Mitigating Observation Perturbation Sampling Errors in the Stochastic EnKF

KAUST Repository

Hoteit, Ibrahim

2015-03-17

The stochastic ensemble Kalman filter (EnKF) updates its ensemble members with observations perturbed with noise sampled from the distribution of the observational errors. This was shown to introduce noise into the system and may become pronounced when the ensemble size is smaller than the rank of the observational error covariance, which is often the case in real oceanic and atmospheric data assimilation applications. This work introduces an efficient serial scheme to mitigate the impact of observations’ perturbations sampling in the analysis step of the EnKF, which should provide more accurate ensemble estimates of the analysis error covariance matrices. The new scheme is simple to implement within the serial EnKF algorithm, requiring only the approximation of the EnKF sample forecast error covariance matrix by a matrix with one rank less. The new EnKF scheme is implemented and tested with the Lorenz-96 model. Results from numerical experiments are conducted to compare its performance with the EnKF and two standard deterministic EnKFs. This study shows that the new scheme enhances the behavior of the EnKF and may lead to better performance than the deterministic EnKFs even when implemented with relatively small ensembles.

Mitigating Observation Perturbation Sampling Errors in the Stochastic EnKF

KAUST Repository

Hoteit, Ibrahim; Pham, D.-T.; El Gharamti, Mohamad; Luo, X.

2015-01-01

The stochastic ensemble Kalman filter (EnKF) updates its ensemble members with observations perturbed with noise sampled from the distribution of the observational errors. This was shown to introduce noise into the system and may become pronounced when the ensemble size is smaller than the rank of the observational error covariance, which is often the case in real oceanic and atmospheric data assimilation applications. This work introduces an efficient serial scheme to mitigate the impact of observations’ perturbations sampling in the analysis step of the EnKF, which should provide more accurate ensemble estimates of the analysis error covariance matrices. The new scheme is simple to implement within the serial EnKF algorithm, requiring only the approximation of the EnKF sample forecast error covariance matrix by a matrix with one rank less. The new EnKF scheme is implemented and tested with the Lorenz-96 model. Results from numerical experiments are conducted to compare its performance with the EnKF and two standard deterministic EnKFs. This study shows that the new scheme enhances the behavior of the EnKF and may lead to better performance than the deterministic EnKFs even when implemented with relatively small ensembles.

45 CFR 707.7 - Employment.

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2010-10-01

... 45 Public Welfare 3 2010-10-01 2010-10-01 false Employment. 707.7 Section 707.7 Public Welfare... § 707.7 Employment. No qualified individual with disabilities shall, on the basis of disability, be subjected to discrimination in employment under any program or activity conducted by the Agency. The...

45 CFR 707.10 - Auxiliary aids.

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2010-10-01

... 45 Public Welfare 3 2010-10-01 2010-10-01 false Auxiliary aids. 707.10 Section 707.10 Public Welfare Regulations Relating to Public Welfare (Continued) COMMISSION ON CIVIL RIGHTS ENFORCEMENT OF... § 707.10 Auxiliary aids. (a) The Agency shall furnish appropriate auxiliary aids where necessary to...

Occurrence of bla genes encoding carbapenem-resistant Pseudomonas aeruginosa and Acinetobacter baumannii from Intensive Care Unit in a tertiary care hospital.

Science.gov (United States)

Subramaniyan, Jayanthi Siva; Sundaram, Jeya Meenakshi

2018-01-01

ICU shows increasing incidence of infection associated with the use of invasive procedures for the diagnostic purpose as well as the indiscriminate use of antibiotics. Pseudomonas aeruginosa and Acinetobacter species are "very successful" pathogen and the emergence of the Metallo-β-Lactamases (MBL) is becoming a therapeutic challenge. To isolate the Nonfermenting Gram negative bacilli from the ICU samples. To identify the metallo betalactamase producers and to detect the bla gene presence among the Pseudomonas aeruginosa and Acinetobacter baumannii . The Nonfermenting Gram negative bacilli isolates from the ICU samples were taken over for 5 years (2009-2014) in a tertiary care hospital. The isolates of Pseudomonas species and Acinetobacter species were confirmed by API analyser and processed according to standard procedures. Detection of the MBL producers were done by E strip method and subjected for bla gene detection by PCR method. In our study a total of 195 isolates of NFGNB were obtained from various ICU. Of these MBL producers, 26 % were Pseudomonas aeruginosa and 25 % were Acinetobacter baumannii . The subtypes of bla VIM MBL producing P.aeruginosa were 26%. The predominant gene coding for MBL activity in A.baumannii were found to be bla OXA gene 11.9%. The gene accession numbers were KF975367, KF975372. We have to control the development and dissemination of these superbugs among the ICU's.

46 CFR 11.707 - Examination requirements.

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2010-10-01

... 46 Shipping 1 2010-10-01 2010-10-01 false Examination requirements. 11.707 Section 11.707 Shipping... OFFICER ENDORSEMENTS Professional Requirements for Pilots § 11.707 Examination requirements. (a) An... required to pass the examination described in subpart I of this part. (b) An applicant for an extension of...

Mice lacking the kf-1 gene exhibit increased anxiety- but not despair-like behavior

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Atsushi Tsujimura

2008-09-01

Full Text Available KF-1 was originally identified as a protein encoded by human gene with increased expression in the cerebral cortex of a patient with Alzheimer’s disease. In mouse brain, kf-1 mRNA is detected predominantly in the hippocampus and cerebellum, and kf-1 gene expression is elevated also in the frontal cortex of rats after chronic antidepressant treatments. KF-1 mediates E2-dependent ubiquitination and may modulate cellular protein levels as an E3 ubiquitin ligase, though its target proteins are not yet identified. To elucidate the role of kf-1 in the central nervous system, we generated kf-1 knockout mice by gene targeting, using Cre-lox recombination. The resulting kf-1−/− mice were normal and healthy in appearance. Behavioral analyses revealed that kf-1−/− mice showed significantly increased anxiety-like behavior compared with kf-1+/+ littermates in the light/dark transition and elevated plus maze tests; however, no significant differences were observed in exploratory locomotion using the open field test or in behavioral despair using the forced swim and tail suspension tests. These observations suggest that KF-1 suppresses selectively anxiety under physiological conditions probably through modulating protein levels of its unknown target(s. Interestingly, kf-1−/− mice exhibited significantly increased prepulse inhibition, which is usually reduced in human schizophrenic patients. Thus, the kf-1−/− mice provide a novel animal model for elucidating molecular mechanisms of psychiatric diseases such as anxiety/depression, and may be useful for screening novel anxiolytic/antidepressant compounds.

23 CFR 650.707 - Rating factor.

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2010-04-01

... 23 Highways 1 2010-04-01 2010-04-01 false Rating factor. 650.707 Section 650.707 Highways FEDERAL..., STRUCTURES, AND HYDRAULICS Discretionary Bridge Candidate Rating Factor § 650.707 Rating factor. (a) The.... ER15OC02.010 The lower the rating factor, the higher the priority for selection and funding. (b) The terms...

Bioremediation of Petroleum hydrocarbon by using Pseudomonas species isolated from Petroleum contaminated soil

OpenAIRE

Vijay Kumar; Simranjeet Singh; Anu Manhas; Joginder Singh; Sourav Singla; Parvinder Kaur; Shivika Data; Pritika Negi; Arjun Kalia

2014-01-01

A newly isolated strain Pseudomonas fluorescens (Accession number KF 279042.1) have potential in diesel degradation and can be recommended for bioremediation of sites that are contaminated with diesel. This bacterium was characterized on the basis of microbiological, biochemical and molecular analysis. Bacterial growth optimization was studied based on carbon source, nitrogen source, pH and temperature. The strain was selected based on its ability to show growth in medium containing diesel. I...

New KF-PP-SVM classification method for EEG in brain-computer interfaces.

Science.gov (United States)

Yang, Banghua; Han, Zhijun; Zan, Peng; Wang, Qian

2014-01-01

Classification methods are a crucial direction in the current study of brain-computer interfaces (BCIs). To improve the classification accuracy for electroencephalogram (EEG) signals, a novel KF-PP-SVM (kernel fisher, posterior probability, and support vector machine) classification method is developed. Its detailed process entails the use of common spatial patterns to obtain features, based on which the within-class scatter is calculated. Then the scatter is added into the kernel function of a radial basis function to construct a new kernel function. This new kernel is integrated into the SVM to obtain a new classification model. Finally, the output of SVM is calculated based on posterior probability and the final recognition result is obtained. To evaluate the effectiveness of the proposed KF-PP-SVM method, EEG data collected from laboratory are processed with four different classification schemes (KF-PP-SVM, KF-SVM, PP-SVM, and SVM). The results showed that the overall average improvements arising from the use of the KF-PP-SVM scheme as opposed to KF-SVM, PP-SVM and SVM schemes are 2.49%, 5.83 % and 6.49 % respectively.

Nuclear fusion project. Semi-annual report of the Association KfK/EURATOM

International Nuclear Information System (INIS)

1986-11-01

Nuclear fusion is one of the main activities of the Karlsruhe Nuclear Research Center (KfK). It is organized as a project under the Directorate of Reactor Development and Safety. The work of KfK concentrates on technology aspects of nuclear fusion with magnetic confinement. It is part of the European Fusion Programme where KfK participates as an association to EURATOM. Close links have been established to the Max Planck Institute for Plasma Physics (IPP). In the Entwicklungsgemeinschaft Kernfusion KfK and IPP cooperate for the development of future fusion experiments joining the experience gained in plasma physics (IPP) and materials, safety, and nuclear technology (KfK), respectively. As in the present strategy of the European Fusion Programme the Next European Tokamak (NET) is foreseen as the major next step, most of the activities of KfK address this subject. In addition to the contributions to NET, studies are carried out to innovate INTOR, the worldwide cooperation for an experimental reactor under the auspices of IAEA. Furthermore, the Entwicklungsgemeinschaft Kernfusion has evaluated the feasibility of a fusion reactor with a stellarator confinement. (orig./GG)

32 CFR 707.12 - Amphibious operations lights.

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2010-07-01

... 32 National Defense 5 2010-07-01 2010-07-01 false Amphibious operations lights. 707.12 Section 707... WITH RESPECT TO ADDITIONAL STATION AND SIGNAL LIGHTS § 707.12 Amphibious operations lights. Naval vessels engaged in night amphibious operations may display various arrangements of light systems...

