the activity in controls. Aerobic supernatants had solution% values between 89% and 100% for 59 Fe and between 18 and 43% for 234 Th. The solution% values for 241 Am and 147 Pm were less than 2% overall, but the Q-values were between 34 and 115 times more 241 Am in bacterial supernatants than in controls. The corresponding values for 147 Pm ranged from 6 to 20 times more than in the control. The solution% values for all elements in the presence of anaerobic supernatants were below 2%, but the Q-values clustered around 7 for 59 Fe and ranging from 2 to 29 for 234 Th, indicated that anaerobic supernatants partitioned these elements to the aqueous phase. Both aerobic and anaerobic supernatants tested positive for complexing compounds when analyzed, using the Chrome Azurol S assay. Complexation with excreted organic ligands is most likely the reason

  12. Isolasi Dan Identifikasi Pseudomonas Dari Tanah Kebun Biologi Wamena Dan Uji Awal Sebagai Agen Biokontrol Fusarium*[the Isolation and Identification of Pseudomonas From the Wamena Biological Gardens Soil and Its Preliminary Test as Biocontrol Agent on Fusari

    OpenAIRE

    Latupapua, HJD; Nurhidayat, N

    2003-01-01

    Pseudomonas bacteria plays essential role in soil ecology such as decomposer and biological control. The bacteria were isolated on selective media and identified from five soil samples taken within area of Wamena Biological Gardens.There are six species Pseudomonas were indentified based on morphological characters and biochemical reaction.P. striata was found to be common in soil of the area.No pathogen Pseudomonas was indentified in all soil samples. Preliminary study on biological control ...

  13. Detection of extended spectrum β-lactamase in Pseudomonas spp. isolated from two tertiary care hospitals in Bangladesh

    Directory of Open Access Journals (Sweden)

    Begum Shahanara

    2013-01-01

    Full Text Available Abstract Background Extended spectrum ß-lactamases (ESBLs represent a major group of lactamases responsible for resistance, mostly produced by gram-negative bacteria, to newer generations of ß-lactam drugs currently being identified in large numbers worldwide. The present study was undertaken to see the frequency of ESBL producing Pseudomonas spp. isolated from six hundred clinical specimens (wound, pus, aural, urine, sputum, throat and other swabs collected over a period of three years from two tertiary care hospitals in Bangladesh. Findings Aerobic bacterial culture was performed on aseptically collected swabs and only growth of Pseudomonas was considered for further species identification and ESBL production along with serotyping of Pseudomonas aeruginosa. Antimicrobial susceptibility testing was carried out using the Kirby-Bauer agar diffusion method and ESBL production was detected on Mueller Hinton agar by double-disk synergy technique using Amoxicillin-Clavulanic acid with Ceftazidime, Cefotaxime, Ceftriaxone and Aztreonam. Culture yielded 120 Pseudomonas spp. and 82 of them were biochemically characterized for species. Pseudomonas aeruginosa was found to be the predominant (90.2% species. Of 82 isolates tested for ESBL, 31 (37.8% were ESBL positive with 29 (93.5% as Pseudomonas aeruginosa, the remaining 2 (6.5% were Stenotrophomonas maltophilia and Ralstonia pickettii. Antibiogram revealed Imipenem as the most effective drug (93.3% among all antimicrobials used against Pseudomonas spp. followed by Aminoglycosides (63.7%. Conclusion ESBL producing Pseudomonas spp. was found to be a frequent isolate from two tertiary care hospitals in Bangladesh, showing limited susceptibility to antimicrobials and decreased susceptibility to Imipenem in particular, which is a matter of great concern.

  14. Interaction between Pseudomonas and CXC Chemokines Increases Risk of Bronchiolitis Obliterans Syndrome and Death in Lung Transplantation

    Science.gov (United States)

    Wang, Xiaoyan; Weigt, S. Sam; Palchevskiy, Vyacheslav; Lynch, Joseph P.; Ross, David J.; Kubak, Bernard M.; Saggar, Rajan; Fishbein, Michael C.; Ardehali, Abbas; Li, Gang; Elashoff, Robert; Belperio, John A.

    2013-01-01

    Rationale: Pseudomonas aeruginosa is the most commonly isolated gram-negative bacterium after lung transplantation and has been shown to up-regulate glutamic acid–leucine–arginine–positive (ELR+) CXC chemokines associated with bronchiolitis obliterans syndrome (BOS), but the effect of pseudomonas on BOS and death has not been well defined. Objectives: To determine if the influence of pseudomonas isolation and ELR+ CXC chemokines on the subsequent development of BOS and the occurrence of death is time dependent. Methods: A three-state model was developed to assess the likelihood of transitioning from lung transplant (state 1) to BOS (state 2), from transplant (state 1) to death (state 3), and from BOS (state 2) to death (state 3). This Cox semi-Markovian approach determines state survival rates and cause-specific hazards for movement from one state to another. Measurements and Main Results: The likelihood of transition from transplant to BOS was increased by acute rejection, CXCL5, and the interaction between pseudomonas and CXCL1. The pseudomonas effect in this transition was due to infection rather than colonization. Movement from transplant to death was facilitated by pseudomonas infection and single lung transplant. Transition from BOS to death was affected by the length of time in state 1 and by the interactions between any pseudomonas isolation and CXCL5 and aspergillus, either independently or in combination. Conclusions: Our model demonstrates that common post-transplantation events drive movement from one post-transplantation state to another and influence outcomes differently depending upon when after transplantation they occur. Pseudomonas and the ELR+ CXC chemokines may interact to negatively influence lung transplant outcomes. PMID:23328531

  15. 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...

  16. Strain- and Substrate-Dependent Redox Mediator and Electricity Production by Pseudomonas aeruginosa.

    Science.gov (United States)

    Bosire, Erick M; Blank, Lars M; Rosenbaum, Miriam A

    2016-08-15

    Pseudomonas aeruginosa is an important, thriving member of microbial communities of microbial bioelectrochemical systems (BES) through the production of versatile phenazine redox mediators. Pure culture experiments with a model strain revealed synergistic interactions of P. aeruginosa with fermenting microorganisms whereby the synergism was mediated through the shared fermentation product 2,3-butanediol. Our work here shows that the behavior and efficiency of P. aeruginosa in mediated current production is strongly dependent on the strain of P. aeruginosa We compared levels of phenazine production by the previously investigated model strain P. aeruginosa PA14, the alternative model strain P. aeruginosa PAO1, and the BES isolate Pseudomonas sp. strain KRP1 with glucose and the fermentation products 2,3-butanediol and ethanol as carbon substrates. We found significant differences in substrate-dependent phenazine production and resulting anodic current generation for the three strains, with the BES isolate KRP1 being overall the best current producer and showing the highest electrochemical activity with glucose as a substrate (19 μA cm(-2) with ∼150 μg ml(-1) phenazine carboxylic acid as a redox mediator). Surprisingly, P. aeruginosa PAO1 showed very low phenazine production and electrochemical activity under all tested conditions. Microbial fuel cells and other microbial bioelectrochemical systems hold great promise for environmental technologies such as wastewater treatment and bioremediation. While there is much emphasis on the development of materials and devices to realize such systems, the investigation and a deeper understanding of the underlying microbiology and ecology are lagging behind. Physiological investigations focus on microorganisms exhibiting direct electron transfer in pure culture systems. Meanwhile, mediated electron transfer with natural redox compounds produced by, for example, Pseudomonas aeruginosa might enable an entire microbial

  17. Different Ancestries of R Tailocins in Rhizospheric Pseudomonas Isolates

    Science.gov (United States)

    Ghequire, Maarten G.K.; Dillen, Yörg; Lambrichts, Ivo; Proost, Paul; Wattiez, Ruddy; De Mot, René

    2015-01-01

    Bacterial genomes accommodate a variety of mobile genetic elements, including bacteriophage-related clusters that encode phage tail-like protein complexes playing a role in interactions with eukaryotic or prokaryotic cells. Such tailocins are unable to replicate inside target cells due to the lack of a phage head with associated DNA. A subset of tailocins mediate antagonistic activities with bacteriocin-like specificity. Functional characterization of bactericidal tailocins of two Pseudomonas putida rhizosphere isolates revealed not only extensive similarity with the tail assembly module of the Pseudomonas aeruginosa R-type pyocins but also differences in genomic integration site, regulatory genes, and lytic release modules. Conversely, these three features are quite similar between strains of the P. putida and Pseudomonas fluorescens clades, although phylogenetic analysis of tail genes suggests them to have evolved separately. Unlike P. aeruginosa R pyocin elements, the tailocin gene clusters of other pseudomonads frequently carry cargo genes, including bacteriocins. Compared with P. aeruginosa, the tailocin tail fiber sequences that act as specificity determinants have diverged much more extensively among the other pseudomonad species, mostly isolates from soil and plant environments. Activity of the P. putida antibacterial particles requires a functional lipopolysaccharide layer on target cells, but contrary to R pyocins from P. aeruginosa, strain susceptibilities surpass species boundaries. PMID:26412856

  18. Variation of the Pseudomonas community structure on oak leaf lettuce during storage detected by culture-dependent and -independent methods.

    Science.gov (United States)

    Nübling, Simone; Schmidt, Herbert; Weiss, Agnes

    2016-01-04

    The genus Pseudomonas plays an important role in the lettuce leaf microbiota and certain species can induce spoilage. The aim of this study was to investigate the occurrence and diversity of Pseudomonas spp. on oak leaf lettuce and to follow their community shift during a six day cold storage with culture-dependent and culture-independent methods. In total, 21 analysed partial Pseudomonas 16S rRNA gene sequences matched closely (> 98.3%) to the different reference strain sequences, which were distributed among 13 different phylogenetic groups or subgroups within the genus Pseudomonas. It could be shown that all detected Pseudomonas species belonged to the P. fluorescens lineage. In the culture-dependent analysis, 73% of the isolates at day 0 and 79% of the isolates at day 6 belonged to the P. fluorescens subgroup. The second most frequent group, with 12% of the isolates, was the P. koreensis subgroup. This subgroup was only detected at day 0. In the culture-independent analysis the P. fluorescens subgroup and P. extremaustralis could not be differentiated by RFLP. Both groups were most abundant and amounted to approximately 46% at day 0 and 79% at day 6. The phytopathogenic species P. salmonii, P. viridiflava and P. marginalis increased during storage. Both approaches identified the P. fluorescens group as the main phylogenetic group. The results of the present study suggest that pseudomonads found by plating methods indeed represent the most abundant part of the Pseudomonas community on oak leaf lettuce. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. Pf16 and phiPMW: Expanding the realm of Pseudomonas putida bacteriophages.

    Directory of Open Access Journals (Sweden)

    Damian J Magill

    Full Text Available We present the analysis of two novel Pseudomonas putida phages, pf16 and phiPMW. Pf16 represents a peripherally related T4-like phage, and is the first of its kind infecting a Pseudomonad, with evidence suggesting cyanophage origins. Extensive divergence has resulted in pf16 occupying a newly defined clade designated as the pf16-related phages, lying at the interface of the Schizo T-Evens and Exo T-Evens. Recombination with an ancestor of the P. putida phage AF is likely responsible for the tropism of this phage. phiPMW represents a completely novel Pseudomonas phage with a genome containing substantial genetic novelty through its many hypothetical proteins. Evidence suggests that this phage has been extensively shaped through gene transfer events and vertical evolution. Phylogenetics shows that this phage has an evolutionary history involving FelixO1-related viruses but is in itself highly distinct from this group.

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

    African Journals Online (AJOL)

    PRECIOUS

    2009-12-15

    Dec 15, 2009 ... protease production was 37°C at pH 9, with 2% inoculum in the medium for 24 h. .... Positive. Catalase test. Positive ... The enzyme activity gradually decreases from ... Effect of temperature on protease production by Pseudomonas fluorescens. 0 .... between RNA polymerase and upstream promotes DNA.

  1. ADHESION OF PSEUDOMONAS-FLUORESCENS TO METALLIC SURFACES

    NARCIS (Netherlands)

    VIEIRA, MJ; OLIVEIRA, R; MELO, L; PINHEIRO, M; VANDERMEI, HC

    1992-01-01

    Deposition of Pseudomonas fluorescens on aluminium, brass and copper plates was studied in a flow system. The number of bacteria deposited on aluminium was greater than on the other two types of metals. The results are discussed in terms of the mechanisms (transport and/or adhesion) that may control

  2. Oxygen regulation of nitrate uptake in denitrifying Pseudomonas aeruginosa.

    OpenAIRE

    Hernandez, D; Rowe, J J

    1987-01-01

    Oxygen had an immediate and reversible inhibitory effect on nitrate respiration by denitrifying cultures of Pseudomonas aeruginosa. Inhibition of nitrate utilization by oxygen appeared to be at the level of nitrate uptake, since nitrate reduction to nitrite in cell extracts was not affected by oxygen. The degree of oxygen inhibition was dependent on the concentration of oxygen, and increasing nitrate concentrations could not overcome the inhibition. The inhibitory effect of oxygen was maximal...

  3. An investigation of Pseudomonas aeruginosa biofilm growth on novel nanocellulose fibre dressings.

    Science.gov (United States)

    Powell, Lydia C; Khan, Saira; Chinga-Carrasco, Gary; Wright, Chris J; Hill, Katja E; Thomas, David W

    2016-02-10

    Nanocellulose from wood is a novel biomaterial, which is highly fibrillated at the nanoscale. This affords the material a number of advantages, including self-assembly, biodegradability and the ability to absorb and retain moisture, which highlights its potential usefulness in clinical wound-dressing applications. In these in vitro studies, the wound pathogen Pseudomonas aeruginosa PAO1 was used to assess the ability of two nanocellulose materials to impair bacterial growth (nanocelluloses had a relatively small fraction of residual fibres (nanocellulose films and increased cell death when compared to a commercial control wound dressing, Aquacel(®). Nanocellulose suspensions inhibited bacterial growth, whilst UV-vis spectrophotometry and laser profilometry also revealed the ability of nanocellulose to form smooth, translucent films. Atomic force microscopy studies of the surface properties of nanocellulose demonstrated that PAO1 exhibited markedly contrasting morphology when grown on the nanocellulose film surfaces compared to an Aquacel(®) control dressing (p<0.05). This study highlights the potential utility of these biodegradable materials, from a renewable source, for wound dressing applications in the prevention and treatment of biofilm development. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Emergence of Pseudomonas aeruginosa with KPC-type carbapenemase in a teaching hospital: an 8-year study.

    Science.gov (United States)

    García Ramírez, Dolores; Nicola, Federico; Zarate, Soledad; Relloso, Silvia; Smayevsky, Jorgelina; Arduino, Sonia

    2013-10-01

    An outbreak of Klebsiella pneumoniae carbapenamase (KPC)-producing K. pneumoniae occurred at our institution. Multiresistant Pseudomonas aeruginosa could have acquired this transmissible resistance mechanism, going unnoticed because its phenotypic detection in this species is difficult. We compared P. aeruginosa isolates obtained before and after the KPC-producing K. pneumoniae outbreak. No bla(KPC) genes were detected in the isolates obtained before the outbreak, whereas 33/76 (43%) of the isolates obtained after the outbreak harboured the bla(KPC) gene. P. aeruginosa may thus become a reservoir of this transmissible resistance mechanism. It is very important to understand the epidemiology of these multiresistant isolates, in order to achieve early implementation of adequate control measures to contain and reduce their dissemination in the hospital environment.

  5. Pseudomonas aeruginosa Dose-Response and Bathing Water Infection

    Science.gov (United States)

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

  6. Biosynthesis of Gold Nanoparticles Using Pseudomonas Aeruginosa

    International Nuclear Information System (INIS)

    Abd El-Aziz, M.; Badr, Y.; Mahmoud, M. A.

    2007-01-01

    Pseudomonas aeruginosa were used for extracellular biosynthesis of gold nanoparticles (Au NPs). Consequently, Au NPs were formed due to reduction of gold ion by bacterial cell supernatant of P. aeruginos ATCC 90271, P. aeruginos (2) and P. aeruginos (1). The UV-Vis. and fluorescence spectra of the bacterial as well as chemical prepared Au NPs were recorded. Transmission electron microscopy (TEM) micrograph showed the formation of well-dispersed gold nanoparticles in the range of 15-30 nm. The process of reduction being extracellular and may lead to the development of an easy bioprocess for synthesis of Au NPs

  7. Hydrocarbonoclastic bacteria of the genus Pseudomonas in Samanea saman (Jacq. Merr. rhizosphere

    Directory of Open Access Journals (Sweden)

    Juliana Coromoto Mayz

    2017-01-01

    Full Text Available The research goal includes isolation, characterization and identification of Pseudomonas species existing in the rhizosphere of a legume present (colonizing or survivor in a savanna soil polluted by an oil spill, in order to explain the support of the growth of this leguminous plant through the reduction of the toxicity of spilled oil (hydrocarbonoclastic effects. The site is located at Amana del Tamarindo village entrance, Monagas State, Venezuela (9 ° 38' 52 "N, 63 ° 7' 20" E, 46 masl. An area of 50 m2 was sampled.  In concordance to the descriptions, keys, and comparison with the UOJ Herbarium exsiccatae, the legume collected was identified as Samanea saman (Jacq. Merr., which belongs to the Fabaceae family. The results of the biochemical characterization and the production of pyocyanine and fluorescein pigments allowed identifying 10 isolates as P. fluorescens, 5 as P. putida and 5 as P. aeruginosa. Samanea saman is recommended for re-vegetation of the contaminated area.