23 CFR 710.707 - Fair market value.

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2010-04-01

... 23 Highways 1 2010-04-01 2010-04-01 false Fair market value. 710.707 Section 710.707 Highways... REAL ESTATE Concession Agreements § 710.707 Fair market value. A highway agency shall receive fair market value for any concession agreement involving a federally funded highway. ...

Inhibition of food-related bacteria by antibacterial substances produced by Pseudomonas sp. strains isolated from pasteurized milk

Directory of Open Access Journals (Sweden)

Ana Beatriz Ferreira Rangel

2013-12-01

Full Text Available In this work, the production of antimicrobial substances by strains of Pseudomonas sp. isolated from pasteurized milk and their potential action against food-related bacteria were investigated. Samples of pasteurized milk were purchased from arbitrarily chosen commercial establishments in the city of Rio de Janeiro, Brazil. Of the four samples analyzed, three presented several typical colonies of Pseudomonas. About 100 colonies were chosen and subjected to biochemical tests for confirmation of their identity. Eighteen strains of the Pseudomonas genus were identified and submitted to tests for the production of antimicrobial substances. Twelve strains (66.7% were identified as Pseudomonas fluorescens, four (22.2% as P. aeruginosa, one (5.5% as P. mendocina and one (5.5% as P. pseudoalcaligenes. Only two P. fluorescens strains were unable to produce any antimicrobial substance against any of the indicator strains tested. Most of the strains presented a broad spectrum of action, inhibiting reference and food-related strains such as Proteus vulgaris, Proteus mirabilis, Hafnia alvei, Yersinia enterocolitica, Escherichia coli and Salmonella typhi. Five antimicrobial substance-producing strains, which presented the broadest spectrum of action, were also tested against Staphylococcus aureus reference strains and 26 Staphylococcus sp. strains isolated from foods, some of which were resistant to antibiotics. The producer strains 8.1 and 8.3, both P. aeruginosa, were able to inhibit all the staphylococcal strains tested. The antimicrobial substances produced by strains 8.1 and 8.3 did not seem to be typical bacteriocins, since they were resistant to the three proteolytic enzymes tested. Experiments involving the characterization of these substances are being carried out in order to evaluate their biotechnological application.

7 CFR 707.3 - Death.

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2010-01-01

... 7 Agriculture 7 2010-01-01 2010-01-01 false Death. 707.3 Section 707.3 Agriculture Regulations of the Department of Agriculture (Continued) FARM SERVICE AGENCY, DEPARTMENT OF AGRICULTURE AGRICULTURAL... Death. (a) Where any person who is otherwise eligible to receive a payment dies before the payment is...

12 CFR 707.8 - Advertising.

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2010-01-01

... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Advertising. 707.8 Section 707.8 Banks and... Advertising. (a) Misleading or inaccurate advertisements. An advertisement must not: (1) Be misleading or... balance required to earn the advertised annual percentage yield. For tiered-rate accounts, the minimum...

KfK Nuclear Safety Project. First semiannual report 1985

International Nuclear Information System (INIS)

1985-11-01

The semiannual progress report 1985/1 is a description of work within the Nuclear Safety Project performed in the first six month of 1985 in the nuclear safety field by KfK institutes and departements and by external institutions on behalf of KfK. The chosen kind of this report is that of short summaries, containing the topics: work performed, results obtained and plans for future work. (orig./HP) [de

46 CFR 108.707 - First aid kit.

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2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false First aid kit. 108.707 Section 108.707 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Miscellaneous Equipment § 108.707 First aid kit. Each unit must have a first-aid kit approved by the Mine Safety...

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.

32 CFR 707.2 - Man overboard lights.

Science.gov (United States)

2010-07-01

... 32 National Defense 5 2010-07-01 2010-07-01 false Man overboard lights. 707.2 Section 707.2 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY NAVIGATION SPECIAL RULES WITH RESPECT TO ADDITIONAL STATION AND SIGNAL LIGHTS § 707.2 Man overboard lights. Naval vessels may display, as a means of indicating man overboard, two...

PacCYP707A2 negatively regulates cherry fruit ripening while PacCYP707A1 mediates drought tolerance.

Science.gov (United States)

Li, Qian; Chen, Pei; Dai, Shengjie; Sun, Yufei; Yuan, Bing; Kai, Wenbin; Pei, Yuelin; He, Suihuan; Liang, Bin; Zhang, Yushu; Leng, Ping

2015-07-01

Sweet cherry is a non-climacteric fruit and its ripening is regulated by abscisic acid (ABA) during fruit development. In this study, four cDNAs (PacCYP707A1-4) encoding 8'-hydroxylase, a key enzyme in the oxidative catabolism of ABA, were identified in sweet cherry fruits using tobacco rattle virus-induced gene silencing (VIGS) and particle bombardment approaches. Quantitative real-time PCR confirmed significant down-regulation of target gene transcripts in VIGS-treated cherry fruits. In PacCYP707A2-RNAi-treated fruits, ripening and fruit colouring were promoted relative to control fruits, and both ABA accumulation and PacNCED1 transcript levels were up-regulated by 140%. Silencing of PacCYP707A2 by VIGS significantly altered the transcripts of both ABA-responsive and ripening-related genes, including the ABA metabolism-associated genes NCED and CYP707A, the anthocyanin synthesis genes PacCHS, PacCHI, PacF3H, PacDFR, PacANS, and PacUFGT, the ethylene biosynthesis gene PacACO1, and the transcription factor PacMYBA. The promoter of PacMYBA responded more strongly to PacCYP707A2-RNAi-treated fruits than to PacCYP707A1-RNAi-treated fruits. By contrast, silencing of PacCYP707A1 stimulated a slight increase in fruit colouring and enhanced resistance to dehydration stress compared with control fruits. These results suggest that PacCYP707A2 is a key regulator of ABA catabolism that functions as a negative regulator of fruit ripening, while PacCYP707A1 regulates ABA content in response to dehydration during fruit development. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology.

49 CFR 236.707 - Blade, semaphore.

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2010-10-01

... 49 Transportation 4 2010-10-01 2010-10-01 false Blade, semaphore. 236.707 Section 236.707 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Blade, semaphore. The extended part of a semaphore arm which shows the position of the arm. ...

10 CFR 70.7 - Employee protection.

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2010-01-01

... occurs because the employee has engaged in protected activities. An employee's engagement in protected... 10 Energy 2 2010-01-01 2010-01-01 false Employee protection. 70.7 Section 70.7 Energy NUCLEAR... Employee protection. (a) Discrimination by a Commission licensee, an applicant for a Commission license, or...

24 CFR 3280.707 - Heat producing appliances.

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2010-04-01

... 24 Housing and Urban Development 5 2010-04-01 2010-04-01 false Heat producing appliances. 3280.707... Systems § 3280.707 Heat producing appliances. (a) Heat-producing appliances and vents, roof jacks and... appliance, the heating appliance shall be installed by the manufacturer of the manufactured home in...

20 CFR 410.707 - Hearings and appeals.

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2010-04-01

... 20 Employees' Benefits 2 2010-04-01 2010-04-01 false Hearings and appeals. 410.707 Section 410.707 Employees' Benefits SOCIAL SECURITY ADMINISTRATION FEDERAL COAL MINE HEALTH AND SAFETY ACT OF 1969, TITLE IV-BLACK LUNG BENEFITS (1969- ) Rules for the Review of Denied and Pending Claims Under the Black Lung...

Reduction of Used Memory Ensemble Kalman Filtering (RumEnKF): A data assimilation scheme for memory intensive, high performance computing

Science.gov (United States)

Hut, Rolf; Amisigo, Barnabas A.; Steele-Dunne, Susan; van de Giesen, Nick

2015-12-01

Reduction of Used Memory Ensemble Kalman Filtering (RumEnKF) is introduced as a variant on the Ensemble Kalman Filter (EnKF). RumEnKF differs from EnKF in that it does not store the entire ensemble, but rather only saves the first two moments of the ensemble distribution. In this way, the number of ensemble members that can be calculated is less dependent on available memory, and mainly on available computing power (CPU). RumEnKF is developed to make optimal use of current generation super computer architecture, where the number of available floating point operations (flops) increases more rapidly than the available memory and where inter-node communication can quickly become a bottleneck. RumEnKF reduces the used memory compared to the EnKF when the number of ensemble members is greater than half the number of state variables. In this paper, three simple models are used (auto-regressive, low dimensional Lorenz and high dimensional Lorenz) to show that RumEnKF performs similarly to the EnKF. Furthermore, it is also shown that increasing the ensemble size has a similar impact on the estimation error from the three algorithms.

Electric conductivity of salt melts containing KCL, KF and K2TaF7

International Nuclear Information System (INIS)

Agulyanskij, A.I.; Stangrit, P.T.; Konstantinov, V.I.

1978-01-01

Given are electric conductivity measurement results depending on the temperature and composition of the molten KF-K 2 TaF 7 , KCl-K 2 TaF 7 systems and also melts close in their composition to industrial electrolytes, KCl-KF (in mass ratio of 2:1) with addition of K 2 TaF 7 up to 25 mass%. Presented are electric conductivity molecular isotherms of the KF-K 2 TaF 7 , KCl-K 2 TaF 7 systems at 800 deg C and specific electric conductivity dependence of KCl-KF-K 2 TaF 7 melts on K 2 TaF 7 composition at 800 deg C and 900 deg C. Proceeding from the shape of molecular and specific electric conductivity isotherms a conclusion is made about existence of the following tantalum-containing ions: TaF 7 2- , TaF 6 - and TaF 6 Cl 2- in the investigated melts

45 CFR 95.707 - Equipment management and disposition.

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2010-10-01

... participation in the costs of replacement equipment shall be limited to the additional outlay. (4) If the... 45 Public Welfare 1 2010-10-01 2010-10-01 false Equipment management and disposition. 95.707... PROGRAMS) Equipment Acquired Under Public Assistance Programs § 95.707 Equipment management and disposition...

45 CFR 707.6 - General prohibitions against discrimination.

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2010-10-01

... 45 Public Welfare 3 2010-10-01 2010-10-01 false General prohibitions against discrimination. 707.6.... COMMISSION ON CIVIL RIGHTS § 707.6 General prohibitions against discrimination. (a) No qualified individual... benefits of, or otherwise be subjected to discrimination under any program or activity conducted by the...

34 CFR 76.707 - When obligations are made.

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2010-07-01

... 34 Education 1 2010-07-01 2010-07-01 false When obligations are made. 76.707 Section 76.707 Education Office of the Secretary, Department of Education STATE-ADMINISTERED PROGRAMS What Are the... subgrantee receives the services. (f) Travel When the travel is taken. (g) Rental of real or personal...

34 CFR 75.707 - When obligations are made.

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2010-07-01

... 34 Education 1 2010-07-01 2010-07-01 false When obligations are made. 75.707 Section 75.707 Education Office of the Secretary, Department of Education DIRECT GRANT PROGRAMS What Are the Administrative... services. (f) Travel When the travel is taken. (g) Rental of real or personal property When the grantee...

Velocity of sound in, and adiabatic compressibility of, Molten LiF-NaF, LiF-KF, NaF-KF mixtures

International Nuclear Information System (INIS)

Minchenko, V.I.; Konovalov, Y.V.; Smirnov, M.V.

1986-01-01

The authors measured the velocity of sound as a function of temperature at 1.5 zHM frequency in LiF-NaF, NaF-KF, LiF-KF melts over the entire range of their compositions. The measurements were made by comparison of the phases of a reference pulse signal and a signal reflected from the bottom of the crucible. The specified temperatures were maintained constant within plus or minus 1 degree. The sound conductor consisted of a cylindrical rod of sintered beryllium oxide, which does not interact with test melts. The study shows that the velocity of sound decreases linearly with increase of the temperature. The values of the constants of the empirical equations are presented in a table, with indication of the temperature range. The dependence of the velocity of sound on composition of the melts is shown, where isotherms for 1250 K are given as an example. Variation of the composition by 1-2 mole % leads to increase or decrease of the velocity of sound by 5-10 m

48 CFR 46.707 - Pricing aspects of fixed-price incentive contract warranties.

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2010-10-01

... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Pricing aspects of fixed-price incentive contract warranties. 46.707 Section 46.707 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION CONTRACT MANAGEMENT QUALITY ASSURANCE Warranties 46.707 Pricing aspects of...

Influence of KF substitution on the ferroelectric phase transition of lead titanate single crystals studied by Brillouin light scattering

Directory of Open Access Journals (Sweden)

Seonhyeop Shin

2015-06-01

Full Text Available The elastic properties of KF-substituted perovskite lead titanate (PbTiO3 were investigated by dielectric measurements and Brillouin light scattering. The ferroelectric phase transition occurred at substantially lower temperature due to KF substitution, which was attributed to the modification of the covalency in Pb–O and Ti–O bonds. The longitudinal acoustic (LA mode of KF-substituted PbTiO3 showed a frequency softening in the paraelectric phase, which was accompanied by increasing acoustic damping. This indicated that polarization fluctuations responsible for the acoustic anomalies were enhanced by KF substitution.

Density of salt melts containing KF, KCl, K2TaF7 and Ta2O5

International Nuclear Information System (INIS)

Agulyanskij, A.I.; Stangrit, P.T.; Konstantinov, V.I.

1978-01-01

The results of density measurements by hydrostatic weighing are given for molten K 2 TaF 7 - KF, K 2 TaF 7 -KCL, K 2 TaF 7 - KF - KCl and K 2 TaF 7 - KF - KCl - Ta 2 O 5 mixtures depending on their temperature and composition. The density of the last two systems was measured at compositions close to those of commercial electrolytes. The obtained specific volume - composition dependencies show that no interaction is taking place in the mixtures studied. It is, therefore, believed that, in the K 2 TaF 7 - KF melt, tantalum is mainly present as a complex TaF 7 2- ion, and, in the K 2 TaF 7 - KCl mlt, a certain amount of TaF 6 - ions may be formed along with TaF 7 2-

47 CFR 64.707 - Public dissemination of information by providers of operator services.

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2010-10-01

... 47 Telecommunication 3 2010-10-01 2010-10-01 false Public dissemination of information by providers of operator services. 64.707 Section 64.707 Telecommunication FEDERAL COMMUNICATIONS COMMISSION... § 64.707 Public dissemination of information by providers of operator services. Providers of operator...

Ensemble singular vectors and their use as additive inflation in EnKF

Directory of Open Access Journals (Sweden)

Shu-Chih Yang

2015-07-01

Full Text Available Given an ensemble of forecasts, it is possible to determine the leading ensemble singular vector (ESV, that is, the linear combination of the forecasts that, given the choice of the perturbation norm and forecast interval, will maximise the growth of the perturbations. Because the ESV indicates the directions of the fastest growing forecast errors, we explore the potential of applying the leading ESVs in ensemble Kalman filter (EnKF for correcting fast-growing errors. The ESVs are derived based on a quasi-geostrophic multi-level channel model, and data assimilation experiments are carried out under framework of the local ensemble transform Kalman filter. We confirm that even during the early spin-up starting with random initial conditions, the final ESVs of the first analysis with a 12-h window are strongly related to the background errors. Since initial ensemble singular vectors (IESVs grow much faster than Lyapunov Vectors (LVs, and the final ensemble singular vectors (FESVs are close to convergence to leading LVs, perturbations based on leading IESVs grow faster than those based on FESVs, and are therefore preferable as additive inflation. The IESVs are applied in the EnKF framework for constructing flow-dependent additive perturbations to inflate the analysis ensemble. Compared with using random perturbations as additive inflation, a positive impact from using ESVs is found especially in areas with large growing errors. When an EnKF is ‘cold-started’ from random perturbations and poor initial condition, results indicate that using the ESVs as additive inflation has the advantage of correcting large errors so that the spin-up of the EnKF can be accelerated.

Electric conductivity of low-temperature molten electrolyte KF-AlF3 with additions of LiF and Al2O3

International Nuclear Information System (INIS)

Apisarov, A.P.; Kryukovskij, V.A.; Zajkov, Yu.P.; Red'kin, A.A.; Tkacheva, O.Yu.; Khokhlov, V.A.

2007-01-01

Electric conductivity of LiF, Al 2 O 3 doped KF-AlF 3 (Cryolite Ratio CR=1.3) molten electrolytes was estimated on the basis of empiric equations. Specific electric conductivity of KF-AlF 3 , KF-AIF 3 -AI 2 O 3 , KF-AlF 3 -LiF, KF-AlF 3 -LiF-Al 2 0 3 molten mixtures was measured in the range 687-797 Deg C. Cells with the pyrolytic boron nitride capillary and parallel molybdena electrodes were applied for the determination of electric conductivity. Comparison of calculated and experimental data of the specific electric conductivity of cryolite-alumina melts confirms that the offered model of the calculation adequate represents temperature and concentration dependencies, and it permits forecasting its change under the introduction of different additives in electrolyte [ru

Efficient KF loaded on MgCaAl hydrotalcite-like compounds in the transesterification of Jatropha curcas oil

International Nuclear Information System (INIS)

Guzmán-Vargas, Ariel; Santos-Gutiérrez, Teresa; Lima, Enrique; Flores-Moreno, Jorge L.; Oliver-Tolentino, Miguel A.; Martínez-Ortiz, María de J.