  8. A Natural Chimeric Pseudomonas Bacteriocin with Novel Pore-Forming Activity Parasitizes the Ferrichrome Transporter.

    Science.gov (United States)

    Ghequire, Maarten G K; Kemland, Lieselore; Anoz-Carbonell, Ernesto; Buchanan, Susan K; De Mot, René

    2017-02-21

    Modular bacteriocins represent a major group of secreted protein toxins with a narrow spectrum of activity, involved in interference competition between Gram-negative bacteria. These antibacterial proteins include a domain for binding to the target cell and a toxin module at the carboxy terminus. Self-inhibition of producers is provided by coexpression of linked immunity genes that transiently inhibit the toxin's activity through formation of bacteriocin-immunity complexes or by insertion in the inner membrane, depending on the type of toxin module. We demonstrate strain-specific inhibitory activity for PmnH, a Pseudomonas bacteriocin with an unprecedented dual-toxin architecture, hosting both a colicin M domain, potentially interfering with peptidoglycan synthesis, and a novel colicin N-type domain, a pore-forming module distinct from the colicin Ia-type domain in Pseudomonas aeruginosa pyocin S5. A downstream-linked gene product confers PmnH immunity upon susceptible strains. This protein, ImnH, has a transmembrane topology similar to that of Pseudomonas colicin M-like and pore-forming immunity proteins, although homology with either of these is essentially absent. The enhanced killing activity of PmnH under iron-limited growth conditions reflects parasitism of the ferrichrome-type transporter for entry into target cells, a strategy shown here to be used as well by monodomain colicin M-like bacteriocins from pseudomonads. The integration of a second type of toxin module in a bacteriocin gene could offer a competitive advantage against bacteria displaying immunity against only one of both toxic activities. IMPORTANCE In their continuous struggle for ecological space, bacteria face a huge load of contenders, including phylogenetically related strains that compete for the same niche. One important group of secreted antibacterial proteins assisting in eliminating these rivals are modular bacteriocins of Gram-negative bacteria, comprising a domain for docking onto the

  9. In vitro efficacy of doripenem against pseudomonas aeruginosa and acinetobacter baumannii by e-test

    International Nuclear Information System (INIS)

    Gilani, M.; Munir, T.; Latif, M.; Rehman, S.

    2015-01-01

    To assess the in vitro efficacy of doripenem against Pseudomonas aeruginosa and Acinetobacter baumannii using Epsilometer strips. Study Design: Cross-sectional study. Place and Duration of Study: Department of Microbiology, Army Medical College, Rawalpindi and National University of Sciences and Technology, Islamabad, from May 2014 to September 2014. Methodology: A total of 60 isolates of Acinetobacter baumannii and Pseudomonas aeruginosa collected from various clinical samples received from Military Hospital were included in the study. The specimens were inoculated onto blood, MacConkey and chocolate agars. The isolates were identified using Gram staining, motility, catalase test, oxidase test and API 20NE (Biomeriux, France). Organisms identified as Acinetobacter baumannii and Pseudomonas aeruginosa were included in the study. Bacterial suspensions equivalent to 0.5 McFarland turbidity standard of the isolates were prepared and applied on Mueller Hinton agar. Epsilometer strip was placed in the center of the plate and incubated for 18-24 hours. Minimum Inhibitory Concentration (MIC) was taken to be the point where the epsilon intersected the E-strip. MIC of all the isolates was noted. Results: For Pseudomonas aeruginosa isolates, MIC50 was 12 micro g/mL and MIC90 was 32 micro g/mL. For Acinetobacter baumannii MIC 50 and MIC90 was 32 micro g/mL. Conclusion: Doripenem is no more effective against Pseudomonas aeruginosa and Acinetobacter baumannii in our setting. (author)

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

    African Journals Online (AJOL)

    sonal

    2015-04-08

    Apr 8, 2015 ... Author(s) agree that this article remains permanently open access under the terms of ... grown in nutrient broth overnight, pond water, mucus and kidney ... a rapid test for detection of Pseudomonas strains in milk is required.

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

    Energy Technology Data Exchange (ETDEWEB)

    Gorbunova, S.A.; Yanenko, A.S.; Akhverdyan, V.Z.; Reulets, M.A.; Krylov, V.N.

    1986-03-01

    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.

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

    International Nuclear Information System (INIS)

    Gorbunova, S.A.; Yanenko, A.S.; Akhverdyan, V.Z.; Reulets, M.A.; Krylov, V.N.

    1986-01-01

    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

  13. Complement activation by Pseudomonas aeruginosa biofilms

    DEFF Research Database (Denmark)

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

    1993-01-01

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

  14. 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.)

  15. Carbapenem stewardship: does ertapenem affect Pseudomonas susceptibility to other carbapenems? A review of the evidence.

    Science.gov (United States)

    Nicolau, David P; Carmeli, Yehuda; Crank, Christopher W; Goff, Debra A; Graber, Christopher J; Lima, Ana Lucia L; Goldstein, Ellie J C

    2012-01-01

    The group 2 carbapenems (imipenem, meropenem and, more recently, doripenem) have been a mainstay of treatment for patients with serious hospital infections caused by Pseudomonas aeruginosa, Enterobacteriaceae and other difficult-to-treat Gram-negative pathogens as well as mixed aerobic/anaerobic infections. When ertapenem, a group 1 carbapenem, was introduced, questions were raised about the potential for ertapenem to select for imipenem- and meropenem-resistant Pseudomonas. Results from ten clinical studies evaluating the effect of ertapenem use on the susceptibility of Pseudomonas to carbapenems have uniformly shown that ertapenem use does not result in decreased Pseudomonas susceptibility to these antipseudomonal carbapenems. Here we review these studies evaluating the evidence of how ertapenem use affects P. aeruginosa as well as provide considerations for ertapenem use in the context of institutional stewardship initiatives. Copyright © 2011 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved.

  16. Detection of Pseudomonas aeruginosa Metabolite Pyocyanin in Water and Saliva by Employing the SERS Technique

    Directory of Open Access Journals (Sweden)

    Olga Žukovskaja

    2017-07-01

    Full Text Available Pyocyanin (PYO is a metabolite specific for Pseudomonas aeruginosa. In the case of immunocompromised patients, it is currently considered a biomarker for life-threating Pseudomonas infections. In the frame of this study it is shown, that PYO can be detected in aqueous solution by employing surface-enhanced Raman spectroscopy (SERS combined with a microfluidic platform. The achieved limit of detection is 0.5 μM. This is ~2 orders of magnitude below the concentration of PYO found in clinical samples. Furthermore, as proof of principle, the SERS detection of PYO in the saliva of three volunteers was also investigated. This body fluid can be collected in a non-invasive manner and is highly chemically complex, making the detection of the target molecule challenging. Nevertheless, PYO was successfully detected in two saliva samples down to 10 μM and in one sample at a concentration of 25 μM. This indicates that the molecules present in saliva do not inhibit the efficient adsorption of PYO on the surface of the employed SERS active substrates.

  17. Precision-engineering the Pseudomonas aeruginosa genome with two-step allelic exchange

    DEFF Research Database (Denmark)

    Hmelo, Laura R; Borlee, Bradley R; Almblad, Henrik

    2015-01-01

    Allelic exchange is an efficient method of bacterial genome engineering. This protocol describes the use of this technique to make gene knockouts and knock-ins, as well as single-nucleotide insertions, deletions and substitutions, in Pseudomonas aeruginosa. Unlike other approaches to allelic exch...

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

    African Journals Online (AJOL)

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

  19. Sodium lauryl ether sulfate (SLES) degradation by nitrate-reducing bacteria.

    Science.gov (United States)

    Paulo, Ana M S; Aydin, Rozelin; Dimitrov, Mauricio R; Vreeling, Harm; Cavaleiro, Ana J; García-Encina, Pedro A; Stams, Alfons J M; Plugge, Caroline M

    2017-06-01

    The surfactant sodium lauryl ether sulfate (SLES) is widely used in the composition of detergents and frequently ends up in wastewater treatment plants (WWTPs). While aerobic SLES degradation is well studied, little is known about the fate of this compound in anoxic environments, such as denitrification tanks of WWTPs, nor about the bacteria involved in the anoxic biodegradation. Here, we used SLES as sole carbon and energy source, at concentrations ranging from 50 to 1000 mg L -1 , to enrich and isolate nitrate-reducing bacteria from activated sludge of a WWTP with the anaerobic-anoxic-oxic (A 2 /O) concept. In the 50 mg L -1 enrichment, Comamonas (50%), Pseudomonas (24%), and Alicycliphilus (12%) were present at higher relative abundance, while Pseudomonas (53%) became dominant in the 1000 mg L -1 enrichment. Aeromonas hydrophila strain S7, Pseudomonas stutzeri strain S8, and Pseudomonas nitroreducens strain S11 were isolated from the enriched cultures. Under denitrifying conditions, strains S8 and S11 degraded 500 mg L -1 SLES in less than 1 day, while strain S7 required more than 6 days. Strains S8 and S11 also showed a remarkable resistance to SLES, being able to grow and reduce nitrate with SLES concentrations up to 40 g L -1 . Strain S11 turned out to be the best anoxic SLES degrader, degrading up to 41% of 500 mg L -1 . The comparison between SLES anoxic and oxic degradation by strain S11 revealed differences in SLES cleavage, degradation, and sulfate accumulation; both ester and ether cleavage were probably employed in SLES anoxic degradation by strain S11.

  20. Two cases of Pseudomonas aeruginosa epidural abscesses and cervical osteomyelitis after dental extractions.

    Science.gov (United States)

    Walters, Heather L; Measley, Robert

    2008-04-20

    Case report. To report 2 unusual cases of Pseudomonas aeruginosa epidural abscesses and cervical osteomyelitis after routine dental extractions and to review relevant literature. Pseudomonas aeruginosa is a rare cause of cervical osteomyelitis in patients after dental extractions. Only 1 prior case could be found in the literature. The cases of an 18-year-old male and a 23-year-old female are presented. PubMed was used to search for relevant literature. Our 2 patients presented with excruciating neck pain within 24 hours of routine dental extractions and, by imaging were found to have cervical epidural abscesses and osteomyelitis. Both patients were taken to the operating room for drainage and corpectomy and treated with prolonged courses of intravenous antibiotics. When seen in follow up 3 months later, neither patient demonstrated any neurologic sequelae. Pseudomonas aeruginosa epidural abscesses and osteomyelitis of the cervical spine have only rarely been reported in healthy patients after dental extractions. To our knowledge, the 2 patients reported here are only the second 2 such cases reported in the literature. Unfortunately, as in prior cases, these 2 patients had a significant delay in diagnosis. Therefore, a strong suspicion must be maintained for all patients presenting with neck pain after a recent dental extraction and appropriate imaging must be obtained urgently.

  1. Antimicrobial activity of gallic acid against food-related Pseudomonas strains and its use as biocontrol tool to improve the shelf life of fresh black truffles.

    Science.gov (United States)

    Sorrentino, Elena; Succi, Mariantonietta; Tipaldi, Luca; Pannella, Gianfranco; Maiuro, Lucia; Sturchio, Marina; Coppola, Raffaele; Tremonte, Patrizio

    2018-02-02

    Refrigeration alone or in combination with other technologies represents the main tool used in the last decades to preserve the freshness of black truffles. This is principally due to the delicateness and vulnerability of this edible hypogeous fungus, so that other invasive preservation practices cannot be adopted. However, the proliferation of some microbial species during the cold storage still represents an unsolved problem. Pseudomonads are among the main spoiler bacteria responsible for the deterioration of refrigerated black truffles. Their growth ability at low temperatures requires the use of additional hurdles to prolong the shelf-life of truffles without altering their major features. The use of natural compounds may represent an alternative system for the biocontrol of this kind of product. Specifically, gallic acid (GA) is a phenolic acid naturally present in different foods, whose effectiveness was in vitro demonstrated against Pseudomonas spp. In our study, we reported the antimicrobial activity expressed by GA not only in vitro, using as target bacteria Pseudomonas putida DSMZ 291 T , P. fluorescens DSMZ 50090 T , P. fragi DSMZ 3456 T and Pseudomonas spp. P30-4, previously isolated from black truffles, but also in situ on fresh black truffles stored at 4°C for 28days. Our results showed Minimum Inhibitory Concentrations (MIC) of 2.5mg/mL GA for all tested strains, except for P. fluorescens DSMZ 50090 T , having a MIC corresponding to 5mg/mL GA. The Minimum Bactericidal Concentration (MBC) was 10mg/mL for all strains. The analysis of kinetic parameters showed that the survival declined passing from 2.5 to 10mg/mL GA concentrations, with P. fluorescens confirmed to be the most resistant strain. Moreover, images obtained from Scanning Electron Microscopy revealed that Pseudomonas cells were strongly injured by the treatment with GA at 2.5mg/mL concentration, displaying visible pores on the cellular surfaces, absence of flagella and lysis with loss of

  2. Computational prediction of the Crc regulon identifies genus-wide and species-specific targets of catabolite repression control in Pseudomonas bacteria

    Directory of Open Access Journals (Sweden)

    O'Gara Fergal

    2010-11-01

    Full Text Available Abstract Background Catabolite repression control (CRC is an important global control system in Pseudomonas that fine tunes metabolism in order optimise growth and metabolism in a range of different environments. The mechanism of CRC in Pseudomonas spp. centres on the binding of a protein, Crc, to an A-rich motif on the 5' end of an mRNA resulting in translational down-regulation of target genes. Despite the identification of several Crc targets in Pseudomonas spp. the Crc regulon has remained largely unexplored. Results In order to predict direct targets of Crc, we used a bioinformatics approach based on detection of A-rich motifs near the initiation of translation of all protein-encoding genes in twelve fully sequenced Pseudomonas genomes. As expected, our data predict that genes related to the utilisation of less preferred nutrients, such as some carbohydrates, nitrogen sources and aromatic carbon compounds are targets of Crc. A general trend in this analysis is that the regulation of transporters is conserved across species whereas regulation of specific enzymatic steps or transcriptional activators are often conserved only within a species. Interestingly, some nucleoid associated proteins (NAPs such as HU and IHF are predicted to be regulated by Crc. This finding indicates a possible role of Crc in indirect control over a subset of genes that depend on the DNA bending properties of NAPs for expression or repression. Finally, some virulence traits such as alginate and rhamnolipid production also appear to be regulated by Crc, which links nutritional status cues with the regulation of virulence traits. Conclusions Catabolite repression control regulates a broad spectrum of genes in Pseudomonas. Some targets are genus-wide and are typically related to central metabolism, whereas other targets are species-specific, or even unique to particular strains. Further study of these novel targets will enhance our understanding of how Pseudomonas

  3. Computational prediction of the Crc regulon identifies genus-wide and species-specific targets of catabolite repression control in Pseudomonas bacteria.

    Science.gov (United States)

    Browne, Patrick; Barret, Matthieu; O'Gara, Fergal; Morrissey, John P

    2010-11-25

    Catabolite repression control (CRC) is an important global control system in Pseudomonas that fine tunes metabolism in order optimise growth and metabolism in a range of different environments. The mechanism of CRC in Pseudomonas spp. centres on the binding of a protein, Crc, to an A-rich motif on the 5' end of an mRNA resulting in translational down-regulation of target genes. Despite the identification of several Crc targets in Pseudomonas spp. the Crc regulon has remained largely unexplored. In order to predict direct targets of Crc, we used a bioinformatics approach based on detection of A-rich motifs near the initiation of translation of all protein-encoding genes in twelve fully sequenced Pseudomonas genomes. As expected, our data predict that genes related to the utilisation of less preferred nutrients, such as some carbohydrates, nitrogen sources and aromatic carbon compounds are targets of Crc. A general trend in this analysis is that the regulation of transporters is conserved across species whereas regulation of specific enzymatic steps or transcriptional activators are often conserved only within a species. Interestingly, some nucleoid associated proteins (NAPs) such as HU and IHF are predicted to be regulated by Crc. This finding indicates a possible role of Crc in indirect control over a subset of genes that depend on the DNA bending properties of NAPs for expression or repression. Finally, some virulence traits such as alginate and rhamnolipid production also appear to be regulated by Crc, which links nutritional status cues with the regulation of virulence traits. Catabolite repression control regulates a broad spectrum of genes in Pseudomonas. Some targets are genus-wide and are typically related to central metabolism, whereas other targets are species-specific, or even unique to particular strains. Further study of these novel targets will enhance our understanding of how Pseudomonas bacteria integrate nutritional status cues with the regulation

  4. Computational prediction of the Crc regulon identifies genus-wide and species-specific targets of catabolite repression control in Pseudomonas bacteria

    LENUS (Irish Health Repository)

    Browne, Patrick

    2010-11-25

    Abstract Background Catabolite repression control (CRC) is an important global control system in Pseudomonas that fine tunes metabolism in order optimise growth and metabolism in a range of different environments. The mechanism of CRC in Pseudomonas spp. centres on the binding of a protein, Crc, to an A-rich motif on the 5\\' end of an mRNA resulting in translational down-regulation of target genes. Despite the identification of several Crc targets in Pseudomonas spp. the Crc regulon has remained largely unexplored. Results In order to predict direct targets of Crc, we used a bioinformatics approach based on detection of A-rich motifs near the initiation of translation of all protein-encoding genes in twelve fully sequenced Pseudomonas genomes. As expected, our data predict that genes related to the utilisation of less preferred nutrients, such as some carbohydrates, nitrogen sources and aromatic carbon compounds are targets of Crc. A general trend in this analysis is that the regulation of transporters is conserved across species whereas regulation of specific enzymatic steps or transcriptional activators are often conserved only within a species. Interestingly, some nucleoid associated proteins (NAPs) such as HU and IHF are predicted to be regulated by Crc. This finding indicates a possible role of Crc in indirect control over a subset of genes that depend on the DNA bending properties of NAPs for expression or repression. Finally, some virulence traits such as alginate and rhamnolipid production also appear to be regulated by Crc, which links nutritional status cues with the regulation of virulence traits. Conclusions Catabolite repression control regulates a broad spectrum of genes in Pseudomonas. Some targets are genus-wide and are typically related to central metabolism, whereas other targets are species-specific, or even unique to particular strains. Further study of these novel targets will enhance our understanding of how Pseudomonas bacteria integrate

  5. Biosurfactant production by Pseudomonas aeruginosain kefir and fish meal.

    Science.gov (United States)

    Kaskatepe, Banu; Yildiz, Sulhiye; Gumustas, Mehmet; Ozkan, Sibel A

    2015-01-01

    The aim of this study was to increase rhamnolipid production by formulating media using kefir and fish meal for Pseudomonas aeruginosa strains isolated from different environmental resources. The strains, named as H1, SY1, and ST1, capable of rhamnolipid production were isolated from soil contaminated with wastes originating from olive and fish oil factories. Additionally, P. aeruginosa ATCC 9027 strain, which is known as rhamnolipid producer, was included in the study. Initially, rhamnolipid production by the strains was determined in Mineral Salt Medium (MSM) and then in media prepared by using kefir and fish meal. The obtained rhamnolipids were purified and quantified according to Dubois et al. (1956). The quantity of rhamnolipids of ATCC, H1 and SY1 strains in kefir media were determined as 11.7 g/L, 10.8 g/L and 3.2 g/L, respectively, and in fish meal media as 12.3 g/L, 9.3 g/L and 10.3 g/L, respectively. In addition, effect of UV light exposure on rhamnolipid production was also investigated but contrary a decrease was observed. The results indicate that P. aeruginosa strains isolated from various environmental resources used in this study can be important due to their rhamnolipid yield, and fish meal, which is obtained from waste of fish, can be an alternative source in low cost rhamnolipid production.