2015-01-01

Highlights: • MgCaAl hydrotalcite-like compounds were synthetized. • After KF impregnation and calcination fluorinated species were detected. • Fluorinated species were stables and actives. • LDH composition and KF load effect were evaluated in biodiesel production. - Abstract: In this work a series of MgCaAl hydrotalcite-like compounds were synthetized by coprecipitation method at constant pH. In order to obtain the catalysts, the samples were modified with KF by incipient wetness impregnation at different wt%, after that, they were dried and calcined to obtain the mixed oxides. The effect of divalent cations ratio and KF load were studied in the transesterification reaction of Jatropha curcas oil to obtain biodiesel employing an inedible oil. XRD analysis showed typical diffraction patterns of LDH, by nitrogen physisorption the LDH mesoporous structure was also confirmed, 27 Al NMR spectra showed bands at 10 and 88 ppm attributed to the Al coordination before and after thermal treatment. While for the impregnated samples after calcination the profiles exhibited the mixed oxide formation, in addition, another peaks appeared associated to the formation of various fluorinated species as shown by XRD, additionally, 19 F NMR showed a main signal at −180 ppm indicating the presence of active tetrahedral aluminum fluoride species. The reaction evolution was monitoring calculating the oil conversion to biodiesel by integration of the signal spectra using 1 H NMR spectroscopy. The results of catalytic tests in transesterification reaction showed a direct correlation between Mg/Ca ratio and KF content in the oil conversion to biodiesel, the higher conversion was achieved (90%) when Mg/Ca = 1 and KF load was 30 wt%

Efficient KF loaded on MgCaAl hydrotalcite-like compounds in the transesterification of Jatropha curcas oil

Energy Technology Data Exchange (ETDEWEB)

Guzmán-Vargas, Ariel, E-mail: aguzmanv@ipn.mx [ESIQIE-IPN, Departamento de Ingeniería Química, Laboratorio de Investigación en Materiales Porosos, Catálisis Ambiental y Química Fina, UPALM Edif.7 P.B. Zacatenco, México D.F. 07738 (Mexico); Santos-Gutiérrez, Teresa [ESIQIE-IPN, Departamento de Ingeniería Química, Laboratorio de Investigación en Materiales Porosos, Catálisis Ambiental y Química Fina, UPALM Edif.7 P.B. Zacatenco, México D.F. 07738 (Mexico); Lima, Enrique [IIM-Universidad Nacional Autónoma de México, Circuito exterior s/n, Cd. Universitaria, 04510 México DF (Mexico); Flores-Moreno, Jorge L. [UAM-Azcapotzalco, Área de Química de Materiales, Av. San Pablo 180, Col. Reynosa Tamaulipas, 02200 México DF (Mexico); Oliver-Tolentino, Miguel A.; Martínez-Ortiz, María de J. [ESIQIE-IPN, Departamento de Ingeniería Química, Laboratorio de Investigación en Materiales Porosos, Catálisis Ambiental y Química Fina, UPALM Edif.7 P.B. Zacatenco, México D.F. 07738 (Mexico)

2015-09-15

Highlights: • MgCaAl hydrotalcite-like compounds were synthetized. • After KF impregnation and calcination fluorinated species were detected. • Fluorinated species were stables and actives. • LDH composition and KF load effect were evaluated in biodiesel production. - Abstract: In this work a series of MgCaAl hydrotalcite-like compounds were synthetized by coprecipitation method at constant pH. In order to obtain the catalysts, the samples were modified with KF by incipient wetness impregnation at different wt%, after that, they were dried and calcined to obtain the mixed oxides. The effect of divalent cations ratio and KF load were studied in the transesterification reaction of Jatropha curcas oil to obtain biodiesel employing an inedible oil. XRD analysis showed typical diffraction patterns of LDH, by nitrogen physisorption the LDH mesoporous structure was also confirmed, {sup 27}Al NMR spectra showed bands at 10 and 88 ppm attributed to the Al coordination before and after thermal treatment. While for the impregnated samples after calcination the profiles exhibited the mixed oxide formation, in addition, another peaks appeared associated to the formation of various fluorinated species as shown by XRD, additionally, {sup 19}F NMR showed a main signal at −180 ppm indicating the presence of active tetrahedral aluminum fluoride species. The reaction evolution was monitoring calculating the oil conversion to biodiesel by integration of the signal spectra using {sup 1}H NMR spectroscopy. The results of catalytic tests in transesterification reaction showed a direct correlation between Mg/Ca ratio and KF content in the oil conversion to biodiesel, the higher conversion was achieved (90%) when Mg/Ca = 1 and KF load was 30 wt%.

10 CFR 707.4 - Definitions.

Science.gov (United States)

2010-01-01

... ENERGY WORKPLACE SUBSTANCE ABUSE PROGRAMS AT DOE SITES General Provisions § 707.4 Definitions. For the...-controlled operation, if the deviation has environmental, public health and safety, or national security... supervisors or managers, or by a bargaining unit representative. Rehabilitation means a formal treatment...

Facile preparation of highly pure KF-ZrF4 molten salt

Science.gov (United States)

Zong, Guoqiang; Cui, Zhen-Hua; Zhang, Zhi-Bing; Zhang, Long; Xiao, Ji-Chang

2018-03-01

The preparation of highly pure KF-ZrF4 (FKZr) molten salt, a potential secondary coolant in molten salt reactors, was realized simply by heating a mixture of (NH4)2ZrF6 and KF. X-ray diffraction analysis indicated that the FKZr molten salt was mainly composed of KZrF5 and K2ZrF6. The melting point of the prepared FKZr molten salt was 420-422 °C under these conditions. The contents of all metal impurities were lower than 20 ppm, and the content of oxygen was lower than 400 ppm. This one-step protocol avoids the need for a tedious procedure to prepare ZrF4 and for an additional purification process to remove oxide impurities, and is therefore a convenient, efficient and economic preparation method for high-purity FKZr molten salt.

10 CFR 707.2 - Scope.

Science.gov (United States)

2010-01-01

...) High risk of danger to life, the environment, public health and safety, or national security; or (iii... authority of the Atomic Energy Act of 1954, as amended: (1) Management and operating contracts; and (2... WORKPLACE SUBSTANCE ABUSE PROGRAMS AT DOE SITES General Provisions § 707.2 Scope. (a) This part applies to...

29 CFR 780.707 - Establishments “commonly recognized” as country elevators.

Science.gov (United States)

2010-07-01

... 29 Labor 3 2010-07-01 2010-07-01 false Establishments âcommonly recognizedâ as country elevators. 780.707 Section 780.707 Labor Regulations Relating to Labor (Continued) WAGE AND HOUR DIVISION, DEPARTMENT OF LABOR STATEMENTS OF GENERAL POLICY OR INTERPRETATION NOT DIRECTLY RELATED TO REGULATIONS EXEMPTIONS APPLICABLE TO AGRICULTURE, PROCESSING O...

Draft Genome Sequence of Cupriavidus pauculus Strain KF709, a Biphenyl-Utilizing Bacterium Isolated from Biphenyl-Contaminated Soil

OpenAIRE

Watanabe, Takahito; Yamazoe, Atsushi; Hosoyama, Akira; Fujihara, Hidehiko; Suenaga, Hikaru; Hirose, Jun; Futagami, Taiki; Goto, Masatoshi; Kimura, Nobutada; Furukawa, Kensuke

2015-01-01

We report the draft genome sequence of Cupriavidus pauculus strain KF709, which comprises 6,826,799 bp with 6,272 coding sequences. The strain KF709 utilizes biphenyl and degrades low-chlorinated biphenyls; however, it possesses fewer coding sequences involved in the degradation of aromatic compounds than other strains belonging to the Betaproteobacteria.

The Solubility of Aluminum in Cryolite-Based Electrolyte-Containing KF

Science.gov (United States)

Zhang, Yu; Yu, Jiangyu; Gao, Bingliang; Liu, Yibai; Hu, Xianwei; Shi, Zhongning; Wang, Zhaowen

2016-04-01

The solubility of aluminum in NaF-AlF3-CaF2-KF-A12O3 electrolyte system at 1253 K (980 °C) has been measured by the analysis of quenched samples saturated with aluminum. The content of the dissolved metal in the quenched melt was determined by collecting the volume of hydrogen gas when a finely crushed sample is treated with HCl. Addition of 0 to 5 pct KF has no obvious effect on the solubility of aluminum in cryolite-based melts with molar ratio of NaF/AlF3 (cryolite ratio) ranging from 2.2 to 3.0. The solubility of aluminum increases from 0.015 to 0.026 wt pct with cryolite ratio increases from 2.2 to 4.0 in the NaF-AlF3-5 wt pct CaF2-3 wt pct A12O3 electrolyte at 1253 K (980 °C). Aluminum solubility was affected by both chemical replacement reaction of Al + 3NaF = AlF3 + 3Na and physical dissolution.

Joint Parametric Fault Diagnosis and State Estimation Using KF-ML Method

DEFF Research Database (Denmark)

Sun, Zhen; Yang, Zhenyu

2014-01-01

The paper proposes a new method for a kind of parametric fault online diagnosis with state estimation jointly. The considered fault affects not only the deterministic part of the system but also the random circumstance. The proposed method first applies Kalman Filter (KF) and Maximum Likelihood (...

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...

Draft Genome Sequence of Cupriavidus pauculus Strain KF709, a Biphenyl-Utilizing Bacterium Isolated from Biphenyl-Contaminated Soil.

Science.gov (United States)

Watanabe, Takahito; Yamazoe, Atsushi; Hosoyama, Akira; Fujihara, Hidehiko; Suenaga, Hikaru; Hirose, Jun; Futagami, Taiki; Goto, Masatoshi; Kimura, Nobutada; Furukawa, Kensuke

2015-03-26

We report the draft genome sequence of Cupriavidus pauculus strain KF709, which comprises 6,826,799 bp with 6,272 coding sequences. The strain KF709 utilizes biphenyl and degrades low-chlorinated biphenyls; however, it possesses fewer coding sequences involved in the degradation of aromatic compounds than other strains belonging to the Betaproteobacteria. Copyright © 2015 Watanabe et al.

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?

User manual for the KfK code PCROSS

International Nuclear Information System (INIS)

Ravndal, S.; Oblozinsky, P.; Kelzenberg, S.; Cierjacks, S.

1991-08-01

The PCROSS code calculates the so-called 'pseudo' cross sections for sequential (x,n) reactions and merges them together with 'collapsed' cross sections for neutron induced reactions into one file of cross sections. The file is tailored to provide an input for the FISPACT inventory code that calculates the activation and related radiological quantities of material irradiated in a neutron flux. The present report describes the structure of the KfK code PCROSS, outlines the role of subroutines, and provides necessary information for a practical user of the code. (orig.) [de

Electrochemical behavior of boron in LiF-NaF-KF- melts

DEFF Research Database (Denmark)

Polyakova, L.P.; Bukatova, G.A.; Polyakova, E.G.

1996-01-01

The electrochemical reduction of B(III) to B(0) in KBF4-LiF-NaF-KF melts has been studied by voltammetric and chronopotentiometric methods, Glassy carbon, Pt, and Ag were used as working electrode materials. Only in the case of Ag was the reduction not complicated by interaction between boron...

12 CFR 707.1 - Authority, purpose, coverage and effect on State laws.

Science.gov (United States)

2010-01-01

... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Authority, purpose, coverage and effect on... AFFECTING CREDIT UNIONS TRUTH IN SAVINGS § 707.1 Authority, purpose, coverage and effect on State laws. (a... National Credit Union Administration. In addition, the advertising rules in § 707.8 apply to any person who...

5 CFR 330.707 - Reporting vacancies to OPM.

Science.gov (United States)

2010-01-01

... RECRUITMENT, SELECTION, AND PLACEMENT (GENERAL) Interagency Career Transition Assistance Plan for Displaced Employees § 330.707 Reporting vacancies to OPM. (a) Agencies are required to report all competitive service...

An adaptive hybrid EnKF-OI scheme for efficient state-parameter estimation of reactive contaminant transport models

KAUST Repository

El Gharamti, Mohamad; Valstar, Johan R.; Hoteit, Ibrahim

2014-01-01

Reactive contaminant transport models are used by hydrologists to simulate and study the migration and fate of industrial waste in subsurface aquifers. Accurate transport modeling of such waste requires clear understanding of the system's parameters, such as sorption and biodegradation. In this study, we present an efficient sequential data assimilation scheme that computes accurate estimates of aquifer contamination and spatially variable sorption coefficients. This assimilation scheme is based on a hybrid formulation of the ensemble Kalman filter (EnKF) and optimal interpolation (OI) in which solute concentration measurements are assimilated via a recursive dual estimation of sorption coefficients and contaminant state variables. This hybrid EnKF-OI scheme is used to mitigate background covariance limitations due to ensemble under-sampling and neglected model errors. Numerical experiments are conducted with a two-dimensional synthetic aquifer in which cobalt-60, a radioactive contaminant, is leached in a saturated heterogeneous clayey sandstone zone. Assimilation experiments are investigated under different settings and sources of model and observational errors. Simulation results demonstrate that the proposed hybrid EnKF-OI scheme successfully recovers both the contaminant and the sorption rate and reduces their uncertainties. Sensitivity analyses also suggest that the adaptive hybrid scheme remains effective with small ensembles, allowing to reduce the ensemble size by up to 80% with respect to the standard EnKF scheme. © 2014 Elsevier Ltd.

Synthesis of biodiesel using potassium fluoride (KF) supported by hydrotalcite and process optimization by Box-Behnken design

Energy Technology Data Exchange (ETDEWEB)

Singh, Bhaskar; Sharma, Yogesh C. [Banaras Hindu University, Department of Applied Chemistry, Institute of Technology, Varanasi (India); Birla, Ashish; Upadhyay, S.N. [Banaras Hindu University, Department of Chemical Engineering and Technology, Institute of Technology, Varanasi (India); Yaakob, Zahira [Universiti Kebangsaan Malaysia, Department of Chemical and Process Engineering, Selangor (Malaysia)

2012-12-15

Biodiesel has been developed using a heterogeneous catalyst potassium fluoride (KF) supported on hydrotalcite (HT) and waste frying oil (WFO) as feedstock. Hydrotalcite was synthesized by co-precipitation method using mixture of Mg(NO{sub 3}){sub 2}.6H{sub 2}O and Al(NO{sub 3}){sub 2}.9H{sub 2}O slowly added to a solution containing NaOH and Na{sub 2}CO{sub 3} and calcined at 500 C. KF was impregnated on hydrotalcite at KF/HT load ratio of 80:100 by addition of a small amount of water. Biodiesel was developed using KF/HT as heterogeneous catalyst by transesterification. Box-Behnken Design using Minitab 15.1 Statistical Software and Design-Expert (Demo version 8.0.6.1) software were used as statistical tool for design of experiments and optimization of fatty acid methyl ester yield. A high yield and conversion of biodiesel was obtained by optimization of variables affecting the reaction. The variables affected the reaction in the priority order of: catalyst amount >> molar ratio (methanol to oil) > reaction time. A 12:1 methanol to WFO molar ratio, 2.5 wt.% of catalyst at 60 C in 1 h reaction time gave a high fatty acid methyl ester yield of >98 %. The quantitative analysis of the product (i.e., biodiesel) was done on a Fourier-transform-nuclear magnetic resonance spectrometer. (orig.)

An adaptive hybrid EnKF-OI scheme for efficient state-parameter estimation of reactive contaminant transport models

KAUST Repository

El Gharamti, Mohamad

2014-09-01

Reactive contaminant transport models are used by hydrologists to simulate and study the migration and fate of industrial waste in subsurface aquifers. Accurate transport modeling of such waste requires clear understanding of the system\\'s parameters, such as sorption and biodegradation. In this study, we present an efficient sequential data assimilation scheme that computes accurate estimates of aquifer contamination and spatially variable sorption coefficients. This assimilation scheme is based on a hybrid formulation of the ensemble Kalman filter (EnKF) and optimal interpolation (OI) in which solute concentration measurements are assimilated via a recursive dual estimation of sorption coefficients and contaminant state variables. This hybrid EnKF-OI scheme is used to mitigate background covariance limitations due to ensemble under-sampling and neglected model errors. Numerical experiments are conducted with a two-dimensional synthetic aquifer in which cobalt-60, a radioactive contaminant, is leached in a saturated heterogeneous clayey sandstone zone. Assimilation experiments are investigated under different settings and sources of model and observational errors. Simulation results demonstrate that the proposed hybrid EnKF-OI scheme successfully recovers both the contaminant and the sorption rate and reduces their uncertainties. Sensitivity analyses also suggest that the adaptive hybrid scheme remains effective with small ensembles, allowing to reduce the ensemble size by up to 80% with respect to the standard EnKF scheme. © 2014 Elsevier Ltd.

10 CFR 707.8 - Applicant drug testing.

Science.gov (United States)

2010-01-01

... DEPARTMENT OF ENERGY WORKPLACE SUBSTANCE ABUSE PROGRAMS AT DOE SITES Procedures § 707.8 Applicant drug... final selection for employment or assignment to such a position. Provisions of this part do not prohibit contractors from conducting drug testing on applicants for employment in any position. ...

Metabolic characterization and transformation of the non-dairy Lactococcus lactis strain KF147, for production of ethanol from xylose

DEFF Research Database (Denmark)

Petersen, Kia Vest; Liu, Jianming; Chen, Jun

2017-01-01

producing ethanol as the sole fermentation product with a high yield corresponding to 83% of the theoretical maximum. The results clearly indicate the great potential of using the more metabolically diverse non-dairy L. lactis strains for bio-production based on xylose containing feedstocks.......The non-dairy lactic acid bacterium Lactococcus lactis KF147 can utilize xylose as the sole energy source. To assess whether KF147 could serve as a platform organism for converting second generation sugars into useful chemicals, we characterized growth and product formation for KF147 when grown...... the arcA gene encoding the arginine deiminase. The fermentation product profile suggested two routes for xylose degradation, the phosphoketolase pathway and the pentose phosphate pathway. Inactivation of the phosphoketolase pathway redirected the entire flux through the pentose phosphate pathway whereas...

Production of a Biofuel that Keeps the Glycerol as a Monoglyceride by Using Supported KF as Heterogeneous Catalyst

Directory of Open Access Journals (Sweden)

Juan Calero

2014-06-01

Full Text Available This study describes the results obtained in the synthesis of a biofuel that avoids the production of glycerol by applying supported KF as alkaline heterogeneous catalyst, to generate two moles of fatty acid methyl esters and one mole of monoglyceride from one mol of triglyceride. In this respect, the selective transesterification process of sunflower oil with methanol was carried out with KF (10 wt% supported on three different solids, Al2O3, ZnO and MgO. The standard experimental conditions employed in the heterogeneous selective methanolysis reaction were: 12 mL of sunflower oil, 2.7 mL of methanol, 0.8 g of catalyst, at 65 °C temperature and one hour of reaction time. In all cases 100% conversion was obtained, with high selectivity values, greater than 90%, and quite suitable viscosity values, 4.5–8.5 cSt. In this way, the best catalytic behavior in the first use was obtained by using Al2O3 as support. However, although in the five consecutive reuses all catalysts exhibited a continuous decrease in their catalytic activities; the lower one was for KF catalyst using MgO as support. In summary, these three KF supported catalysts are very suitable to obtain a new biofuel, similar to conventional biodiesel, applicable to diesel engines.

Electric conductivity of molten mixtures of ternary mutual KF-KCl-ZrF4 system

International Nuclear Information System (INIS)

Darienko, S.E.; Raspopin, S.P.; Chervinskij, Yu.F.

1988-01-01

Using the relative capillary method at the frequency of 50 kHz the specific electric conductivity of molten mixtures of the KF-KCl-ZnF 4 system is measured. All the measurements were made in the atmosphere of purified argon. Temperature dependence of electric conductivity of the mixtures studied (800-1260 K) is described by the equations of exponential type with sufficient accuracy. Curves of identical specific electric conductivity of the three-component system are presented. With an increase in zirconium tetrachloride concentration in the mixtures electric conductivity of the melts decreases. On the basis of the measurement results of KF-ZrF 4 and KCl-ZrF 4 molten mixture specific electric conductivity and data on the melt density the values of molar electric conductivity at 1200 K are calculated

Report on research and development work 1985 on the nuclear fusion project. Annual report of the Association KfK-Euratom

International Nuclear Information System (INIS)

Finken, D.