  6. Biosurfactant production by Pseudomonas aeruginosain kefir and fish meal

    Directory of Open Access Journals (Sweden)

    Banu Kaskatepe

    2015-09-01

    Full Text Available The aim of this study was to increase rhamnolipid production by formulating media using kefir and fish meal for Pseudomonas aeruginosa strains isolated from different environmental resources. The strains, named as H1, SY1, and ST1, capable of rhamnolipid production were isolated from soil contaminated with wastes originating from olive and fish oil factories. Additionally, P. aeruginosa ATCC 9027 strain, which is known as rhamnolipid producer, was included in the study. Initially, rhamnolipid production by the strains was determined in Mineral Salt Medium (MSM and then in media prepared by using kefir and fish meal. The obtained rhamnolipids were purified and quantified according to Dubois et al. (1956. The quantity of rhamnolipids of ATCC, H1 and SY1 strains in kefir media were determined as 11.7 g/L, 10.8 g/L and 3.2 g/L, respectively, and in fish meal media as 12.3 g/L, 9.3 g/L and 10.3 g/L, respectively. In addition, effect of UV light exposure on rhamnolipid production was also investigated but contrary a decrease was observed. The results indicate that P. aeruginosa strains isolated from various environmental resources used in this study can be important due to their rhamnolipid yield, and fish meal, which is obtained from waste of fish, can be an alternative source in low cost rhamnolipid production.

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

    African Journals Online (AJOL)

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

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

    African Journals Online (AJOL)

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

  9. Bioleaching of Gold and Silver from Waste Printed Circuit Boards by Pseudomonas balearica SAE1 Isolated from an e-Waste Recycling Facility.

    Science.gov (United States)

    Kumar, Anil; Saini, Harvinder Singh; Kumar, Sudhir

    2018-02-01

    Indigenous bacterial strain Pseudomonas balearica SAE1, tolerant to e-waste toxicity was isolated from an e-waste recycling facility Exigo Recycling Pvt. Ltd., India. Toxicity tolerance of bacterial strain was analyzed using crushed (particle size ≤150 µm) waste computer printed circuit boards (PCBs)/liter (L) of culture medium. The EC 50 value for SAE1 was 325.7 g/L of the e-waste pulp density. Two-step bioleaching was then applied to achieve the dissolution of gold (Au) and silver (Ag) from the e-waste. To maximize precious metal dissolution, factors including pulp density, glycine concentration, pH level, and temperature were optimized. The optimization resulted in 68.5 and 33.8% of Au and Ag dissolution, respectively, at a pH of 9.0, a pulp density of 10 g/L, a temperature of 30 °C, and a glycine concentration of 5 g/L. This is the first study of Au and Ag bioleaching using indigenous e-waste bacteria and its analysis to determine e-waste toxicity tolerance.

  10. Alkaline cyanide degradation by Pseudomonas pseudoalcaligenes CECT5344 in a batch reactor. Influence of pH

    International Nuclear Information System (INIS)

    Huertas, M.J.; Saez, L.P.; Roldan, M.D.; Luque-Almagro, V.M.; Martinez-Luque, M.; Blasco, R.; Castillo, F.; Moreno-Vivian, C.; Garcia-Garcia, I.

    2010-01-01

    Water containing cyanide was biologically detoxified with the bacterial strain Pseudomonas pseudoalcaligenes CECT5344 in a batch reactor. Volatilization of toxic hydrogen cyanide (HCN) was avoided by using an alkaline medium for the treatment. The operational procedure was optimized to assess cyanide biodegradation at variable pH values and dissolved oxygen concentrations. Using an initial pH of 10 without subsequent adjustment allowed total cyanide to be consumed at a mean rate of approximately 2.81 mg CN - L -1 O.D. -1 h -1 ; however, these conditions posed a high risk of HCN formation. Cyanide consumption was found to be pH-dependent. Thus, no bacterial growth was observed with a controlled pH of 10; on the other hand, pH 9.5 allowed up to 2.31 mg CN - L -1 O.D. -1 h -1 to be converted. The combination of a high pH and a low dissolved oxygen saturation (10%) minimized the release of HCN. This study contributes new basic knowledge about this biological treatment, which constitutes an effective alternative to available physico-chemical methods for the purification of wastewater containing cyanide or cyano-metal complexes.

  11. Baicalin inhibits biofilm formation, attenuates the quorum sensing-controlled virulence and enhances Pseudomonas aeruginosa clearance in a mouse peritoneal implant infection model.

    Directory of Open Access Journals (Sweden)

    Jing Luo

    Full Text Available The quorum sensing (QS circuit plays a role in the precise regulation of genes controlling virulence factors and biofilm formation in Pseudomonas aeruginosa. QS-controlled biofilm formation by Pseudomonas aeruginosa in clinical settings has remained controversial due to emerging drug resistance; therefore, screening diverse compounds for anti-biofilm or anti-QS activities is important. This study demonstrates the ability of sub-minimum inhibitory concentrations (sub-MICs of baicalin, an active natural compound extracted from the traditional Chinese medicinal Scutellaria baicalensis, to inhibit the formation of Pseudomonas aeruginosa biofilms and enhance the bactericidal effects of various conventional antibiotics in vitro. In addition, baicalin exerted dose-dependent inhibitory effects on virulence phenotypes (LasA protease, LasB elastase, pyocyanin, rhamnolipid, motilities and exotoxin A regulated by QS in Pseudomonas aeruginosa. Moreover, the expression levels of QS-regulatory genes, including lasI, lasR, rhlI, rhlR, pqsR and pqsA, were repressed after sub-MIC baicalin treatment, resulting in significant decreases in the QS signaling molecules 3-oxo-C12-HSL and C4-HSL, confirming the ability of baicalin-mediated QS inhibition to alter gene and protein expression. In vivo experiments indicated that baicalin treatment reduces Pseudomonas aeruginosa pathogenicity in Caenorhabditis elegans. Greater worm survival in the baicalin-treated group manifested as an increase in the LT50 from 24 to 96 h. In a mouse peritoneal implant infection model, baicalin treatment enhanced the clearance of Pseudomonas aeruginosa from the implants of mice infected with Pseudomonas aeruginosa compared with the control group. Moreover, the combination of baicalin and antibiotics significantly reduced the numbers of colony-forming units in the implants to a significantly greater degree than antibiotic treatment alone. Pathological and histological analyses revealed

  12. Ocorrência de linhagens de Pseudomonas aeruginosa cloro resistentes em águas de diferentes origens = Ocurrence of chlorine resistant strains of Pseudomonas aeruginosa from different water sources

    Directory of Open Access Journals (Sweden)

    Glícia Maria Torres Calazans

    2007-07-01

    Full Text Available Pseudomonas aeruginosa é conhecida por sua versatilidade metabólica e extrema capacidade de adaptação a diferentes ambientes, inclusive aquáticos. Para desinfecção de águas, o cloro e agentes que contêm cloro continuam sendo os mais usados no mundo. O objetivo deste trabalho foi avaliar a resistência ao cloro de linhagens de P. aeruginosa, isoladas de amostras de águas de diversos ambientes. Foram testados diferentes tempos de contato (1, 5, 10, 20, 30 e 40 minutos e soluções aquosas de cloro, com concentrações definidascom base na legislação vigente no país para água potável: 0,5; 1,0 e 2,0 ppm. O teste de resistência ao cloro foi desenvolvido por meio da exposição direta das bactérias às soluções. Os resultados revelaram que P. aeruginosa, isoladas de diferentes fontes de água, têm ahabilidade de sobreviver a diferentes concentrações de cloro. Na concentração de 1 ppm, a maioria das linhagens não foi inibida. As linhagens mais resistentes ao cloro também apresentaram relação de multirresistência à maioria dos antibióticos testados.The nutritional versatility and the adaptability of Pseudomonas aeruginosa to different environments, including water, are well known. Chlorine and other chlorine agents are used as water disinfecting all around the world. The aim of this work was to evaluate the possible chlorine resistance amongst P. aeruginosa strains isolated from different aquatic sources by using different contact time (1, 5, 10, 20, 30 and 40 minutes in solutions with known chlorine concentrations according current legislation in the country to potable water: 0.5; 1.0 and 2.0 ppm. The chlorine resistance test was done by direct exposure of P. aeruginosa under a solution with known chlorine concentration. Results showed that P. aeruginosa strains isolated from different aquatic sources are able tosurvive in different chlorine concentrations. At 1 ppm, most of them were not inhibited. It was also observed

  13. Pseudomonas-related populations associated with reverse osmosis in drinking water treatment.

    Science.gov (United States)

    Sala-Comorera, Laura; Blanch, Anicet R; Vilaró, Carles; Galofré, Belén; García-Aljaro, Cristina

    2016-11-01

    Reverse osmosis membrane filtration technology (RO) is used to treat drinking water. After RO treatment, bacterial growth is still observed in water. However, it is not clear whether those microorganisms belong to species that can pose a health risk, such as Pseudomonas spp. The goal of this study is to characterize the bacterial isolates from a medium that is selective for Pseudomonas and Aeromonas which were present in the water fraction before and after the RO. To this end, isolates were recovered over two years and were identified by matrix-assisted laser desorption/ionization-time of flight mass spectrometry. They were then biochemically phenotyped and the population similarity indexes were calculated. The isolates were analysed for their capacity to form biofilms in vitro and antimicrobial susceptibility. There were significant differences between the microbial populations in water before and after RO. Furthermore, the structures of the populations analysed at the same sampling point were similar in different sampling campaigns. Some of the isolates had the capacity to form a biofilm and showed resistance to different antibiotics. A successful level filtration via RO and subsequent recolonization of the membrane with different species from those in the feed water was found. Pseudomonas aeruginosa was not recovered from among the isolates. This study increases the knowledge on the microorganisms present in water after RO treatment, with focus in one of the genus causing problems in RO systems associated with human health risk, Pseudomonas. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Isolation and partial characterization of protease from Pseudomonas aeruginosa ATCC 27853

    Directory of Open Access Journals (Sweden)

    LIDIJA IZRAEL-ŽIVKOVIĆ

    2010-08-01

    Full Text Available Enzymatic characteristics of a protease from a medically important, referent strain of Pseudomonas aeruginosa ATCC 27853 were determined. According to sodium dodecyl sulfate polyacrylamide gel electrophoresis, SDS-PAGE, and gel filtration, it was estimated that the molecular mass of the purified enzyme was about 15 kDa. Other enzymatic properties were found to be: pH optimum 7.1, pH stability between 6.5 and 10; temperature optimum around 60 °C while the enzyme was stable at 60 °C for 30 min. Inhibition of the enzyme was observed with metal chelators, such as EDTA and 1,10-phenanthroline, suggesting that the protease is a metalloenzyme. Furthermore, the enzyme contains one mole of zinc ion per mole of enzyme. The protease was stable in the presence of different organic solvents, which enables its potential use for the synthesis of peptides.

  15. Pseudomonas biofilms: possibilities of their control

    Czech Academy of Sciences Publication Activity Database

    Masák, J.; Čejková, A.; Schreiberová, O.; Řezanka, Tomáš

    2014-01-01

    Roč. 89, č. 2 (2014), s. 1-14 ISSN 0168-6496 R&D Projects: GA ČR GA14-23597S; GA ČR GA14-00227S Grant - others:Ministry of Industry and Trade(CZ) FR-TI1/456; Ministry of Education, Youth and Sports(CZ) LF11016 Institutional support: RVO:61388971 Keywords : biofilm * pseudomonas * review Subject RIV: EE - Microbiology, Virology Impact factor: 3.568, year: 2014

  16. 33 original article infections a pseudomonas aeruginosa dans un

    African Journals Online (AJOL)

    boaz

    COPYRIGHT 2014. AFR. J. CLN. EXPER. .... Effective management of P. aeruginosa infections requires good ... a guide for doctors managing patients with. Pseudomonas .... Principles and practice of infectious diseases.5th edition. Edited by ...

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

    African Journals Online (AJOL)

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

  18. Adaptation of Pseudomonas aeruginosa to the cystic fibrosis airway: an evolutionary perspective

    DEFF Research Database (Denmark)

    Folkesson, Anders; Jelsbak, Lars; Yang, Lei

    2012-01-01

    evolves from a state of early, recurrent intermittent colonization of the airways of patients with CF to a chronic infection state, and how this process offers opportunities to study bacterial evolution in natural environments. We believe that such studies are valuable not only for our understanding......The airways of patients with cystic fibrosis (CF) are nearly always infected with many different microorganisms. This environment offers warm, humid and nutrient-rich conditions, but is also stressful owing to frequent antibiotic therapy and the host immune response. Pseudomonas aeruginosa...... is commonly isolated from the airways of patients with CF, where it most often establishes chronic infections that usually persist for the rest of the lives of the patients. This bacterium is a major cause of mortality and morbidity and has therefore been studied intensely. Here, we discuss how P. aeruginosa...

  19. Development of a lipase fermentation process that uses a recombinant Pseudomonas alcaligenes strain

    NARCIS (Netherlands)

    Gerritse, G; Hommes, R.W J; Quax, Wim

    Pseudomonas alcaligenes M-l secretes an alkaline lipase, which has excellent characteristics for the removal of fatty stains under modern washing conditions. A fed-batch fermentation process based on the secretion of the alkaline lipase from P. alcaligenes was developed. Due to the inability of P.

  20. Pseudomonas aestus sp. nov., a plant growth-promoting bacterium isolated from mangrove sediments.

    Science.gov (United States)

    Vasconcellos, Rafael L F; Santos, Suikinai Nobre; Zucchi, Tiago Domingues; Silva, Fábio Sérgio Paulino; Souza, Danilo Tosta; Melo, Itamar Soares

    2017-10-01

    Strain CMAA 1215 T , a Gram-reaction-negative, aerobic, catalase positive, polarly flagellated, motile, rod-shaped (0.5-0.8 × 1.3-1.9 µm) bacterium, was isolated from mangrove sediments, Cananéia Island, Brazil. Analysis of the 16S rRNA gene sequences showed that strain CMAA 1215 T forms a distinct phyletic line within the Pseudomonas putida subclade, being closely related to P. plecoglossicida ATCC 700383 T , P. monteilii NBRC 103158 T , and P. taiwanensis BCRC 17751 T of sequence similarity of 98.86, 98.73, and 98.71%, respectively. Genomic comparisons of the strain CMAA 1215 T with its closest phylogenetic type strains using average nucleotide index (ANI) and DNA:DNA relatedness approaches revealed 84.3-85.3% and 56.0-63.0%, respectively. A multilocus sequence analysis (MLSA) performed concatenating 16S rRNA, gyrB and rpoB gene sequences from the novel species was related with Pseudomonas putida subcluster and formed a new phylogenetic lineage. The phenotypic, physiological, biochemical, and genetic characteristics support the assignment of CMAA 1215 T to the genus Pseudomonas, representing a novel species. The name Pseudomonas aestus sp.nov. is proposed, with CMAA 1215 T (=NRRL B-653100 T  = CBMAI 1962 T ) as the type strain.