1986-05-01

The Nuclear Research Centre Karlsruhe and the Max Planck Institute for Plasma Physics together form the Nuclear Fusion Development Association. The partners collaborate with the aim of creating the physical and technical preconditions for the use of the energy released by nuclear fusion and to plan and carry out future large-scale experiments. The work of the Nuclear Research Centre Karlsruhe on fusion with magnetic containment is included in the nuclear fusion project and is part of the European fusion technology programme. The work is supported by an association contract between KfK and Euratom by the European Commission. Connections are built up between areas of work and new projects are prepared by supplementary KfK contributions, mostly studies. This is done with regard to the expansion of the technology programme to be expected for future years and the planning activities for NET. The reports collected here are contributions of the KfK institutes in 1985. The appendix contains a list of the tasks which KfK has taken over from the fusion technology programme of the EEC. References to the institutes' contributions make the assignment of textual contributions easier. (orig.) [de

Nuclear fusion project. Semi-annual report of the Association KfK/EURATOM

International Nuclear Information System (INIS)

Kast, G.

1988-07-01

Short communications give a survey of 38 technology tasks, the development of ECRH power sources at 150 GHz, and 9 NET study are listed in the appendices I and II, respectively, while the KfK departments contributing to the Fusion Project and the Fusion Project Management Staff are listed in appendices III and IV, respectively. (GG)

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.

Nuclear fusion project. Semi-annual report of the Association KfK/EURATOM

International Nuclear Information System (INIS)

Kast, G.

1987-05-01

This semi-annual report gives 36 short descriptions of the work done in the framework of the Nuclear Fusion Project and outlines studies for NET/INTOR and for ECRH power sources at 150 GHz. Tables of fusion technology contracts, of NET contracts, of KfK departments contributing to the Fusion Project, and of the Fusion Project management staff complete this report. (GG)

Isolation and characterization of bacteria from wasted ionic exchange resins kept at Area de Gestion Ezeiza belonging to RA-3 Reactor

International Nuclear Information System (INIS)

Mosquera Rodriguez, Leon; Pizarro, Ramon A.

2009-01-01

A spent ionic exchange resin kept at Area de Gannet's Ezeiza (Age), belonging to RA-3 Reactor, was treated with sterile water. Microorganisms suspended in the aqueous sample were isolated by several methods, broadening as much as possible cell recovery conditions. Bacteria were subject to purity controls and re-isolation when necessary. Characterization of the strains found in the sample included morphological, physiological and biochemical tests as well as stains. Being the spent resins volume reduction at Age the main purpose, a screening experiment is proposed based on bacteria capability to take carbon from the sediment present in the liquid sample. Recovered bacteria are at least the following: Method I: Bacillus cereus, Bacillus circulans, Bacillus sp., Pseudomonas pseudoalcaligenes, Pseudomonas acidovorans, Pseudomonas sp. Method II: Bacillus cereus, Pseudomonas alcaligenes, Flavimonas sp., Agrobacterium sp. Method III: Bacillus circulans, Bacillus sphaericus, Kocuria rosea, Kytococcus sedentarius, Pseudomonas acidovorans. Microorganisms present in the sample are characteristic of those having low microbiological-contamination levels. Way III is an isolation method whose design would lead to find bacteria having the desired properties in order to diminish the volume of RA-3 Reactor spent resins. (author)

Nuclear Fusion Project. Semi-annual report of the Association KfK/EURATOM

International Nuclear Information System (INIS)

Kast, G.

1987-12-01

Short communications give a survey of 38 technology tasks, the development of ECRH power sources at 150 GHz, and 8 NET study contracts. The fusion technology contracts and the NET contracts are listed in the appendices I and II, respectively, while the KfK departments contributing to the Fusion Project and the Fusion Project Management Staff are listed in appendices III and IV, respectively. (GG)

Interfacial phenomena in the reactions of Al-B, Al-Ti-B, and Al-Zr-B alloys with KF-AlF3 and NaF-AlF3 melts

International Nuclear Information System (INIS)

Lee, M.S.; Terry, B.S.; Grieveson, P.

1993-01-01

The interfacial phenomena occurring during the contacting of liquid Al-B, Al-Ti-B, and Al-Zr-B melts with KF-AlF 3 liquid fluxes have been investigated by optical examination of quenched metal drops previously immersed in the liquid fluxes. Reactions in the Al-B/KF-AlF 3 system involve the formation of metastable AlB 12 at the metal/flux interface. At high KBF 4 levels in the flux, the AlB 12 is dispersed in the flux and also at low KBF 4 levels in the metal. Reactions in the Al-Ti-B/KF-AlF 3 system involve the formation of TiB 2 , which may be dispersed in either the metal or the flux depending upon the composition of the flux. The results obtained for the Al-Ti-B/NaF-AlF 3 and Al-Zr-B/KF-AlF 3 systems were similar to those observed for the Al-Ti-B/KF-AlF 3 system

Production of D-malate by maleate hydratase from Pseudomonas pseudoalcaligenes

NARCIS (Netherlands)

Werf, van der M.J.

1994-01-01

The biological activity of a chiral compound with respect to its pharmaceutical and agrochemical activity, flavour and taste can vary dramatically for the different enantiomers. Especially when using chiral compounds for pharmaceutical or agrochemical applications, the presence of the

KfK-seminar series on supercomputing und visualization from May till September 1992

International Nuclear Information System (INIS)

Hohenhinnebusch, W.

1993-05-01

During the period of may 1992 to september 1992 a series of seminars was held at KfK on several topics of supercomputing in different fields of application. The aim was to demonstrate the importance of supercomputing and visualization in numerical simulations of complex physical and technical phenomena. This report contains the collection of all submitted seminar papers. (orig./HP) [de

13 CFR 134.707 - When does the D/GC transmit the protest file and to whom?

Science.gov (United States)

2010-01-01

... Appeals From Women-Owned Small Business Concern (WOSB) and Economically Disadvantaged WOSB Concern (EDWOSB... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false When does the D/GC transmit the protest file and to whom? 134.707 Section 134.707 Business Credit and Assistance SMALL BUSINESS...

Extended software for the KfK K-edge densitometer

International Nuclear Information System (INIS)

Eberle, H.

1985-04-01

In order to further exploit the possibilities of the KfK K-edge densitometer, and to enlarge the range of its application, we have extended and modified the instrument's software. With the new software packages the instrument can now be used for analysis of the actinide elemments Th, U, Np, Pu and Am in single element solutions, and for the simultaneous assay of U and Pu in mixed U/Pu solutions. Provisions have been made for later extensions, allowing the analysis of additional elements combinations, if necessary. The report gives a short description of the new programs, and of the modifications to the previous programs. The listings and the corresponding programs are given in the Appendix. (orig./HP)

­Genomic data mining of the marine actinobacteria Streptomyces sp. H-KF8 unveils insights into multi-stress related genes and metabolic pathways involved in antimicrobial synthesis

Directory of Open Access Journals (Sweden)

Agustina Undabarrena

2017-02-01

Full Text Available Streptomyces sp. H-KF8 is an actinobacterial strain isolated from marine sediments of a Chilean Patagonian fjord. Morphological characterization together with antibacterial activity was assessed in various culture media, revealing a carbon-source dependent activity mainly against Gram-positive bacteria (S. aureus and L. monocytogenes. Genome mining of this antibacterial-producing bacterium revealed the presence of 26 biosynthetic gene clusters (BGCs for secondary metabolites, where among them, 81% have low similarities with known BGCs. In addition, a genomic search in Streptomyces sp. H-KF8 unveiled the presence of a wide variety of genetic determinants related to heavy metal resistance (49 genes, oxidative stress (69 genes and antibiotic resistance (97 genes. This study revealed that the marine-derived Streptomyces sp. H-KF8 bacterium has the capability to tolerate a diverse set of heavy metals such as copper, cobalt, mercury, chromate and nickel; as well as the highly toxic tellurite, a feature first time described for Streptomyces. In addition, Streptomyces sp. H-KF8 possesses a major resistance towards oxidative stress, in comparison to the soil reference strain Streptomyces violaceoruber A3(2. Moreover, Streptomyces sp. H-KF8 showed resistance to 88% of the antibiotics tested, indicating overall, a strong response to several abiotic stressors. The combination of these biological traits confirms the metabolic versatility of Streptomyces sp. H-KF8, a genetically well-prepared microorganism with the ability to confront the dynamics of the fjord-unique marine environment.

Predictability over the North Atlantic ocean in hindcast ensembles of MPI-ESM initialized by EnKF and three nudging systems

Science.gov (United States)

Brune, Sebastian; Pohlmann, Holger; Düsterhus, Andre; Kröger, Jürgen; Müller, Wolfgang; Baehr, Johanna

2016-04-01

We investigate hindcast skill for surface air temperature and upper ocean heat content (0-700m) in the North Atlantic for yearly mean values from 1960 to 2014 in four prediction systems based on the global coupled Max Planck Institute for Meteorology Earth System Model (MPI-ESM). We find that in the North Atlantic and within the four prediction systems under consideration only the EnKF initialized hindcasts reproduce the variability of the reference data well both in terms of anomaly correlation and representation of the probability density function. The systems under consideration only differ in the method how they incorporate surface and sub-surface oceanic temperatures and salinities during assimilation: ensemble Kalman Filter (EnKF), anomaly nudging of ORA reanalysis (BS-1), full field nudging of ORA and GECCO reanalysis, respectively (PT-ORA, PT-GEC). We assess the hindcast skill of each prediction system with reference to HadCRUT4 near surface air temperature data (Morice et al. 2012) and NOAA OC5 upper ocean heat content data (Levitus et al. 2012) using anomaly correlation (ACC) and by analysing the interquartile range (IQR) of the probability density function (PDF). Firstly, we calculate hindcast skill in terms of ACC and IQR against reference data over the whole time period. Here, the hindcast skills of EnKF and BS-1 are better for both ACC and IQR in lead years 2 to 5 when compared to PT-ORA and PT-GEC, their hindcast skill drops off after lead year 1. Secondly, the PDF of the reference data is not uniformly distributed over time. We therefore calculate ACC and IQR for a 20 year moving window. We find hindcast skill in terms of ACC for EnKF and BS-1 in the 1960s and from the 1990s onwards, up to eight lead years in advance, with almost no skill for the time period inbetween. In contrast, there is no skill for PT-ORA and PT-GEC in any period after lead year one. The IQR of reference data is best captured by the EnKF, in the 1960s and 1990s up to lead year

Adenosine A{sub 2A} receptor imaging with [{sup 11}C]KF18446 PET in the rat brain after quinolinic acid lesion. Comparison with the dopamine receptor imaging

Energy Technology Data Exchange (ETDEWEB)

Ishiwata, Kiichi; Ogi, Nobuo; Hayakawa, Nobutaka [Tokyo Metropolitan Inst. of Gerontology, Tokyo (Japan). Positron Medical Center] [and others

2002-11-01

We proposed [{sup 11}C]KF18446 as a selective radioligand for mapping the adenosine A{sub 2A} receptors being highly enriched in the striatum by positron emission tomography (PET). In the present study, we investigated whether [{sup 11}C]KF18446 PET can detect the change in the striatal adenosine A{sub 2A} receptors in the rat after unilateral injection of an excitotoxin quinolinic acid into the striatum, a Huntington's disease model, to demonstrate the usefulness of [{sup 11}C]KF18446. The extent of the striatal lesion was identified based on MRI, to which the PET was co-registered. The binding potential of [{sup 11}C]KF18446 significantly decreased in the quinolinic acid-lesioned striatum. The decrease was comparable to the decrease in the potential of [{sup 11}C] raclopride binding to dopamine D{sub 2} receptors in the lesioned striatum, but seemed to be larger than the decrease in the potential of [{sup 11}C]SCH23390 binding to dopamine D{sub 1} receptors. Ex vivo and in vitro autoradiography validated the PET signals. We concluded that [{sup 11}C]KF18446 PET can detect change in the adenosine A{sub 2A} receptors in the rat model, and will provide a new diagnostic tool for characterizing post-synaptic striatopallidal neurons in the stratum. (author)

20 CFR 404.707 - Original records or copies as evidence.

Science.gov (United States)

2010-04-01

... 20 Employees' Benefits 2 2010-04-01 2010-04-01 false Original records or copies as evidence. 404... DISABILITY INSURANCE (1950- ) Evidence General § 404.707 Original records or copies as evidence. (a) General... original document or record. These original records or documents will be returned to you after we have...

Separating DDTs in edible animal fats using matrix solid-phase dispersion extraction with activated carbon filter, Toyobo-KF.

Science.gov (United States)

Furusawa, Naoto

2006-09-01

A technique is presented for the economical, routine, and quantitative analysis of contamination by dichloro-diphenyl-trichloroethanes (DDTs) [pp'-DDT, pp'-dichlorodiphenyl dichloroethylene, and pp'-dichlorodiphenyl dichloreothane in beef tallow and chicken fat samples, based on their separation using matrix solid-phase dispersion (MSPD) extraction with Toyobo-KF, an activated carbon fiber. Toyobo-KF is a newly applied MSPD sorbent, and it is followed by reversed-phase high-performance liquid chromatography (HPLC) with a photodiode array detector. The resulting analytical performance parameters [recoveries of spiked DDTs (0.1, 0.2, and 0.4 microg/g) > or = 81%, with relative standard deviations of < or = 8% (n = 5), and quantitation limits < or = 0.03 microg/g], with minimal handling and cost-efficiency, indicate that the present MSPD-HPLC method may be a useful tool for routine monitoring of DDT contamination in meat.

KF/Al2O3 as a Recyclable Basic Catalyst for 1,3-Dipolar Cycloaddition Reaction: Synthesis of Indolizine-1-Carbonitrile Derivatives

Directory of Open Access Journals (Sweden)

Abaszadeh Mehdi

2017-07-01

Full Text Available KF/Al2O3 as a green and efficient catalyst has been used for synthesis of indolizine-1-carbonitrile derivatives. It can be proceeded by using 1,3-dipolar cycloaddition reaction of 1-alkyl-2-chloropyridinium bromides, malononitrile and benzaldehyde in ethanol, at reflux. The great advantage of this catalyst is the ease of handling. KF/Al2O3 can be used and removed by filtration, avoiding cumbersome aqueous workups and decreasing solvent waste handling issues. High conversions, short reaction times and a cleaner reaction profiles are some of the outstanding advantages of this method.

Estimation of water level and steam temperature using ensemble Kalman filter square root (EnKF-SR)

Science.gov (United States)

Herlambang, T.; Mufarrikoh, Z.; Karya, D. F.; Rahmalia, D.

2018-04-01

The equipment unit which has the most vital role in the steam-powered electric power plant is boiler. Steam drum boiler is a tank functioning to separate fluida into has phase and liquid phase. The existence in boiler system has a vital role. The controlled variables in the steam drum boiler are water level and the steam temperature. If the water level is higher than the determined level, then the gas phase resulted will contain steam endangering the following process and making the resulted steam going to turbine get less, and the by causing damages to pipes in the boiler. On the contrary, if less than the height of determined water level, the resulted height will result in dry steam likely to endanger steam drum. Thus an error was observed between the determined. This paper studied the implementation of the Ensemble Kalman Filter Square Root (EnKF-SR) method in nonlinear model of the steam drum boiler equation. The computation to estimate the height of water level and the temperature of steam was by simulation using Matlab software. Thus an error was observed between the determined water level and the steam temperature, and that of estimated water level and steam temperature. The result of simulation by Ensemble Kalman Filter Square Root (EnKF-SR) on the nonlinear model of steam drum boiler showed that the error was less than 2%. The implementation of EnKF-SR on the steam drum boiler r model comprises of three simulations, each of which generates 200, 300 and 400 ensembles. The best simulation exhibited the error between the real condition and the estimated result, by generating 400 ensemble. The simulation in water level in order of 0.00002145 m, whereas in the steam temperature was some 0.00002121 kelvin.

KfK analysis of the SUPER-PHENIX-1 control rod experiments. Pt. 1

International Nuclear Information System (INIS)

Giese, H.

1991-03-01

As proposed by the SPX-1 analysis task force, MSM (modified source multiplication) correction factors have been produced for a series of control rod configurations established in the first critical core C1D with minimum fissile loading and in the fully loaded core CMP. The report gives a complete description of the method used at KfK to produce these correction factors and summarises the evaluated experimental results obtained. The KfK method is characterized by a 'two-step-adjustment': A basic reactivity scale adjustment and a subsequent rod worth adjustment. The first adjustment was achieved by 'tuning' either the axialbuckling in the leakage term D B 2 or the average number of neutrons per fission in the production term so that the excess reactivity of the so-called 'Follower-core' with all control rods fully raised was properly reproduced. As this excess reactivity could not be directly determined by an experiment, it had to be assessed from the shut-down worth of the main control system in combination with measured fractions of the S-curve of this system. In the second adjustment, the absorber cross sections were tuned to reproduce experimental rod worths. While for the analysis of the C1D experiments, MSM correction factor calculations were performed in 2D centre-plane geometry only, the analysis of the CMP measurements employed both 2D and 3D calculations. (orig./HP)

Maxwell–Stefan diffusion and dynamical correlation in molten LiF-KF: A molecular dynamics study

Energy Technology Data Exchange (ETDEWEB)

Jain, Richa Naja, E-mail: ltprichanaja@gmail.com; Chakraborty, Brahmananda; Ramaniah, Lavanya M. [High Pressure & Synchrotron Radiation Physics Division, Bhabha Atomic Research Centre, Trombay, Mumbai-85 (India)

2016-05-23

In this work our main objective is to compute Dynamical correlations, Onsager coefficients and Maxwell-Stefan (MS) diffusivities for molten salt LiF-KF mixture at various thermodynamic states through Green–Kubo formalism for the first time. The equilibrium molecular dynamics (MD) simulations were performed using BHM potential for LiF–KF mixture. The velocity autocorrelations functions involving Li ions reflect the endurance of cage dynamics or backscattering with temperature. The magnitude of Onsager coefficients for all pairs increases with increase in temperature. Interestingly most of the Onsager coefficients has almost maximum magnitude at the eutectic composition indicating the most dynamic character of the eutectic mixture. MS diffusivity hence diffusion for all ion pairs increases in the system with increasing temperature. Smooth variation of the diffusivity values denies any network formation in the mixture. Also, the striking feature is the noticeable concentration dependence of MS diffusivity between cation-cation pair, Đ{sub Li-K} which remains negative for most of the concentration range but changes sign to become positive for higher LiF concentration. The negative MS diffusivity is acceptable as it satisfies the non-negative entropy constraint governed by 2{sup nd} law of thermodynamics. This high diffusivity also vouches the candidature of molten salt as a coolant.

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....

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).