  1. Metabolic engineering of Pseudomonas fluorescens for the production of vanillin from ferulic acid.

    Science.gov (United States)

    Di Gioia, Diana; Luziatelli, Francesca; Negroni, Andrea; Ficca, Anna Grazia; Fava, Fabio; Ruzzi, Maurizio

    2011-12-20

    Vanillin is one of the most important flavors in the food industry and there is great interest in its production through biotechnological processes starting from natural substrates such as ferulic acid. Among bacteria, recombinant Escherichia coli strains are the most efficient vanillin producers, whereas Pseudomonas spp. strains, although possessing a broader metabolic versatility, rapidly metabolize various phenolic compounds including vanillin. In order to develop a robust Pseudomonas strain that can produce vanillin in high yields and at high productivity, the vanillin dehydrogenase (vdh)-encoding gene of Pseudomonas fluorescens BF13 strain was inactivated via targeted mutagenesis. The results demonstrated that engineered derivatives of strain BF13 accumulate vanillin if inactivation of vdh is associated with concurrent expression of structural genes for feruloyl-CoA synthetase (fcs) and hydratase/aldolase (ech) from a low-copy plasmid. The conversion of ferulic acid to vanillin was enhanced by optimization of growth conditions, growth phase and parameters of the bioconversion process. The developed strain produced up to 8.41 mM vanillin, which is the highest final titer of vanillin produced by a Pseudomonas strain to date and opens new perspectives in the use of bacterial biocatalysts for biotechnological production of vanillin from agro-industrial wastes which contain ferulic acid. Copyright © 2011 Elsevier B.V. All rights reserved.

  2. Methods of detecting and controlling mucoid Pseudomonas biofilm production

    Science.gov (United States)

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

    2013-01-01

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

  3. Biodegradation of propargite by Pseudomonas putida, isolated from tea rhizosphere.

    Science.gov (United States)

    Sarkar, Soumik; Seenivasan, Subbiah; Asir, Robert Premkumar Samuel

    2010-02-15

    Biodegradation of miticide propargite was carried out in vitro by selected Pseudomonas strains isolated from tea rhizosphere. A total number of 13 strains were isolated and further screened based on their tolerance level to different concentrations of propargite. Five best strains were selected and further tested for their nutritional requirements. Among the different carbon sources tested glucose exhibited the highest growth promoting capacity and among nitrogen sources ammonium nitrate supported the growth to the maximum. The five selected Pseudomonas strain exhibited a range of degradation capabilities. Mineral salts medium (MSM) amended with glucose provided better environment for degradation with the highest degradation potential in strain SPR 13 followed by SPR 8 (71.9% and 69.0% respectively).

  4. Serotipificación y susceptibilidad antibacteriana de cepas de Pseudomonas aeruginosa aisladas de pacientes quemados infectados

    Directory of Open Access Journals (Sweden)

    Aniel Moya

    2003-06-01

    Full Text Available Se aislaron 11 cepas de Pseudomonas aeruginosa en 10 pacientes quemados que se encontraban hospitalizados y se les realizó tipificación serológica y antibiotipia para determinar los serotipos más frecuentes en este tipo de pacientes. Los serotipos de mayor frecuencia de aislamiento fueron el O4 y el O5. Observamos una marcada resistencia frente a los antibióticos: carbenicilina (81,8% y la azlocilina (72,7%.

  5. Effectiveness of halo-tolerant, auxin producing Pseudomonas and Rhizobium strains to improve osmotic stress tolerance in mung bean (Vigna radiata L.

    Directory of Open Access Journals (Sweden)

    Maqshoof Ahmad

    2013-12-01

    Full Text Available Halo-tolerant, auxin producing bacteria could be used to induce salt tolerance in plants. A number of Rhizobium and auxin producing rhizobacterial strains were assessed for their ability to tolerate salt stress by conducting osmoadaptation assay. The selected strains were further screened for their ability to induce osmotic stress tolerance in mung bean seedlings under salt-stressed axenic conditions in growth pouch/jar trials. Three most effective strains of Rhizobium and Pseudomonas containing ACC-deaminase were evaluated in combination, for their ability to induce osmotic stress tolerance in mung bean at original, 4, and 6 dS m-1 under axenic conditions. Results showed that sole inoculation of Rhizobium and Pseudomonas strains improved the total dry matter up to 1.4, and 1.9 fold, respectively, while the increase in salt tolerance index was improved up to 1.3 and 2.0 fold by the Rhizobium and Pseudomonas strains, respectively. However, up to 2.2 fold increase in total dry matter and salt tolerance index was observed due to combined inoculation of Rhizobium and Pseudomonas strains. So, combined application of Rhizobium and Pseudomonas strains could be explored as an effective strategy to induce osmotic stress tolerance in mung bean.

  6. INTERAKSI ANTARA Trichoderma Harzianum, Penicillium SP. DAN Pseudomonas SP. SERTA KAPASITAS ANTAGONISMENYA TERHADAP Phytophthora CapsicilN VITRO*[Interaction Among Trichoderma Harzianum, Penicillium SP., Pseudomonas SP. and Antagonism Capacities Against Phy

    OpenAIRE

    Suharna, Nandang

    2003-01-01

    A preliminary study has been done to know antagonism capacities of three isolates of Trichoderma harzianum, two isolates of Penicillium sp.and one isolate of Pseudomonas sp.against Phytophthora capsici in vitro and interaction among those six antagonists.The highest antagonism capacity possessed by Penicillium sp. KN1, respectively followed by Penicillium sp.KN2,Pseudomonas sp. GH1 and the three T. harzianum isolates. Except for those three T. harzianum isolates, the two Penicillium sp.isolat...

  7. Isolation of Pseudomonas cepacia in cystic fibrosis patient

    Directory of Open Access Journals (Sweden)

    Elizabeth de Andrade Marques

    1993-03-01

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

  8. A Phytoanticipin Derivative, Sodium Houttuyfonate, Induces in Vitro Synergistic Effects with Levofloxacin against Biofilm Formation by Pseudomonas aeruginosa

    Directory of Open Access Journals (Sweden)

    Jing Shao

    2012-09-01

    Full Text Available Antibiotic resistance has become the main deadly factor in infections, as bacteria can protect themselves by hiding in a self-constructed biofilm. Consequently, more attention is being paid to the search for “non-antibiotic drugs” to solve this problem. Phytoanticipins, the natural antibiotics from plants, could be a suitable alternative, but few works on this aspect have been reported. In this study, a preliminary study on the synergy between sodium houttuyfonate (SH and levofloxacin (LFX against the biofilm formation of Pseudomonas aeruginosa was performed. The minimal inhibitory concentrations (MIC of LFX and SH, anti-biofilm formation and synergistic effect on Pseudomonas aeruginosa, and quantification of alginate were determined by the microdilution method, crystal violet (CV assay, checkerboard method, and hydroxybiphenyl colorimetry. The biofilm morphology of Pseudomonas aeruginosa was observed by fluorescence microscope and scanning electric microscope (SEM. The results showed that: (i LFX and SH had an obvious synergistic effect against Pseudomonas aeruginosa with MIC values of 0.25 μg/mL and 128 μg/mL, respectively; (ii ½ × MIC SH combined with 2 × MIC LFX could suppress the biofilm formation of Pseudomonas aeruginosa effectively, with up to 73% inhibition; (iii the concentration of alginate decreased dramatically by a maximum of 92% after treatment with the combination of antibiotics; and (iv more dead cells by fluorescence microscope and more removal of extracellular polymeric structure (EPS by SEM were observed after the combined treatment of LFX and SH. Our experiments demonstrate the promising future of this potent antimicrobial agent against biofilm-associated infections.

  9. Detection of bla-IMP-1 and bla-IMP-2 Genes Among Metallo-β-lactamase-Producing Pseudomonas Aeruginosa Isolated from Burn Patients in Isfahan

    Directory of Open Access Journals (Sweden)

    M. Pourbabaee

    2016-02-01

    Full Text Available Background: Pseudomonas aeruginosa is a nosocomial pathogen which especially causes infections among burn patients. Carbapenems are extensively used for the treatment of infections caused by multidrug-resistant P. aeruginosa isolates. The emergence of carbapenemases producing isolates is an outcome of increased utilization of carbapenems. The aim of this study was to determine the bla-IMP-1 and bla-IMP-2 genes in metallo-β-lactamase (MBL -producing Pseudomonas aeruginosa isolated from burn patients in Isfahan. Material and Methods: A total of 150 P. aeruginosa were isolated from burn patients hospitalized in Imam-Mousakazem hospital in Isfahan. Antimicrobial susceptibility was determined using disk diffusion method according to the Clinical and Laboratory Standards Institute (CLSI guidelines. Double Disk Synergy Test (DDST was carried out for screening of MBL production in imipenem-resistant strains. PCR assays were used for detection of bla-IMP-1 and bla-IMP-2 genes among metallo-β-lactamase-producing Pseudomonas aeruginosa isolates. The purified PCR products were sequenced. Results: Of 150 Pseudomonas aeruginosa isolates, %100 identified as multi-drug resistant strains. The most resistance rates were seen against ciprofloxacin, tobromycin, meropenem and imipenem. All of 144 imipenem-resistant Pseudomonas aeruginosa isolates were MBL producing by DDST test. Twenty-nine (19.3% and 8(5.3% MBL producing Pseudomonas aeruginosa isolates harbored bla-IMP-1 and bla-IMP-2 genes respectively. Conclusions: According to results of this study high level resistance to imipenem and MBl genes carriage was seen among Pseudomonas aeruginosa isolated from burn patient infections in our region.

  10. Disinfection of Pseudomonas aeruginosa biofilm contaminated tube lumens with ultraviolet C light emitting diodes

    DEFF Research Database (Denmark)

    Bak, Jimmy; Ladefoged, Søren D; Tvede, Michael

    2010-01-01

    with biofilm was investigated. It was shown that UVC light propagation was possible through both Teflon and catheter tubes (silicone). The disinfection efficiency of the diodes was demonstrated on tubes contaminated artificially with a Pseudomonas aeruginosa biofilm. The tubes were connected to a flow system...... and biofilms were produced during a 3 day period. Tubes in lengths of 10 (Teflon, silicone) and 20 cm (Teflon) were contaminated. Tubes for control and for UVC treatment were contaminated in parallel. Biofilms were sampled from the total inner surface of the tubes. Colony counts on the control samples were...... in the range of 5 x 10(5)-1.3 x 10(9) CFU ml(-1), with disinfection rates in the range 96-100%. The applied UVC doses corresponded to treatment times between 15 and 300 min. Disinfection (100%) was obtained in 10 cm Teflon tubes exposed for 30 min (detection limit...

  11. Disinfection of Pseudomonas aeruginosa biofilm contaminated tube lumens with ultraviolet C light emitting diodes

    DEFF Research Database (Denmark)

    Bak, Jimmy; Ladefoged, S.D.; Tvede, M.

    2010-01-01

    with biofilm was investigated. It was shown that UVC light propagation was possible through both Teflon and catheter tubes ( silicone). The disinfection efficiency of the diodes was demonstrated on tubes contaminated artificially with a Pseudomonas aeruginosa biofilm. The tubes were connected to a flow system...... and biofilms were produced during a 3 day period. Tubes in lengths of 10 ( Teflon, silicone) and 20 cm ( Teflon) were contaminated. Tubes for control and for UVC treatment were contaminated in parallel. Biofilms were sampled from the total inner surface of the tubes. Colony counts on the control samples were...... in the range of 5 x 10(5)-1.3 x 10(9) CFU ml(-1), with disinfection rates in the range 96-100%. The applied UVC doses corresponded to treatment times between 15 and 300 min. Disinfection (100%) was obtained in 10 cm Teflon tubes exposed for 30 min (detection limit...

  12. The Enzymes of the Ammonia Assimilation in Pseudomonas aeruginosa

    NARCIS (Netherlands)

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

    1980-01-01

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

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

    African Journals Online (AJOL)

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

  14. Approach to Interfacial and Intramolecular Electron Transfer of the Diheme Protein Cytochrome c(4) Assembled on Au(111) Surfaces

    DEFF Research Database (Denmark)

    Chi, Qijin; Zhang, Jingdong; Taner, Arslan

    2010-01-01

    in homogeneous solution for which kinetic analysis clearly testifies to electrostatic cooperative effects but no intramolecular, interheme ET higher than 0.1-10 s(-1). This difference suggests a strong gating feature of the process. On the basis of the three-dimensional structure of P. stutzeri cyt c(4), gating...

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

    International Nuclear Information System (INIS)

    Liu, Junlin; Feng, Lei; Shi, Yawei; Feng, Wei

    2012-01-01

    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 C222 1 , 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 Å 3 Da −1 and approximately 50%, respectively

  16. The implication of Pseudomonas aeruginosa biofilms in infections

    DEFF Research Database (Denmark)

    Rybtke, Morten T; Jensen, Peter Østrup; Høiby, Niels

    2011-01-01

    Biofilm formation by bacteria is recognized as a major problem in chronic infections due to their recalcitrance against the immune defense and available antibiotic treatment schemes. The opportunistic pathogen Pseudomonas aeruginosa has drawn special attention in this regard due to its severity o...... treatment strategies where the underlying targets are less prone for resistance development as bacteria, in retrospect, have a unique ability to evade the actions of classic antibiotics.......Biofilm formation by bacteria is recognized as a major problem in chronic infections due to their recalcitrance against the immune defense and available antibiotic treatment schemes. The opportunistic pathogen Pseudomonas aeruginosa has drawn special attention in this regard due to its severity......-up of the extracellular matrix encasing the biofilm-associated bacteria as well as the elaborate signaling mechanisms employed by the bacterium enables it to withstand the continuous stresses imposed by the immune defense and administered antibiotics resulting in a state of chronic inflammation that damages the host...

  17. Characterization of siderophore produced by Pseudomonas syringae BAF.1 and its inhibitory effects on spore germination and mycelium morphology of Fusarium oxysporum.

    Science.gov (United States)

    Yu, Sumei; Teng, Chunying; Liang, Jinsong; Song, Tao; Dong, Liying; Bai, Xin; Jin, Yu; Qu, Juanjuan

    2017-11-01

    In this study, an antagonistic bacterium against Fusarium oxysporum was identified and designated as Pseudomonas syringae strain BAF.1 on the basis of 16S rDNA sequence analysis and physiological-biochemical characteristics. It produced catechol-species siderophore at a molecular weight of 488.59 Da and a maximum amount of 55.27 μg/ml with glucose as a carbon source and asparagine as a nitrogen source at a C/N ratio of 10:1, 30°C and pH 7. The siderophore exhibited prominent antagonistic activity against Fusarium oxysporum with a maximum inhibition rate of 95.24% and had also suppressive effects on other kinds of 11 phytopathogenic fungi in the absence of FeCl 3 ·6H 2 O. Spore germination was completely inhibited by 50 μl of the siderophorecontaining solution, and the ultrastructures of mycelia and spores were also considerably suppressed by siderophore treatment as established by electron microscopy observation. These results indicate that the siderophore produced by Pseudomonas syringae BAF.1 could be potentially used for biocontrol of pathogenic Fusarium oxysporum.

  18. Diversity of Aquatic Pseudomonas Species and Their Activity against the Fish Pathogenic Oomycete Saprolegnia.

    Directory of Open Access Journals (Sweden)

    Yiying Liu

    Full Text Available Emerging fungal and oomycete pathogens are increasingly threatening animals and plants globally. Amongst oomycetes, Saprolegnia species adversely affect wild and cultivated populations of amphibians and fish, leading to substantial reductions in biodiversity and food productivity. With the ban of several chemical control measures, new sustainable methods are needed to mitigate Saprolegnia infections in aquaculture. Here, PhyloChip-based community analyses showed that the Pseudomonadales, particularly Pseudomonas species, represent one of the largest bacterial orders associated with salmon eggs from a commercial hatchery. Among the Pseudomonas species isolated from salmon eggs, significantly more biosurfactant producers were retrieved from healthy salmon eggs than from Saprolegnia-infected eggs. Subsequent in vivo activity bioassays showed that Pseudomonas isolate H6 significantly reduced salmon egg mortality caused by Saprolegnia diclina. Live colony mass spectrometry showed that strain H6 produces a viscosin-like lipopeptide surfactant. This biosurfactant inhibited growth of Saprolegnia in vitro, but no significant protection of salmon eggs against Saprolegniosis was observed. These results indicate that live inocula of aquatic Pseudomonas strains, instead of their bioactive compound, can provide new (microbiological and sustainable means to mitigate oomycete diseases in aquaculture.

  19. Phylogenomics of 2,4-Diacetylphloroglucinol-Producing Pseudomonas and Novel Antiglycation Endophytes from Piper auritum.

    Science.gov (United States)

    Gutiérrez-García, Karina; Neira-González, Adriana; Pérez-Gutiérrez, Rosa Martha; Granados-Ramírez, Giovana; Zarraga, Ramon; Wrobel, Kazimierz; Barona-Gómez, Francisco; Flores-Cotera, Luis B

    2017-07-28

    2,4-Diacetylphloroglucinol (DAPG) (1) is a phenolic polyketide produced by some plant-associated Pseudomonas species, with many biological activities and ecological functions. Here, we aimed at reconstructing the natural history of DAPG using phylogenomics focused at its biosynthetic gene cluster or phl genes. In addition to around 1500 publically available genomes, we obtained and analyzed the sequences of nine novel Pseudomonas endophytes isolated from the antidiabetic medicinal plant Piper auritum. We found that 29 organisms belonging to six Pseudomonas species contain the phl genes at different frequencies depending on the species. The evolution of the phl genes was then reconstructed, leading to at least two clades postulated to correlate with the known chemical diversity surrounding DAPG biosynthesis. Moreover, two of the newly obtained Pseudomonas endophytes with high antiglycation activity were shown to exert their inhibitory activity against the formation of advanced glycation end-products via DAPG and related congeners. Its isomer, 5-hydroxyferulic acid (2), detected during bioactivity-guided fractionation, together with other DAPG congeners, were found to enhance the detected inhibitory activity. This report provides evidence of a link between the evolution and chemical diversity of DAPG and congeners.

  20. Diversity of Aquatic Pseudomonas Species and Their Activity against the Fish Pathogenic Oomycete Saprolegnia

    Science.gov (United States)

    Liu, Yiying; Rzeszutek, Elzbieta; van der Voort, Menno; Wu, Cheng-Hsuan; Thoen, Even; Skaar, Ida; Bulone, Vincent; Dorrestein, Pieter C.; Raaijmakers, Jos M.; de Bruijn, Irene

    2015-01-01

    Emerging fungal and oomycete pathogens are increasingly threatening animals and plants globally. Amongst oomycetes, Saprolegnia species adversely affect wild and cultivated populations of amphibians and fish, leading to substantial reductions in biodiversity and food productivity. With the ban of several chemical control measures, new sustainable methods are needed to mitigate Saprolegnia infections in aquaculture. Here, PhyloChip-based community analyses showed that the Pseudomonadales, particularly Pseudomonas species, represent one of the largest bacterial orders associated with salmon eggs from a commercial hatchery. Among the Pseudomonas species isolated from salmon eggs, significantly more biosurfactant producers were retrieved from healthy salmon eggs than from Saprolegnia-infected eggs. Subsequent in vivo activity bioassays showed that Pseudomonas isolate H6 significantly reduced salmon egg mortality caused by Saprolegnia diclina. Live colony mass spectrometry showed that strain H6 produces a viscosin-like lipopeptide surfactant. This biosurfactant inhibited growth of Saprolegnia in vitro, but no significant protection of salmon eggs against Saprolegniosis was observed. These results indicate that live inocula of aquatic Pseudomonas strains, instead of their bioactive compound, can provide new (micro)biological and sustainable means to mitigate oomycete diseases in aquaculture. PMID:26317985

  1. Crystal structure of secretory protein Hcp3 from Pseudomonas aeruginosa

    OpenAIRE

    Osipiuk, Jerzy; Xu, Xiaohui; Cui, Hong; Savchenko, Alexei; Edwards, Aled; Joachimiak, Andrzej

    2011-01-01

    The Type VI secretion pathway transports proteins across the cell envelope of Gram-negative bacteria. Pseudomonas aeruginosa, an opportunistic Gram-negative bacterial pathogen infecting humans, uses the type VI secretion pathway to export specific effector proteins crucial for its pathogenesis. The HSI-I virulence locus encodes for several proteins that has been proposed to participate in protein transport including the Hcp1 protein, which forms hexameric rings that assemble into nanotubes in...

  2. Novel Multiscale Modeling Tool Applied to Pseudomonas aeruginosa Biofilm Formation

    OpenAIRE

    Biggs, Matthew B.; Papin, Jason A.

    2013-01-01

    Multiscale modeling is used to represent biological systems with increasing frequency and success. Multiscale models are often hybrids of different modeling frameworks and programming languages. We present the MATLAB-NetLogo extension (MatNet) as a novel tool for multiscale modeling. We demonstrate the utility of the tool with a multiscale model of Pseudomonas aeruginosa biofilm formation that incorporates both an agent-based model (ABM) and constraint-based metabolic modeling. The hybrid mod...

  3. Effects of PslG on the surface movement of Pseudomonas aeruginosa.

    Science.gov (United States)

    Zhang, Jingchao; He, Jing; Zhai, Chunhui; Ma, Luyan Z; Gu, Lichuan; Zhao, Kun

    2018-05-04

    PslG attracted a lot of attention recently due to its great potential abilities in inhibiting biofilms of Pseudomonas aeruginosa However, how PslG affects biofilm development still remains largely unexplored. Here, we focused on the surface motility of bacterial cells, which is critical for biofilm development. We studied the effect of PslG on bacterial surface movement in early biofilm development at a single-cell resolution by using a high-throughput bacterial tracking technique. The results showed that compared with no exogenous PslG addition, when PslG was added to the medium, bacterial surface movement was significantly faster by 4 ∼ 5 times, and was in a more random way with no clear preferred direction. A further study revealed that the fraction of walking mode increased when PslG was added, which then resulted in an elevated average speed. The differences of motility due to PslG addition led to a clear distinction in patterns of bacterial surface movement, and retarded microcolony formation greatly. Our results provide insight into developing new PslG-based biofilm-control techniques. IMPORTANCE Biofilms of Pseudomonas aeruginosa are a major cause for hospital-acquired infections. They are notoriously difficult to eradicate and pose serious health hazard to our human society. So finding new ways to control biofilms are urgently needed. Recent work on PslG showed that PslG might be a good candidate for inhibiting/disassembling biofilms of Pseudomonas aeruginosa through Psl-based regulation. However, to fully explore PslG functions in biofilm-control, a better understanding of PslG-Psl interactions is needed. Toward this end, we examined the effect of PslG on the surface movement of Pseudomonas aeruginosa in this work. The significance of our work is in greatly enhancing our understanding of the inhibiting mechanism of PslG on biofilms by providing a detailed picture of bacterial surface movement at a single-cell level, which will allow a full understanding

  4. Assessment of Risk Factors, Treatment and Hospital Stay in Complicated Urinary Tract Infections in Men Caused by Pseudomonas: A Case-Control Study

    Directory of Open Access Journals (Sweden)

    Hasan Selçuk Özger

    2017-06-01

    Full Text Available Objective: It is known that Pseudomonas has been isolated more frequently in health care-related urinary tract infections (UTIs. It was aimed to determine the risk factors and empiric therapies due to antibiotic resistance in Pseudomonas-related male UTIs, and assess the effect of Pseudomonas isolation on treatment and length of hospital stay. Materials and Methods: The study was conducted between January 2011 and January 2013 with 228 male health care-related complicated UTI patients hospitalized in the Urology and Infectious Diseases Inpatient Clinics at Gazi University Faculty of Medicine. Three hundred UTI attacks in 228 patients were evaluated retrospectively with regard to agents. Results: Pseudomonas was isolated in 37 of 300 complicated UTI attacks in 228 male patients. Nephrolithiasis, recurrent UTI and internal urinary catheterization were determined as the risk factors for Pseudomonas related with health care-related UTI. It was understood that nephrolithiasis increased Pseudomonas isolated UTI risk 3.5 fold and recurrent UTI increased the risk 8.9 fold. The antibiotic resistance of Pseudomonas was higher than other agents. Pseudomonas related UTIs prolonged the duration of hospital stay and antibiotic treatment. Conclusion: In the presence of nephrolithiasis, recurrent UTI and internal urinary catheterization, drugs against Pseudomonas would be appropriate empiric treatment for health care-related complicated UTI. Ciprofloxacin use should be restricted when local antibiotic resistance, which leads empiric treatment, is taken into consideration. Increases in hospital stay and antibiotic treatment duration were thought to be associated with recurrent infection frequency and high antibiotics resistance in Pseudomonas related UTIs.

  5. Candidate nematicidal proteins in a new Pseudomonas veronii isolate identified by its antagonistic properties against Xiphinema index.

    Science.gov (United States)

    Canchignia, Hayron; Altimira, Fabiola; Montes, Christian; Sánchez, Evelyn; Tapia, Eduardo; Miccono, María; Espinoza, Daniel; Aguirre, Carlos; Seeger, Michael; Prieto, Humberto

    2017-03-17

    The nematode Xiphinema index affects grape vines and transmits important viruses associated with fanleaf degeneration. Pseudomonas spp. are an extensive bacterial group in which important biodegradation and/or biocontrol properties can occur for several strains in the group. The aim of this study was to identify new Pseudomonas isolates with antagonist activity against X. index. Forty bacterial isolates were obtained from soil and root samples from Chilean vineyards. Thirteen new fluorescent pseudomonads were found and assessed for their antagonistic capability. The nematicide Pseudomonas protegens CHA0 was used as a control. Challenges of nematode individuals in King's B semi-solid agar Petri dishes facilitated the identification of the Pseudomonas veronii isolate R4, as determined by a 16S rRNA sequence comparison. This isolate was as effective as CHA0 as an antagonist of X. index, although it had a different lethality kinetic. Milk-induced R4 cultures exhibited protease and lipase activities in cell supernatants using both gelatin/tributyrin Petri dish assays and zymograms. Three proteins with these activities were isolated and subjected to mass spectrometry. Amino acid partial sequences enabled the identification of a 49-kDa protease similar to metalloprotease AprA and two lipases of 50 kDa and 69 kDa similar to LipA and ExoU, respectively. Electron microscopy analyses of challenged nematodes revealed degraded cuticle after R4 supernatant treatment. These results represent a new and unexplored property in this species associated with the presence of secretable lipases and protease, similar to characterized enzymes present in biocontrol pseudomonads.

  6. Phospholipids and protein adaptation of Pseudomonas sp. to the xenoestrogen tributyltin chloride (TBT).

    Science.gov (United States)

    Bernat, Przemysław; Siewiera, Paulina; Soboń, Adrian; Długoński, Jerzy

    2014-09-01

    A tributyltin (TBT)-resistant strain of Pseudomonas sp. isolated from an overworked car filter was tested for its adaptation to TBT. The isolate was checked for organotin degradation ability, as well as membrane lipid and cellular protein composition in the presence of TBT. The phospholipid profiles of bacteria, grown with and without increased amounts of TBT, were characterized using liquid chromatography/electrospray ionization/mass spectrometry. The strain reacted to the biocide by changing the composition of its phospholipids. TBT induced a twofold decline in the amounts of many molecular species of phosphatidylglycerol and an increase in the levels of phosphatidic acid (by 58%) and phosphatidylethanolamine (by 70%). An increase in the degree of saturation of phospholipid fatty acids of TBT exposed Pseudomonas sp. was observed. These changes in the phospholipid composition and concentration reflect the mechanisms which support optimal lipid ordering in the presence of toxic xenobiotic. In the presence of TBT the abundances of 16 proteins, including TonB-dependent receptors, porins and peroxidases were modified, which could indicate a contribution of some enzymes to TBT resistance.

  7. Análisis de las polihidroxialcanoato sintasas (PhaC1 y PhaC2 en una cepa de Pseudomonas fluorescens IBUN S1602, aislada en suelos colombianos

    Directory of Open Access Journals (Sweden)

    Julieth Serrano Riaño

    2011-07-01

    Full Text Available Título en ingles: Analysis of polyhydroxyalkanoate synthases (PhaC1 and PhaC2 in a strain of Pseudomonas fluorescens   IBUN S1602 isolated from Colombian soil. Resumen La cepa Pseudomonas fluorescens IBUN S1602 conforma el grupo de aislamientos provenientes de suelos colombianos de caña de azúcar, que acumula polihidrioxialcanoato (PHA, fue seleccionada como promisoria para escalamiento comercial por tener afinidad por sustratos alternativos y económicos como el glicerol, aceites usados, suero de leche, entre otros. Dada la importancia de la enzima sintasa en la síntesis de los PHAs, en el presente trabajo se realizó el análisis molecular de los genes phaC1 y phaC2 que codifican las enzimas sintasas tipo II (PhaC1 y PhaC2. Para la obtención de los amplímeros requeridos en la secuenciación, se utilizó la técnica de PCR bajo condiciones estandarizadas para iniciadores diseñados reportados en las bases de datos. Se identificaron dos fragmentos de 1680 pb y 1683 pb correspondientes a  phaC1 y phaC2. El análisis comparativo de las secuencias proteicas resultantes de estos genes demuestra que la sintasa  IBUN S1602 contiene la región α/β hidrolasa y 8 residuos de aminoácidos conservados, que son características de las sintasas examinadas a nivel mundial. Se analizó la estructura enzimática a nivel primario y se predijo la secundaria. Se concluyó que  las sintasas de la cepa Pseudomonas fluorescens IBUN S1602 presentan alta homología con las sintasas tipo II  que se reportan para Pseudomonas. Los resultados obtenidos contribuyen al entendimiento básico de la biosíntesis de PHA,  la cual permitirá, en un futuro, el aumento de la calidad de PHA debida a la modulación del nivel de sintasa que se exprese en un organismo recombinante, con el fin de variar el peso molecular del biopolímero, propiedad esencial en el estudio de aplicaciones industriales.   Palabras clave: polihidroxialcanoatos, PHA sintasa, bioinform

  8. Pseudomonas fluorescens ATCC 13525 Containing an Artificial Oxalate Operon and Vitreoscilla Hemoglobin Secretes Oxalic Acid and Solubilizes Rock Phosphate in Acidic Alfisols

    OpenAIRE

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

    2014-01-01

    Oxalate secretion was achieved in Pseudomonas fluorescens ATCC 13525 by incorporation of genes encoding Aspergillus niger oxaloacetate acetyl hydrolase (oah), Fomitopsis plaustris oxalate transporter (FpOAR) and Vitreoscilla hemoglobin (vgb) in various combinations. Pf (pKCN2) transformant containing oah alone accumulated 19 mM oxalic acid intracellularly but secreted 1.2 mM. However, in the presence of an artificial oxalate operon containing oah and FpOAR genes in plasmid pKCN4, Pf (pKCN4) s...

  9. Characterization of initial events in bacterial surface colonization by two Pseudomonas species using image analysis.

    Science.gov (United States)

    Mueller, R F; Characklis, W G; Jones, W L; Sears, J T

    1992-05-01

    The processes leading to bacterial colonization on solid-water interfaces are adsorption, desorption, growth, and erosion. These processes have been measured individually in situ in a flowing system in real time using image analysis. Four different substrata (copper, silicon, 316 stainless-steel and glass) and 2 different bacterial species (Pseudomonas aeruginosa and Pseudomonas fluorescens) were used in the experiments. The flow was laminar (Re = 1.4) and the shear stress was kept constant during all experiments at 0.75 N m(-2). The surface roughness varied among the substrata from 0.002 microm (for silicon) to 0.015 microm (for copper). Surface free energies varied from 25.1 dynes cm(-1) for silicon to 31.2 dynes cm(-1) for copper. Cell curface hydrophobicity, reported as hydrocarbon partitioning values, ranged from 0.67 for Ps. fluorescens to 0.97 for Ps. aeruginosa.The adsorption rate coefficient varied by as much as a factor of 10 among the combinations of bacterial strain and substratum material, and was positively correlated with surface free energy, the surface roughness of the substratum, and the hydrophobicity of the cells. The probability of desorption decreased with increasing surface free energy and surface roughness of the substratum. Cell growth was inhibited on copper, but replication of cells overlying an initial cell layer was observed with increased exposure time to the cell-containing bulk water. A mathematical model describing cell accumulation on a substratum is presented.

  10. Effective Biosurfactants Production by Pseudomonas aeruginosa and its Efficacy on Different Oils

    Directory of Open Access Journals (Sweden)

    Sarita Kumari

    2010-07-01

    Full Text Available A rhamnolipid producing bacterium, Pseudomonas aeruginosa was isolated from contaminated soil with oily wastes. The Pseudomonas aeruginosa grown with glucose and corn oil as a carbon source produced bio-surfactant. This biosurfactant was purified by procedures that included chloroform-ethanol extraction and 0.05M bicarbonate treatments. The active compound was identified as rhamnolipid by using thin layer chromatography. The emulsification activity of bio-surfactant, the coconut oil responded better than the olive oil, groundnut oil and sunflower oil and gave a maximum level of 1 cm.

  11. Coinfection pulmonaire par pneumocystis jirovecii et pseudomonas aeruginosa au cours du SIDA: à propos de deux cas

    Science.gov (United States)

    Mamoudou, Savadogo; Bellaud, Guillaume; Ana, Canestri; Gilles, Pialoux

    2015-01-01

    Rapporter deux cas cliniques de coinfections pulmonaires par Pneumocystis jirovecii et par Pseudomonas aeruginosa chez des patients vivant avec le VIH. Les deux patients étaient âgés respectivement de 32 ans et 46 ans. Un patient a été pris en charge à l'hôpital Yalgado Ouédraogo de Ouagadougou au Burkina Faso et l'autre a été pris en charge à l'hôpital Ténon de Paris, en France. Les deux souffraient de pneumopathie confirmée à la radiographie et à la tomodensitométrie. L'un des patients était sévèrement immuno déprimé, contrairement à l'autre. L'examen bactériologique dans les crachats avait permis d'isoler Pseudomonas aeruginosa et Pneumocystis jirovecii chez les deux patients. Sous traitement, l’évolution a été favorable. Les coinfections morbides sont relativement fréquentes chez les patients vivant avec le VIH. Devant une symptomatologie respiratoire du sujet vivant avec le VIH, il faut savoir rechercher en plus du Bacille de Koch, Pneumocystis jirovecii et Pseudomonas aeruginosa par un lavage broncho alvéolaire. PMID:26516396

  12. Corneal Biofilms: From Planktonic to Microcolony Formation in an Experimental Keratitis Infection with Pseudomonas Aeruginosa.

    Science.gov (United States)

    Saraswathi, Padmanabhan; Beuerman, Roger W

    2015-10-01

    Microbial biofilms commonly comprise part of the infectious scenario, complicating the therapeutic approach. The purpose of this study was to determine in a mouse model of corneal infection if mature biofilms formed and to visualize the stages of biofilm formation. A bacterial keratitis model was established using Pseudomonas aeruginosa ATCC 9027 (1 × 10(8) CFU/ml) to infect the cornea of C57BL/6 black mouse. Eyes were examined post-infection (PI) on days 1, 2, 3, 5, and 7, and imaged by slit lamp microscopy, and light, confocal, and electron microscopy to identify the stages of biofilm formation and the time of appearance. On PI day 1, Gram staining showed rod-shaped bacteria adherent on the corneal surface. On PI days 2 and 3, bacteria were seen within webs of extracellular polymeric substance (EPS) and glycocalyx secretion, imaged by confocal microscopy. Scanning electron microscopy demonstrated microcolonies of active infectious cells bound with thick fibrous material. Transmission electron microscopy substantiated the formation of classical biofilm architecture with P. aeruginosa densely packed within the extracellular polymeric substances on PI days 5 and 7. Direct visual evidence showed that biofilms routinely developed on the biotic surface of the mouse cornea. The mouse model can be used to develop new approaches to deal therapeutically with biofilms in corneal infections. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  13. Two draft genome sequences of Pseudomonas jessenii strains isolated from a copper contaminated site in Denmark

    DEFF Research Database (Denmark)

    Qin, Yanan; Wang, Dan; Brandt, Kristian Koefoed

    2016-01-01

    Pseudomonas jessenii C2 and Pseudomonas jessenii H16 were isolated from low-Cu and high-Cu industrially contaminated soil, respectively. P. jessenii H16 displayed significant resistance to copper when compared to P. jessenii C2. Here we describe genome sequences and interesting features of these ......Pseudomonas jessenii C2 and Pseudomonas jessenii H16 were isolated from low-Cu and high-Cu industrially contaminated soil, respectively. P. jessenii H16 displayed significant resistance to copper when compared to P. jessenii C2. Here we describe genome sequences and interesting features...... of these two strains. The genome of P. jessenii C2 comprised 6,420,113 bp, with 5814 protein-coding genes and 67 RNA genes. P. jessenii H16 comprised 6,807,788 bp, with 5995 protein-coding genes and 70 RNA genes. Of special interest was a specific adaptation to this harsh copper-contaminated environment as P....... jessenii H16 contained a novel putative copper resistance genomic island (GI) of around 50,000 bp....

  14. Assessment of Pseudomonas aeruginosa N5,N10-methylenetetrahydrofolate dehydrogenase-cyclohydrolase as a potential antibacterial drug target.

    Directory of Open Access Journals (Sweden)

    Thomas C Eadsforth

    Full Text Available The bifunctional enzyme methylenetetrahydrofolate dehydrogenase - cyclohydrolase (FolD is identified as a potential drug target in Gram-negative bacteria, in particular the troublesome Pseudomonas aeruginosa. In order to provide a comprehensive and realistic assessment of the potential of this target for drug discovery we generated a highly efficient recombinant protein production system and purification protocol, characterized the enzyme, carried out screening of two commercial compound libraries by differential scanning fluorimetry, developed a high-throughput enzyme assay and prosecuted a screening campaign against almost 80,000 compounds. The crystal structure of P. aeruginosa FolD was determined at 2.2 Å resolution and provided a template for an assessment of druggability and for modelling of ligand complexes as well as for comparisons with the human enzyme. New FolD inhibitors were identified and characterized but the weak levels of enzyme inhibition suggest that these compounds are not optimal starting points for future development. Furthermore, the close similarity of the bacterial and human enzyme structures suggest that selective inhibition might be difficult to attain. In conclusion, although the preliminary biological data indicates that FolD represents a valuable target for the development of new antibacterial drugs, indeed spurred us to investigate it, our screening results and structural data suggest that this would be a difficult enzyme to target with respect to developing the appropriate lead molecules required to underpin a serious drug discovery effort.

  15. Pseudomonas sp. LMTK32 production in modified media for pelleting seeds of maca (Lepidium meyenii Walp.

    Directory of Open Access Journals (Sweden)

    Martin Guerra Lopez

    2018-05-01

    Full Text Available Biomass of Pseudomonas sp. LMTK32 was produced from modification of culture media Yeast Extract Mannitol Broth (YEMB with the aim of increasing the number of viable cells with the ability to promote the germination of maca seeds pelleted with the bacteria and reduce production costs. In the optimization process, the yeast extract and mannitol components of the LMC culture media were replaced by commercial sources of sucrose and glutamate, whose concentrations were determined in flasks by statistical design from Box-Behnken; in addition, the effect of the inoculum percentage on the time of biomass production was determined. Subsequently, it was determined at the bioreactor level that 28.57 h-1 was the adequate value of the volumetric oxygen transfer coefficient (kLa at 600 rpm, producing 1.28 x 10 11 CFU / mL. In the LMC M1 modified media, using 12.06 g / L-1 of sucrose, 11.50 g / L-1 of sodium glutamate and 10.9% of inoculant obtained 15x108 CFU / mL, increasing in 48% the number of viable cells with respect to the YEMB control treatment (7.8x10 8 CFU / mL. At the in vitro level, the pelleting of maca seeds with Pseudomonas sp. LMTK32 produced in bioreactor and in the modified media M1 favored its germination. From commercial organic substrates, efficient bacterial inoculants can be produced in the development of maca crops, without altering their ability to promote plant growth.

  16. Study of anti mutagenic and mutagenic effect of different chemicals on clinically isolated strains of pseudomonas aeruginosa

    International Nuclear Information System (INIS)

    Qureshi, A.M.; Durrani, F.; Janjua, M.

    1994-01-01

    This project was undertaken to study the effect of twelve different compounds to test their anti mutagenic and mutagenic activity against clinically isolated strains of Pseudomonas aeruginosa. The effect of these compounds was estimated by counting the number of rifampicin resistant colonies growing in a particular time in a compound. The results were interpreted by plotting graphs between 10g N/NO (Rif R Colonies/ ml) and time to estimate the forward mutation rat. The results revealed that acridine, Basic fuchsin, Caffeine, cycloheximide, Ethidium bromide and Histidine probably have an anti mutagenic effect, while Cysteine, folic acid, Ethyl methane, suplphonate, Manganous Chloride and N-nitrosodietylamine acted as mutagen. Ecoli was used as control through out the study. (author)

  17. New strategies for genetic engineering Pseudomonas syringae using recombination

    Science.gov (United States)

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

  18. Photoreactivation of Pseudomonas cepacia after ultraviolet exposure: a potential source of contamination in ultraviolet-treated waters

    International Nuclear Information System (INIS)

    Carson, L.A.; Petersen, N.J.

    1975-01-01

    Cells of a naturally occurring strain of Pseudomonas cepacia grown in distilled water were exposed to ultraviolet radiation. Irradiated samples incubated on membrane filters or in fluid recovery media in the absence of light showed no evidence of dark repair mechanisms. When samples were exposed to fluorescent light ranging from 50 to 950 foot candles (538 to 10,222 lux) of illumination, apparent photo-induced repair of ultraviolet injury resulted in 1- to 4-log increases in viable cells recovered

  19. Pseudomonas syringae evades host immunity by degrading flagellin monomers with alkaline protease AprA

    NARCIS (Netherlands)

    Pel, Michiel J C; van Dijken, Anja J H; Bardoel, Bart W; Seidl, Michael F; van der Ent, Sjoerd; van Strijp, Jos A G; Pieterse, Corné M J

    Bacterial flagellin molecules are strong inducers of innate immune responses in both mammals and plants. The opportunistic pathogen Pseudomonas aeruginosa secretes an alkaline protease called AprA that degrades flagellin monomers. Here, we show that AprA is widespread among a wide variety of

  20. Pseudomonas syringae evades host Immunity by degrading flagellin monomers with alkaline protease AprA

    NARCIS (Netherlands)

    Pel, M.J.C.; Van Dijken, A.J.H.; Bardoel, B.W.; Seidl, M.F; Van der Ent, S.; Van Strijp, J.A.G.

    2014-01-01

    Bacterial flagellin molecules are strong inducers of innate immune responses in both mammals and plants. The opportunistic pathogen Pseudomonas aeruginosa secretes an alkaline protease called AprA that degrades flagellin monomers. Here, we show that AprA is widespread among a wide variety of

  1. Molecular characterization of Pseudomonas syringae pv. tomato isolates from Tanzania

    DEFF Research Database (Denmark)

    Shenge, K.C.; Stephan, D.; Mabagala, R. B.

    2008-01-01

    Bacterial speck caused by Pseudomonas syringae pv. tomato is an emerging disease of tomato in Tanzania. Following reports of outbreaks of the disease in many locations in Tanzania, 56 isolates of P. syringae pv. tomato were collected from four tomato- producing areas and characterized using...

  2. OXIDATION OF BIPHENYL BY A MULTICOMPONENT ENZYME SYSTEM FROM PSEUDOMONAS SP. STRAIN LB400

    Science.gov (United States)

    Pseudomonas sp. strain LB400 grows on biphenyl as the sole carbon and energy source. This organism also cooxidizes several chlorinated biphenyl congeners. Biphenyl dioxygenase activity in cell extract required addition of NAD(P)H as an electron donor for the conversion of bipheny...

  3. Pseudomonas aeruginosa quorum-sensing signal molecules interfere with dendritic cell-induced T-cell proliferation

    DEFF Research Database (Denmark)

    Skindersø, Mette Elena; Zeuthen, Louise; Pedersen, Susanne Brix

    2009-01-01

    Pseudomonas aeruginosa releases a wide array of toxins and tissue-degrading enzymes. Production of these malicious virulence factors is controlled by interbacterial communication in a process known as quorum sensing. An increasing body of evidence reveals that the bacterial signal molecule N-(3-o...

  4. Adhesion of Pseudomonas aeruginosa to orthokeratology and alignment lenses.

    Science.gov (United States)

    Choo, Jennifer D; Holden, Brien A; Papas, Eric B; Willcox, Mark D P

    2009-02-01

    To determine whether contact lenses designed for orthokeratology (OK) are colonized by greater numbers of bacteria compared with standard (alignment fitted) design rigid gas permeable lenses before and after lens wear. Eighteen 1-year-old cats were randomly fitted with an OK lens in one eye and an alignment fitted (AF) lens in the other eye. Both lenses were made in the same diameter and central thickness and of the same material. Two separate wearing periods of 2 weeks and 6 weeks were used. After each wearing period, lenses were soaked in Pseudomonas aeruginosa (6294 or 6206) for 10 min. The lenses were then reinserted onto their respective corneas for a wearing period of 16 hours after which lenses were collected and remaining adhered bacteria quantified. Unworn control lenses were also soaked and bacteria enumerated for comparison. There were no significant differences in the number of bacteria adherent to unworn AF and OK lenses. Analysis of lenses after wear showed OK lenses retained significantly higher numbers of viable bacteria than AF lenses in all studies. OK lenses retain more bacteria than AF rigid gas permeable lenses after bacteria-loaded overnight lens wear. This may increase the risk for an infection in OK patients should suitable conditions be present. Specific education on the cleaning of OK lenses is essential.

  5. Engineering Pseudomonas for phenazine biosynthesis, regulation, and biotechnological applications: a review.

    Science.gov (United States)

    Bilal, Muhammad; Guo, Shuqi; Iqbal, Hafiz M N; Hu, Hongbo; Wang, Wei; Zhang, Xuehong

    2017-10-03

    Pseudomonas strains are increasingly attracting considerable attention as a valuable bacterial host both for basic and applied research. It has been considered as a promising candidate to produce a variety of bioactive secondary metabolites, particularly phenazines. Apart from the biotechnological perspective, these aromatic compounds have the notable potential to inhibit plant-pathogenic fungi and thus are useful in controlling plant diseases. Nevertheless, phenazines production is quite low by the wild-type strains that necessitated its yield improvement for large-scale agricultural applications. Metabolic engineering approaches with the advent of plentiful information provided by systems-level genomic and transcriptomic analyses enabled the development of new biological agents functioning as potential cell factories for producing the desired level of value-added bioproducts. This study presents an up-to-date overview of recombinant Pseudomonas strains as the preferred choice of host organisms for the biosynthesis of natural phenazines. The biosynthetic pathway and regulatory mechanism involved in the phenazine biosynthesis are comprehensively discussed. Finally, a summary of biological functionalities and biotechnological applications of the phenazines is also provided.

  6. Spatial distributions of Pseudomonas fluorescens colony variants in mixed-culture biofilms.

    Science.gov (United States)

    Workentine, Matthew L; Wang, Siyuan; Ceri, Howard; Turner, Raymond J

    2013-07-28

    The emergence of colony morphology variants in structured environments is being recognized as important to both niche specialization and stress tolerance. Pseudomonas fluorescens demonstrates diversity in both its natural environment, the rhizosphere, and in laboratory grown biofilms. Sub-populations of these variants within a biofilm have been suggested as important contributors to antimicrobial stress tolerance given their altered susceptibility to various agents. As such it is of interest to determine how these variants might be distributed in the biofilm environment. Here we present an analysis of the spatial distribution of Pseudomonas fluorescens colony morphology variants in mixed-culture biofilms with the wildtype phenotype. These findings reveal that two variant colony morphotypes demonstrate a significant growth advantage over the wildtype morphotype in the biofilm environment. The two variant morphotypes out-grew the wildtype across the entire biofilm and this occurred within 24 h and was maintained through to 96 h. This competitive advantage was not observed in homogeneous broth culture. The significant advantage that the variants demonstrate in biofilm colonization over the wildtype denotes the importance of this phenotype in structured environments.

  7. Best conditions for biodegradation of diesel oil by chemometric tools

    Directory of Open Access Journals (Sweden)

    Ewa Kaczorek

    2014-01-01

    Full Text Available Diesel oil biodegradation by different bacteria-yeast-rhamnolipids consortia was tested. Chromatographic analysis of post-biodegradation residue was completed with chemometric tools (ANOVA, and a novel ranking procedure based on the sum of ranking differences. These tools were used in the selection of the most effective systems. The best results of aliphatic fractions of diesel oil biodegradation were observed for a yeast consortia with Aeromonas hydrophila KR4. For these systems the positive effect of rhamnolipids on hydrocarbon biodegradation was observed. However, rhamnolipids addition did not always have a positive influence on the biodegradation process (e.g. in case of yeast consortia with Stenotrophomonas maltophila KR7. Moreover, particular differences in the degradation pattern were observed for lower and higher alkanes than in the case with C22. Normally, the best conditions for "lower" alkanes are Aeromonas hydrophila KR4 + emulsifier independently from yeasts and e.g. Pseudomonas stutzeri KR7 for C24 alkane.

  8. Best conditions for biodegradation of diesel oil by chemometric tools

    Science.gov (United States)

    Kaczorek, Ewa; Bielicka-Daszkiewicz, Katarzyna; Héberger, Károly; Kemény, Sándor; Olszanowski, Andrzej; Voelkel, Adam

    2014-01-01

    Diesel oil biodegradation by different bacteria-yeast-rhamnolipids consortia was tested. Chromatographic analysis of post-biodegradation residue was completed with chemometric tools (ANOVA, and a novel ranking procedure based on the sum of ranking differences). These tools were used in the selection of the most effective systems. The best results of aliphatic fractions of diesel oil biodegradation were observed for a yeast consortia with Aeromonas hydrophila KR4. For these systems the positive effect of rhamnolipids on hydrocarbon biodegradation was observed. However, rhamnolipids addition did not always have a positive influence on the biodegradation process (e.g. in case of yeast consortia with Stenotrophomonas maltophila KR7). Moreover, particular differences in the degradation pattern were observed for lower and higher alkanes than in the case with C22. Normally, the best conditions for “lower” alkanes are Aeromonas hydrophila KR4 + emulsifier independently from yeasts and e.g. Pseudomonas stutzeri KR7 for C24 alkane. PMID:24948922

  9. HOPM1 mediated disease resistance to Pseudomonas syringae in Arabidopsis

    Science.gov (United States)

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

    2011-11-15

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

  10. RpoN Modulates Carbapenem Tolerance in Pseudomonas aeruginosa through Pseudomonas Quinolone Signal and PqsE

    Science.gov (United States)

    Murakami, Keiji; Amoh, Takashi; Ono, Tsuneko; Miyake, Yoichiro

    2016-01-01

    The ability of Pseudomonas aeruginosa to rapidly modulate its response to antibiotic stress and persist in the presence of antibiotics is closely associated with the process of cell-to-cell signaling. The alternative sigma factor RpoN (σ54) is involved in the regulation of quorum sensing (QS) and plays an important role in the survival of stationary-phase cells in the presence of carbapenems. Here, we demonstrate that a ΔrpoN mutant grown in nutrient-rich medium has increased expression of pqsA, pqsH, and pqsR throughout growth, resulting in the increased production of the Pseudomonas quinolone signal (PQS). The link between pqsA and its role in carbapenem tolerance was studied using a ΔrpoN ΔpqsA mutant, in which the carbapenem-tolerant phenotype of the ΔrpoN mutant was abolished. In addition, we demonstrate that another mechanism leading to carbapenem tolerance in the ΔrpoN mutant is mediated through pqsE. Exogenously supplied PQS abolished the biapenem-sensitive phenotype of the ΔrpoN ΔpqsA mutant, and overexpression of pqsE failed to alter the susceptibility of the ΔrpoN ΔpqsA mutant to biapenem. The mutations in the ΔrpoN ΔrhlR mutant and the ΔrpoN ΔpqsH mutant led to susceptibility to biapenem. Comparison of the changes in the expression of the genes involved in QS in wild-type PAO1 with their expression in the ΔrpoN mutant and the ΔrpoN mutant-derived strains demonstrated the regulatory effect of RpoN on the transcript levels of rhlR, vqsR, and rpoS. The findings of this study demonstrate that RpoN negatively regulates the expression of PQS in nutrient-rich medium and provide evidence that RpoN interacts with pqsA, pqsE, pqsH, and rhlR in response to antibiotic stress. PMID:27431228

  11. Pseudomonas aeruginosa biofilms in cystic fibrosis

    DEFF Research Database (Denmark)

    Høiby, Niels; Ciofu, Oana; Bjarnsholt, Thomas

    2010-01-01

    The persistence of chronic Pseudomonas aeruginosa lung infections in cystic fibrosis (CF) patients is due to biofilm-growing mucoid (alginate-producing) strains. A biofilm is a structured consortium of bacteria, embedded in a self-produced polymer matrix consisting of polysaccharide, protein...... and DNA. In CF lungs, the polysaccharide alginate is the major part of the P. aeruginosa biofilm matrix. Bacterial biofilms cause chronic infections because they show increased tolerance to antibiotics and resist phagocytosis, as well as other components of the innate and the adaptive immune system....... As a consequence, a pronounced antibody response develops, leading to immune complex-mediated chronic inflammation, dominated by polymorphonuclear leukocytes. The chronic inflammation is the major cause of the lung tissue damage in CF. Biofilm growth in CF lungs is associated with an increased frequency...

  12. Effect of Indigenous Pseudomonas sp. and Bacillus sp. Strains on Yield and Main Chemical Growth Parameters of Radicchio

    Directory of Open Access Journals (Sweden)

    Stanojković-Sebić Aleksandra

    2018-03-01

    Full Text Available Pseudomonas sp. and Bacillus sp. belong to plant growth promoting rhizobacteria which are able to colonize the plants roots and stimulate growth. In this study, the effect of two indigenous plant growth promoting rhizobacterial strains Pseudomonas sp. Q4 and Bacillus sp. Q10 and their mixture (mix Q4+Q10 on content of the main chemical growth parameters (nitrogen, phosphorus, potassium, calcium and magnesium and the yield of dry biomass of radicchio (Cichorium spp. var. rossa di treviso aerial parts and root, was investigated. The study was carried out with stagnosol type of soil in pot experiments under semi-controlled conditions in the Institute of Soil Science (Belgrade, in the period from July to October in 2013. Phosphorus was determined by spectrophotometer, potassium - by flame emission photometry and total nitrogen and carbon - using elemental CNS analyzer, while calcium and magnesium were determined by AAS. The data on yield of both aerial parts and root dry biomass of radicchio showed that its treatment with Q4 and Q10 strains, as well as with their mixture, caused noticeably increase in this parameter in relation to the control, whereby the strain Q4 was more effective for aerial parts, while mix Q4+Q10 - for roots. The obtained data on the studied chemical parameters of radicchio root and aerial parts were in total accordance with their yield. Concluding, studied strains have a potential in promoting the biomass yield and main chemical growth parameters of both aerial parts and root of radicchio.

  13. Rapid identification of Pseudomonas aeruginosa by pulsed-field gel electrophoresis.

    Science.gov (United States)

    Selim, Samy; El Kholy, Iman; Hagagy, Nashwa; El Alfay, Sahar; Aziz, Mohamed Abdel

    2015-01-02

    Twenty clinical Pseudomonas aeruginosa isolates recovered from patients admitted to The General Hospital in Ismailia Governorate (Egypt) were examined in this study. We analysed P. aeruginosa ATCC 9027 (as a control strain) and 19 of the isolates after digestion with SpeI restriction endonuclease. After this we conducted a pulsed-field gel electrophoresis (PFGE) and typed the obtained 10 unique patterns, designated as A, A1, B, B1, C, C1, D, D1, E and F. We evaluated the genetic relatedness between all strains, based on ≥87% band identity. As a result, the isolates were grouped in the 10 clusters as follows: patterns A, A1, B, B1, C contained two strains each and patterns C1, D, D1, E contained a single strain each; the five remaining strains were closely related (genomic pattern F). One isolate belonged to antibiotype 'b'. The genotype patterns of the P. aeruginosa ATCC 9027 control strain and isolate no. 11 were closely related and had two different antibiotypes 'd' and 'c', respectively.

  14. Generalized Growth of Estuarine, Household and Clinical Isolates of Pseudomonas aeruginosa

    OpenAIRE

    Kelly E. Diaz; Susanna K. Remold; Ogochukwu Onyiri; Maura Bozeman; Peter A. Raymond; Paul E. Turner; Paul E. Turner

    2018-01-01

    Pseudomonas aeruginosa is an opportunistic pathogen of particular concern to immune-compromised people, such as cystic fibrosis patients and burn victims. These bacteria grow in built environments including hospitals and households, and in natural environments such as rivers and estuaries. However, there is conflicting evidence whether recent environments like the human lung and open ocean affect P. aeruginosa growth performance in alternate environments. We hypothesized that bacteria recentl...

  15. Inhibition of quorum sensing in Pseudomonas aeruginosa biofilm bacteria by a halogenated furanone compound

    DEFF Research Database (Denmark)

    Hentzer, Morten; Riedel, K.; Rasmussen, Thomas Bovbjerg

    2002-01-01

    Novel molecular tools have been constructed which allow for in situ detection of N-acyl homoserine lactone (AHL)-mediated quorum sensing in Pseudomonas aeruginosa biofilms. The reporter responds to AHL activation of LasR lay expression of an unstable version of the green-fluorescent protein (Gfp...

  16. Biofilm Formation Mechanisms of Pseudomonas aeruginosa Predicted via Genome-Scale Kinetic Models of Bacterial Metabolism

    Science.gov (United States)

    2016-03-15

    RESEARCH ARTICLE Biofilm Formation Mechanisms of Pseudomonas aeruginosa Predicted via Genome-Scale Kinetic Models of Bacterial Metabolism Francisco G...jaques.reifman.civ@mail.mil Abstract A hallmark of Pseudomonas aeruginosa is its ability to establish biofilm -based infections that are difficult to...eradicate. Biofilms are less susceptible to host inflammatory and immune responses and have higher antibiotic tolerance than free-living planktonic

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

    NARCIS (Netherlands)

    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

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

    African Journals Online (AJOL)

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

  19. Ecofriendly biodegradation and detoxification of Reactive Red 2 textile dye by newly isolated Pseudomonas sp. SUK1

    International Nuclear Information System (INIS)

    Kalyani, D.C.; Telke, A.A.; Dhanve, R.S.; Jadhav, J.P.

    2009-01-01

    The aim of this work is to evaluate textile dyes degradation by novel bacterial strain isolated from the waste disposal sites of local textile industries. Detailed taxonomic studies identified the organisms as Pseudomonas species and designated as strain Pseudomonas sp. SUK1. The isolate was able to decolorize sulfonated azo dye (Reactive Red 2) in a wide range (up to 5 g l -1 ), at temperature 30 deg. C, and pH range 6.2-7.5 in static condition. This isolate also showed decolorization of the media containing a mixture of dyes. Measurements of COD were done at regular intervals to have an idea of mineralization, showing 52% reduction in the COD within 24 h. Induction in the activity of lignin peroxidase and azoreductase was observed during decolorization of Reactive Red 2 in the batch culture, which represented their role in degradation. The biodegradation was monitored by UV-vis, IR spectroscopy, HPLC. The final product, 2-naphthol was characterized by GC-mass spectroscopy. The phytotoxicity study revealed the degradation of Reactive Red 2 into non-toxic product by Pseudomonas sp. SUK1

  20. Fast biodegradation of toxic bisphenol a by Pseudomonas aeruginosa NR.22 (Ps.NR.22) isolated from Malaysian local lake

    Science.gov (United States)

    Him, Nik Raikhan Nik; Zainuddin, Mohammad Fiqri; Basha, Anuar Zain Anuar

    2017-12-01

    The paper focused on microbial degradation of Bisphenol A (BPA) as a safe and fast method to reduce BPA contamination in water. BPA is found in waste water, sea water and home water pipeline and it is nondegradable pollutant. Biodegradation is suggested to be practical solution for large volume of BPA. Biodegradation plays an important role and the effect of low concentration significantly decreased the degradation rate. Pseudomonas aeruginosa NR.22 (Ps.NR.22) which has been isolated from a lake at Seksyen 2, Shah Alam, was used. In Malaysia, Ps.NR.22 isolation agar is used for the BPA degradation process. It was stained with Gram negative-rod shaped bacteria that confirmed to carry a 16S rRNA gene. BPA as a sole carbon has been tested at various concentrations. The research showed that BPA was degraded at 10, 20, 30, 40 and 50 ppm and the bacteria growth rate was excellent in 20 ppm BPA. Degradation of BPA was carried out for 9 hours to 18 hours and the maximum degradation was recorded at 9 hours. The value of the highest peak of growth at 540 nm was 2.0617 using 20 ppm BPA. This novel Pseudomonas aeruginosa NR.22 has great potential to be used in waste water treatment.

  1. Explore the full thick layer of corneal transplantation in the treatment of pseudomonas aeruginosa corneal ulcer infection

    Directory of Open Access Journals (Sweden)

    Xin Wang

    2015-02-01

    Full Text Available AIM: To explore the feasibility, safety and effect of the full-thickness lamellar keratoplasty for the treatment of pseudomonas aeruginosa corneal ulcer. METHODS: Based on a retrospective non-controlled study, 25 patients were given the full-thickness lamellar keratoplasty for clinical diagnosis of pseudomonas aeruginosa infection and corneal ulcer medication conventional anti-gram-negative bacteria. Routine follow-up were carried out at postoperative 1wk; 1, 3, 6, 12, 18mo to observe the situation of corneal epithelial healing, recurrent infection, immune rejection, graft transparency and best corrected visual acuity, etc. At the 6 and 12mo postoperative, corneal endothelial cell density was reexamined.RESULTS: No patients because of Descemet's membrane rupture underwent penetrating keratoplasty surgery: One only in cases of bacterial infection after 1mo, once again did not cultivate a culture of bacteria pseudomonas aeruginosa, and the remaining 24 cases average follow-up 14±6mo, corneal graft were transparent, the cure rate was 96%. At the sixth month after surgery, there were 16 cases of eye surgery best corrected visual acuity ≥4.5, of which 3 cases ≥4.8. At the sixth month after surgery, the average corneal endothelial cell density 2 425±278/mm2; At 12mo postoperatively, it was 2 257± 326/mm2.CONCLUSION: Full-thickness lamellar keratoplasty is an effective method of pseudomonas aeruginosa infection in the treatment of corneal ulcers, corneal drying material glycerol can be achieved by visual effects.

  2. Comparative genome and transcriptome analysis reveals distinctive surface characteristics and unique physiological potentials of Pseudomonas aeruginosa ATCC 27853

    KAUST Repository

    Cao, Huiluo; Lai, Yong; Bougouffa, Salim; Xu, Zeling; Yan, Aixin

    2017-01-01

    Pseudomonas aeruginosa ATCC 27853 was isolated from a hospital blood specimen in 1971 and has been widely used as a model strain to survey antibiotics susceptibilities, biofilm development, and metabolic activities of Pseudomonas spp.. Although four

  3. Alkaline cyanide degradation by Pseudomonas pseudoalcaligenes CECT5344 in a batch reactor. Influence of pH

    Energy Technology Data Exchange (ETDEWEB)

    Huertas, M.J., E-mail: mjhuertas@us.es [Instituto de Bioquimica Vegetal y Fotosintesis, CSIC-Universidad de Sevilla Avda Americo Vespucio, 49, 41092 Sevilla (Spain); Saez, L.P.; Roldan, M.D.; Luque-Almagro, V.M.; Martinez-Luque, M. [Departamento de Bioquimica y Biologia Molecular, Edificio Severo Ochoa, 1a Planta, Campus de Rabanales, Universidad de Cordoba, 14071 Cordoba (Spain); Blasco, R. [Departamento de Bioquimica y Biologia Molecular y Genetica, Facultad de Veterinaria, Universidad de Extremadura, 11071 Caceres (Spain); Castillo, F.; Moreno-Vivian, C. [Departamento de Bioquimica y Biologia Molecular, Edificio Severo Ochoa, 1a Planta, Campus de Rabanales, Universidad de Cordoba, 14071 Cordoba (Spain); Garcia-Garcia, I. [Departamento de Ingenieria Quimica, Edificio Marie Curie, Campus de Rabanales, Universidad de Cordoba, 14071 Cordoba (Spain)

    2010-07-15

    Water containing cyanide was biologically detoxified with the bacterial strain Pseudomonas pseudoalcaligenes CECT5344 in a batch reactor. Volatilization of toxic hydrogen cyanide (HCN) was avoided by using an alkaline medium for the treatment. The operational procedure was optimized to assess cyanide biodegradation at variable pH values and dissolved oxygen concentrations. Using an initial pH of 10 without subsequent adjustment allowed total cyanide to be consumed at a mean rate of approximately 2.81 mg CN{sup -} L{sup -1} O.D.{sup -1} h{sup -1}; however, these conditions posed a high risk of HCN formation. Cyanide consumption was found to be pH-dependent. Thus, no bacterial growth was observed with a controlled pH of 10; on the other hand, pH 9.5 allowed up to 2.31 mg CN{sup -} L{sup -1} O.D.{sup -1} h{sup -1} to be converted. The combination of a high pH and a low dissolved oxygen saturation (10%) minimized the release of HCN. This study contributes new basic knowledge about this biological treatment, which constitutes an effective alternative to available physico-chemical methods for the purification of wastewater containing cyanide or cyano-metal complexes.

  4. DEPENDENCE BETWEEN ACYLATION DEGREE AND SPECIFIC LYSIS ACTITIVY OF THE PSEUDOMONAS AERUGINOSA М6 BACTERIOPHAGE

    Directory of Open Access Journals (Sweden)

    Martynov A. V.

    2016-06-01

    Full Text Available Introduction. The purpose of this work is to study the influence of various degrees of protein’s acylation on lytic activity and other biological properties of Pseudomonas M6 bacteriophage. Materials and methods. The subject of the study were samples of the Pseudomonas O 12 bacteriophage, hereinafter named the M6 phage. Pure phage lines were obtained from individual standard-morphology phage plaques (plaque-forming units, or PFUs after ten passes over the indicator strain. In subsequent experiments, M6 phage samples were selected that had a sufficient level of purity (homogeneous in the morphology of virions that inactivated the homologic antiphage serum by no less than 99.0% and the heterologic antibacterial serum by no more than 1%, and a titer no lower than 10 PFU per ml (PFU/ml. Titration of the phages was conducted using the standard bilayer agar. The crude protein content in the phage suspensions was determined using the spectroscopic method (at 280 and 260 nm. Succinylation of the phage samples was conducted according to the method developed by T.J. Molenaar. The phage’s lytic activity spectrum was determined through spot tests on 224 strains of the Pseudomonas genus and 106 strains of other genera (correspondingly, of strains Enterobacter -40, Escherichia -10, Citrobacter -8, Hafnia -7, Serratia -6, Shigella -10, Salmonella -8, Proteus -7 through the use of a phage suspension containing 10 5 - 10 6 PFU/ml. (This concentration of infectious phage corpuscles corresponds with the critical distribution of the M6 phage. The results of the research were subjected to statistical processing using single-factor dispersion analysis. Results and discussion. One hundred percent phage protein acylation leads to a loss of adsorption ability on sensitive cells and is accompanied by a significant (more than 103 times decrease in the level of specific lytic activity in the phage preparations. The succinylation type being studied does not cause

  5. Degradation and metabolism of synthetic plastics and associated products by Pseudomonas sp.: capabilities and challenges.

    Science.gov (United States)

    Wilkes, R A; Aristilde, L

    2017-09-01

    Synthetic plastics, which are widely present in materials of everyday use, are ubiquitous and slowly-degrading polymers in environmental wastes. Of special interest are the capabilities of microorganisms to accelerate their degradation. Members of the metabolically diverse genus Pseudomonas are of particular interest due to their capabilities to degrade and metabolize synthetic plastics. Pseudomonas species isolated from environmental matrices have been identified to degrade polyethylene, polypropylene, polyvinyl chloride, polystyrene, polyurethane, polyethylene terephthalate, polyethylene succinate, polyethylene glycol and polyvinyl alcohol at varying degrees of efficiency. Here, we present a review of the current knowledge on the factors that control the ability of Pseudomonas sp. to process these different plastic polymers and their by-products. These factors include cell surface attachment within biofilms, catalytic enzymes involved in oxidation or hydrolysis of the plastic polymer, metabolic pathways responsible for uptake and assimilation of plastic fragments and chemical factors that are advantageous or inhibitory to the biodegradation process. We also highlight future research directions required in order to harness fully the capabilities of Pseudomonas sp. in bioremediation strategies towards eliminating plastic wastes. © 2017 The Society for Applied Microbiology.

  6. Synergism of the combinations of imipenem plus ciprofloxacin and imipenem plus amikacin against Pseudomonas aeruginosa and other bacterial pathogens.

    OpenAIRE

    Bustamante, C I; Drusano, G L; Wharton, R C; Wade, J C

    1987-01-01

    The combinations of imipenem plus ciprofloxacin and imipenem plus amikacin were investigated for their activity against Pseudomonas aeruginosa and other bacterial pathogens. For imipenem-susceptible P. aeruginosa, synergy of imipenem plus ciprofloxacin and imipenem plus amikacin was observed against 36 and 45% of the strains, respectively. The incidence of synergy against imipenem-resistant isolates of P. aeruginosa was 10% for both combinations. Antagonism was not observed with either combin...

  7. Imipenem, meropenem, or doripenem to treat patients with Pseudomonas aeruginosa ventilator-associated pneumonia.

    Science.gov (United States)

    Luyt, Charles-Edouard; Aubry, Alexandra; Lu, Qin; Micaelo, Maïté; Bréchot, Nicolas; Brossier, Florence; Brisson, Hélène; Rouby, Jean-Jacques; Trouillet, Jean-Louis; Combes, Alain; Jarlier, Vincent; Chastre, Jean

    2014-01-01

    Only limited data exist on Pseudomonas aeruginosa ventilator-associated pneumonia (VAP) treated with imipenem, meropenem, or doripenem. Therefore, we conducted a prospective observational study in 169 patients who developed Pseudomonas aeruginosa VAP. Imipenem, meropenem, and doripenem MICs for Pseudomonas aeruginosa isolates were determined using Etests and compared according to the carbapenem received. Among the 169 isolates responsible for the first VAP episode, doripenem MICs were lower (Pimipenem and meropenem (MIC50s, 0.25, 2, and 0.38, respectively); 61%, 64%, and 70% were susceptible to imipenem, meropenem, and doripenem, respectively (P was not statistically significant). Factors independently associated with carbapenem resistance were previous carbapenem use (within 15 days) and mechanical ventilation duration before VAP onset. Fifty-six (33%) patients had at least one VAP recurrence, and 56 (33%) died. Factors independently associated with an unfavorable outcome (recurrence or death) were a high day 7 sequential organ failure assessment score and mechanical ventilation dependency on day 7. Physicians freely prescribed a carbapenem to 88 patients: imipenem for 32, meropenem for 24, and doripenem for 32. The remaining 81 patients were treated with various antibiotics. Imipenem-, meropenem-, and doripenem-treated patients had similar VAP recurrence rates (41%, 25%, and 22%, respectively; P=0.15) and mortality rates (47%, 25%, and 22%, respectively; P=0.07). Carbapenem resistance emerged similarly among patients treated with any carbapenem. No carbapenem was superior to another for preventing carbapenem resistance emergence.

  8. Pseudomonas fluorescens-like bacteria from the stomach: a microbiological and molecular study.

    Science.gov (United States)

    Patel, Saurabh Kumar; Pratap, Chandra Bhan; Verma, Ajay Kumar; Jain, Ashok Kumar; Dixit, Vinod Kumar; Nath, Gopal

    2013-02-21

    To characterize oxidase- and urease-producing bacterial isolates, grown aerobically, that originated from antral biopsies of patients suffering from acid peptic diseases. A total of 258 antral biopsy specimens were subjected to isolation of bacteria followed by tests for oxidase and urease production, acid tolerance and aerobic growth. The selected isolates were further characterized by molecular techniques viz. amplifications for 16S rRNA using universal eubacterial and HSP60 gene specific primers. The amplicons were subjected to restriction analysis and partial sequencing. A phylogenetic tree was generated using unweighted pair group method with arithmetic mean (UPGMA) from evolutionary distance computed with bootstrap test of phylogeny. Assessment of acidity tolerance of bacteria isolated from antrum was performed using hydrochloric acid from 10(-7) mol/L to 10(-1) mol/L. Of the 258 antral biopsy specimens collected from patients, 179 (69.4%) were positive for urease production by rapid urease test and 31% (80/258) yielded typical Helicobacter pylori (H. pylori) after 5-7 d of incubation under a microaerophilic environment. A total of 240 (93%) antral biopsies yielded homogeneous semi-translucent and small colonies after overnight incubation. The partial 16S rRNA sequences revealed that the isolates had 99% similarity with Pseudomonas species. A phylogenetic tree on the basis of 16S rRNA sequences denoted that JQ927226 and JQ927227 were likely to be related to Pseudomonas fluorescens (P. fluorescens). On the basis of HSP60 sequences applied to the UPGMA phylogenetic tree, it was observed that isolated strains in an aerobic environment were likely to be P. fluorescens, and HSP60 sequences had more discriminatory potential rather than 16S rRNA sequences. Interestingly, this bacterium was acid tolerant for hours at low pH. Further, a total of 250 (96.9%) genomic DNA samples of 258 biopsy specimens and DNA from 240 bacterial isolates were positive for the 613 bp

  9. Pseudomonas aeruginosa Infections in a Tertiary Hospital in Nigeria ...

    African Journals Online (AJOL)

    Background: Pseudomonas aeruginosa is a known opportunistic pathogen frequently causing serious infections. It exhibits innate resistance to a wide range of antibiotics thus causing high rates of morbidity and mortality worldwide. Objective: This study was done to determine the distribution and the antibiotic susceptibility ...

  10. Mathematical modelling of temperature effect on growth kinetics of Pseudomonas spp. on sliced mushroom (Agaricus bisporus).

    Science.gov (United States)

    Tarlak, Fatih; Ozdemir, Murat; Melikoglu, Mehmet

    2018-02-02

    The growth data of Pseudomonas spp. on sliced mushrooms (Agaricus bisporus) stored between 4 and 28°C were obtained and fitted to three different primary models, known as the modified Gompertz, logistic and Baranyi models. The goodness of fit of these models was compared by considering the mean squared error (MSE) and the coefficient of determination for nonlinear regression (pseudo-R 2 ). The Baranyi model yielded the lowest MSE and highest pseudo-R 2 values. Therefore, the Baranyi model was selected as the best primary model. Maximum specific growth rate (r max ) and lag phase duration (λ) obtained from the Baranyi model were fitted to secondary models namely, the Ratkowsky and Arrhenius models. High pseudo-R 2 and low MSE values indicated that the Arrhenius model has a high goodness of fit to determine the effect of temperature on r max . Observed number of Pseudomonas spp. on sliced mushrooms from independent experiments was compared with the predicted number of Pseudomonas spp. with the models used by considering the B f and A f values. The B f and A f values were found to be 0.974 and 1.036, respectively. The correlation between the observed and predicted number of Pseudomonas spp. was high. Mushroom spoilage was simulated as a function of temperature with the models used. The models used for Pseudomonas spp. growth can provide a fast and cost-effective alternative to traditional microbiological techniques to determine the effect of storage temperature on product shelf-life. The models can be used to evaluate the growth behaviour of Pseudomonas spp. on sliced mushroom, set limits for the quantitative detection of the microbial spoilage and assess product shelf-life. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Kinetic and thermodynamic studies on the adsorption of heavy metals from aqueous solution by melanin nanopigment obtained from marine source: Pseudomonas stutzeri.

    Science.gov (United States)

    Manirethan, Vishnu; Raval, Keyur; Rajan, Reju; Thaira, Harsha; Balakrishnan, Raj Mohan

    2018-05-15

    The difficulty in removal of heavy metals at concentrations below 10 mg/L has led to the exploration of efficient adsorbents for removal of heavy metals. The adsorption capacity of biosynthesized melanin for Mercury (Hg(II)), Chromium (Cr(VI)), Lead (Pb(II)) and Copper (Cu(II)) was investigated at different operating conditions like pH, time, initial concentration and temperature. The heavy metals adsorption process was well illustrated by the Lagergren's pseudo-second-order kinetic model and the equilibrium data fitted excellently to Langmuir isotherm. Maximum adsorption capacity obtained from Langmuir isotherm for Hg(II) was 82.4 mg/g, Cr(VI) was 126.9 mg/g, Pb(II) was 147.5 mg/g and Cu(II) was 167.8 mg/g. The thermodynamic parameters revealed that the adsorption of heavy metals on melanin is favorable, spontaneous and endothermic in nature. Binding of heavy metals on melanin surface was proved by Fourier Transform Infrared Spectroscopy (FT-IR) and X-ray Photoelectron Spectroscopy (XPS). Contemplating the results, biosynthesized melanin can be a potential adsorbent for efficient removal of Hg(II), Cr(VI), Pb(II) and Cu(II) ions from aqueous solution. Copyright © 2018 Elsevier Ltd. All rights reserved.

  12. The consistent differential expression of genetic pathways following exposure of an industrial Pseudomonas aeruginosa strain to preservatives and a laundry detergent formulation

    Science.gov (United States)

    Amézquita, Alejandro; Le Marc, Yvan; Bull, Matthew J; Connor, Thomas R; Mahenthiralingam, Eshwar

    2018-01-01

    Abstract Pseudomonas aeruginosa is a common contaminant associated with product recalls in the home and personal care industry. Preservation systems are used to prevent spoilage and protect consumers, but greater knowledge is needed of preservative resistance mechanisms used by P. aeruginosa contaminants. We aimed to identify genetic pathways associated with preservative exposure by using an industrial P. aeruginosa strain and implementing RNA-Seq to understand gene expression changes in response to industry relevant conditions. The consistent differential expression of five genetic pathways during exposure to multiple industrial growth conditions associated with benzisothiazolone (BIT) and phenoxyethanol (POE) preservatives, and a laundry detergent (LD) formulation, was observed. A MexPQ-OpmE Resistance Nodulation Division efflux pump system was commonly upregulated in response to POE, a combination of BIT and POE, and LD together with BIT. In response to all industry conditions, a putative sialic acid transporter and isoprenoid biosynthesis gnyRDBHAL operon demonstrated consistent upregulation. Two operons phnBA and pqsEDCBA involved in Pseudomonas quinolone signaling production and quorum-sensing were also consistently downregulated during exposure to all the industry conditions. The ability to identify consistently differentially expressed genetic pathways in P. aeruginosa can inform the development of future targeted preservation systems that maintain product safety and minimise resistance development. PMID:29548026

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

    Energy Technology Data Exchange (ETDEWEB)

    Guilan, Niu [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); Junjie, Zhang [State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071 (China); Shuo, Zhao [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); Hong, Liu [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.

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

    International Nuclear Information System (INIS)

    Niu Guilan; Zhang Junjie; Zhao Shuo; Liu Hong; Boon, Nico; Zhou Ningyi

    2009-01-01

    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

  15. Enhanced extracellular chitinase production in Pseudomonas fluorescens: biotechnological implications

    Directory of Open Access Journals (Sweden)

    Azhar Alhasawi

    2017-06-01

    Full Text Available Chitin is an important renewable biomass of immense commercial interest. The processing of this biopolymer into value-added products in an environmentally-friendly manner necessitates its conversion into N-acetyl glucosamine (NAG, a reaction mediated by the enzyme chitinase. Here we report on the ability of the soil microbe Pseudomonas fluorescens to secrete copious amounts of chitinase in the spent fluid when cultured in mineral medium with chitin as the sole source of carbon and nitrogen. Although chitinase was detected in various cellular fractions, the enzyme was predominantly localized in the extracellular component that was also rich in NAG and glucosamine. Maximal amounts of chitinase with a specific activity of 80 µmol NAG produced mg–1 protein min–1 was obtained at pH 8 after 6 days of growth in medium with 0.5 g of chitin. In-gel activity assays and Western blot studies revealed three isoenzymes. The enzyme had an optimal activity at pH 10 and a temperature range of 22–38 ℃. It was stable for up to 3 months. Although it showed optimal specificity toward chitin, the enzyme did readily degrade shrimp shells. When these shells (0.1 g were treated with the extracellular chitinase preparation, NAG [3 mmoles (0.003 g-mol] was generated in 6 h. The extracellular nature of the enzyme coupled with its physico-chemical properties make this chitinase an excellent candidate for biotechnological applications.

  16. Ferric-Pyoverdine Recognition by Fpv Outer Membrane Proteins of Pseudomonas protegens Pf-5

    Science.gov (United States)

    Hartney, Sierra L.; Mazurier, Sylvie; Girard, Maëva K.; Mehnaz, Samina; Davis, Edward W.; Gross, Harald; Lemanceau, Philippe

    2013-01-01

    The soil bacterium Pseudomonas protegens Pf-5 (previously called P. fluorescens Pf-5) produces two siderophores, enantio-pyochelin and a compound in the large and diverse pyoverdine family. Using high-resolution mass spectroscopy, we determined the structure of the pyoverdine produced by Pf-5. In addition to producing its own siderophores, Pf-5 also utilizes ferric complexes of some pyoverdines produced by other strains of Pseudomonas spp. as sources of iron. Previously, phylogenetic analysis of the 45 TonB-dependent outer membrane proteins in Pf-5 indicated that six are in a well-supported clade with ferric-pyoverdine receptors (Fpvs) from other Pseudomonas spp. We used a combination of phylogenetics, bioinformatics, mutagenesis, pyoverdine structural determinations, and cross-feeding bioassays to assign specific ferric-pyoverdine substrates to each of the six Fpvs of Pf-5. We identified at least one ferric-pyoverdine that was taken up by each of the six Fpvs of Pf-5. Functional redundancy of the Pf-5 Fpvs was also apparent, with some ferric-pyoverdines taken up by all mutants with a single Fpv deletion but not by a mutant having deletions in two of the Fpv-encoding genes. Finally, we demonstrated that phylogenetically related Fpvs take up ferric complexes of structurally related pyoverdines, thereby establishing structure-function relationships that can be employed in the future to predict the pyoverdine substrates of Fpvs in other Pseudomonas spp. PMID:23222724

  17. Vesiculation from Pseudomonas aeruginosa under SOS.

    Science.gov (United States)

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

    2012-01-01

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

  18. Rapid and sensitive detection of Pseudomonas aeruginosa in chlorinated water and aerosols targeting gyrB gene using real-time PCR.

    Science.gov (United States)

    Lee, C S; Wetzel, K; Buckley, T; Wozniak, D; Lee, J

    2011-10-01

    For the rapid detection of Pseudomonas aeruginosa from chlorinated water and aerosols, gyrB gene-based real-time PCR assay was developed and investigated. Two novel primer sets (pa722F/746MGB/899R and pa722F/746MGB/788R) were designed using the most updated 611 Pseudomonas and 748 other bacterial gyrB genes for achieving high specificity. Their specificity showed 100% accuracy when tested with various strains including clinical isolates from cystic fibrosis patients. The assay was tested with Ps. aeruginosa-containing chlorinated water and aerosols to simulate the waterborne and airborne transmission routes (detection limit 3·3 × 10² CFU per PCR-2·3 × 10³ CFU per PCR). No chlorine interference in real-time PCR was observed at drinking water level (c. 1 mg l⁻¹), but high level of chorine (12 mg l⁻¹) interfered the assay, and thus neutralization was needed. Pseudomonas aeruginosa in aerosol was successfully detected after capturing with gelatin filters with minimum 2 min of sampling time when the initial concentration of 10⁴ CFU ml⁻¹ bacteria existed in the nebulizer. A highly specific and rapid assay (2-3 h) was developed by targeting gyrB gene for the detection of Ps. aeruginosa in chlorinated water and aerosols, combined with optimized sample collection methods and sample processing, so the direct DNA extraction from either water or aerosol was possible while achieving the desired sensitivity of the method.   The new assay can provide timely and accurate risk assessment to prevent Ps. aeruginosa exposure from water and aerosol, resulting in reduced disease burden, especially among immune-compromised and susceptible individuals. This approach can be easily utilized as a platform technology for the detection of other types of micro-organisms, especially for those that are transmitted via water and aerosol routes, such as Legionella pneumophila. © 2011 The Authors. Journal of Applied Microbiology © 2011 The Society for Applied Microbiology.

  19. Antibacterial properties of Chinese herbal medicines against nosocomial antibiotic resistant strains of Pseudomonas aeruginosa in Taiwan.

    Science.gov (United States)

    Liu, Ching-Shen; Cham, Thau-Ming; Yang, Cheng-Hong; Chang, Hsueh-Wei; Chen, Chia-Hong; Chuang, Li-Yeh

    2007-01-01

    Pseudomonas aeruginosa is well-recognized as a nosocomial pathogen, which exhibits inherent drug resistance. In this study, the antibacterial activity of ethanol extracts of 58 Chinese herbal medicines used in Taiwan were tested against 89 nosocomial antibiotic resistant strains of Pseudomonas aeruginosa. The results gathered by the disc diffusion method showed that 26 out of the 58 herbal extracts exhibited antibacterial activity. Among the 26 herbal extracts, 10 extracts showed broad-spectrum antibacterial activities and were selected for further antibacterial property assay. The minimum inhibitory concentrations (MIC) of the active partition fractions ranged from 0.25 to 11.0 mg/L. The presence of flavonoid compounds in the active fractions of test herbal extracts was observed by the TLC-bioautography. The results from the time-kill assay revealed that most of the herbal extracts completely killed the test organisms within 4 hours. Exposure of the test strains to a sub-MIC level of the herbal extracts for 10 consecutive subcultures did not induce resistance to the active components. A combination of the active herbal fractions with antibiotics showed that one of the herbal medicines, the hexane fraction of Ramulus Cinnamomi, possessed a synergistic effect with tetracycline, gentamycin, and streptomycin. In conclusion, the tested Chinese medical herbs have the potential to be developed into natural antibiotics. This is the first evaluation for screening large amounts of medical plants against nosocomial antibiotic resistant bacteria in Taiwan.

  20. Disruption of transporters affiliated with enantio-pyochelin biosynthesis gene cluster of Pseudomonas protegens Pf-5 has pleiotropic effects

    Science.gov (United States)

    Pseudomonas protegens Pf-5 (formerly Pseudomonas fluorescens) is a biocontrol bacterium that produces the siderophore enantio-pyochelin under conditions of iron starvation in a process that is often accompanied by the secretion of its biosynthesis intermediates, salicylic acid and dihydroaeruginoic ...