Grundwassermodellbildung – Hydrostratigraphische Bewertungen mittels GCI-PetroKf, Datenbank- und Geoinformationssystemen

DEFF Research Database (Denmark)

Koch, Alexander; Fuchs, Sven; Göbel, Patricia

reimportiert und für die Verwendung in Geoinformationssystemen (i.e. ArcGIS) weiter aufbereitet. Über Interpolationsverfahren konnte innerhalb des Programmes ArcGIS ein lateraler Bezug zwischen den verschiedenen Mächtigkeiten hergestellt werden, um so auf weitere Inhomogenitäten im Aufbau des Grundwasserleiter......-Systems schließen zu können. Anschließend wurden mittels ArcGIS die Quartärbasis des Modellraums konstruiert, sowie Grundwasserisolinien- und Grundwasserdifferenzenkarten berechnet. Die Grundwasserdifferenzenkarten reproduzieren gut die Grundwasserabsenkungen im Bereich von lokalen Tagebauen. Insgesamt zeigen sich...... gute Übereinstimmungen mit früheren hydrogeologischen Untersuchungen im Projektgebiet. Die Kombination des PetroKf-Algorithmus mit der Aufbereitung in einer Datenbank, sowie der Weiterverarbeitung in ArcGIS, zeigt einen praktikablen Weg zur Entwicklung und Parametrisierung eines hydrogeologischen...

Plutonium isotopic assay of reprocessing product solutions in the KfK K-edge densitometer

International Nuclear Information System (INIS)

Eberle, H.; Ottmar, H.; Matussek, P.

1985-04-01

The KfK K-edge densiometer, designed for accurate element concentration measurements using the technique of X-ray absorptiometry at the K absorption edge, provides as an additional option the possibility to determine the isotopic composition of freshly separated plutonium from an gamma-spectrometric analysis of its self-radiation. This report describes the underlying methodology and experimental procedures for the isotopic analysis in the K-edge densitometer. The paper also presents and discusses the experimental results so far obtained from routine measurements on reprocessing product solutions. (orig.)

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].

Electrochemical investigation on the redox chemistry of niobium in LiCl-KCl-KF-Na2O melts

DEFF Research Database (Denmark)

Gillesberg, Bo; Bjerrum, Niels; Barner, Jens H. Von

1997-01-01

The system LiCl-KCl-KF-1 mole percent K2NbF7 (molar ration F-/Nb = 8) has been investigated in-the temperature range 370 to 725 degrees C by cyclic and square wave voltammetry. In the temperature range from 370 to 520 degrees C Nb(V) was reduced to Nb(III) in two reversible steps: Nb(V) --> Nb(IV...

Operating software for plutonium measurements in the KfK K-edge densitometer. A user's guide

International Nuclear Information System (INIS)

Eberle, H.

1983-09-01

A set of computer programs has been developed for the execution of plutonium concentration measurements in the KfK K-edge photon absorptiometer for performance evaluation. The programs are implemented on a ND-6620 data acquisition and processing system. A short description of the programs and commands for data accumulation and analysis is given. Nevertheless, the user should be familiar with the ND-6620 data acquisition and processing system, its system software, and with the FORTRAN programming language. (orig./HP)

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.

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.

Status report. KfK contribution to the development of DEMO-relevant test blankets for NET/ITER. Pt. 2: BOT helium cooled solid breeder blanket. Vol. 1

International Nuclear Information System (INIS)

Dalle Donne, M.; Boccaccini, L.V.; Bojarsky, E.; Deckers, H.; Dienst, W.; Doerr, L.; Fischer, U.; Giese, H.; Guenther, E.; Haefner, H.E.; Hofmann, P.; Kappler, F.; Knitter, R.; Kuechle, M.; Moellendorf, U. von; Norajitra, P.; Penzhorn, R.D.; Reimann, G.; Reiser, H.; Schulz, B.; Schumacher, G.; Schwenk-Ferrero, A.; Sordon, G.; Tsukiyama, T.; Wedemeyer, H.; Weimar, P.; Werle, H.; Wiegner, E.; Zimmermann, H.

1991-10-01

The BOT (Breeder Outside Tube) Helium Cooled Breeder Blanket for a fusion Demo reactor and the status of the R and D program is presented. This is the KfK contribution to the European Program for the Demo relevant test plankets to be irradiated in NET/ITER. Volume 1 (KfK 4928) contains the summary, volume 2 (KfK 4929) a more detailed version of the report. In both volumes are described the reasons for the selected design, the reference blanket design for the Demo reactor, the design of test blanket including the ancillary systems together with the present status of the relative R and D program in the fields of neutronic and thermohydraulic calculations, of the electromagnetic forces caused by disruptions, of the development and irradiation of the ceramic breeder material, of the tritium release and recovery, and of the technological investigations. An outlook is given on the required R and D program for the BOT Helium Cooled Solid Breeder Blanket prior to tests in NET/ITER and the proposed test program in NET/ITER. (orig.) [de

Status report. KfK contribution to the development of DEMO-relevant test blankets for NET/ITER. Pt. 2: BOT helium cooled solid breeder blanket. Vol. 2

International Nuclear Information System (INIS)

Dalle Donne, M.; Boccaccini, L.V.; Bojarsky, E.; Deckers, H.; Dienst, W.; Doerr, L.; Fischer, U.; Giese, H.; Guenther, E.; Haefner, H.E.; Hofmann, P.; Kappler, F.; Knitter, R.; Kuechle, M.; Moellendorf, U. von; Norajitra, P.; Penzhorn, R.D.; Reimann, G.; Reiser, H.; Schulz, B.; Schumacher, G.; Schwenk-Ferrero, A.; Sordon, G.; Tsukiyama, T.; Wedemeyer, H.; Weimar, P.; Werle, H.; Wiegner, E.; Zimmermann, H.

1991-10-01

The BOT (Breeder Outside Tube) Helium Cooled Solid Breeder Blanket for a fusion Demo reactor and the status of the R and D program is presented. This is the KfK contribution to the European Program for the Demo relevant test blankets to be irradiated in NET/ITER. Volume 1 (KfK 4928) contains the summary, volume 2 (KfK 4929) a more detailed version of the report. In both volumes are described the reasons for the selected design, the reference blanket design for the Demo reactor, the design of the test blanket including the ancillary systems together with the present status of the relative R and D program in the fields of neutronic and thermohydraulic calculations, of the electromagnetic forces caused by disruptions, of the development and irradiation of the ceramic breeder material, of the tritium release and recovery, and of the technological investigations. An outlook is given on the required R and D program for the BOT Helium Cooled Solid Breeder Blanket prior to tests in NET/ITER and the proposed test program in NET/ITER. (orig.) [de

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...

47 CFR 74.707 - Low power TV and TV translator station protection.

Science.gov (United States)

2010-10-01

... 47 Telecommunication 4 2010-10-01 2010-10-01 false Low power TV and TV translator station... SERVICES Low Power TV, TV Translator, and TV Booster Stations § 74.707 Low power TV and TV translator station protection. (a)(1) A low power TV or TV translator will be protected from interference from other...

Catalytic effect of KF-846 on the reforming of the primary intermediates from the co-pyrolysis of pubescens and LDPE

International Nuclear Information System (INIS)

Liu, Wen-wu; Hu, Chang-wei; Tong, Dong-mei; Yang, Yu; Li, Gui-ying; Zhu, Liang-fang; Tang, Jin-Qiang

2014-01-01

Highlights: • Reforming reactions were inhibited by H 2 , decrease of acidity and low temperature. • There was a synergistic effect on producing hydrogen between Ni and Mo. • The lattice oxygen over catalyst employed might transfer into the intermediates. • Co-pyrolysis, low temperature and N 2 could restrain oxygen transfer to some extent. - Abstract: Co-pyrolysis is regarded as an effective approach to upgrade the quality of pyrolysis products. In this work the activity of KF-846 was evaluated by co-pyrolysis of pubescens and low density polyethylene under different experimental conditions including catalytic mode, pyrolytic atmosphere and temperature, etc. The results showed that the fresh KF-846 exerted strong effects of cyclization, aromatization, hydrogen transfer and vapor-catalytic reforming reactions on the primary intermediates from the co-pyrolysis. The hydrogen-rich gases indicated a synergistic effect between Ni and Mo over KF-846 on producing hydrogen. More importantly, the reforming reactions might be inhibited to some extent by H 2 atmosphere, the low temperature and the decrease of acidity over catalyst. Furthermore, it was deduced that the oxygen over the lattice of catalyst or some intermediates might transfer into other intermediates, possibly resulting in more products with high oxygen content, but it was presumed that the low temperature, co-pyrolysis process and N 2 atmosphere could repress the trend to a certain degree. The mass and energy balance of co-pyrolysis were analyzed, and the main reaction pathways were also proposed. The interference in pyrolysis by regulating the catalytic mode, pyrolytic atmosphere and temperature, acidity over catalyst might posses a certain guiding significance for the pyrolytic technology and the design/selection of catalysts employed

"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 ...

Evaluation of safety assessment methodologies in Rocky Flats Risk Assessment Guide (1985) and Building 707 Final Safety Analysis Report (1987)

International Nuclear Information System (INIS)

Walsh, B.; Fisher, C.; Zigler, G.; Clark, R.A.

1990-01-01

FSARs. Rockwell International, as operating contractor at the Rocky Flats plant, conducted a safety analysis program during the 1980s. That effort resulted in Final Safety Analysis Reports (FSARs) for several buildings, one of them being the Building 707 Final Safety Analysis Report, June 87 (707FSAR) and a Plant Safety Analysis Report. Rocky Flats Risk Assessment Guide, March 1985 (RFRAG85) documents the methodologies that were used for those FSARs. Resources available for preparation of those Rocky Flats FSARs were very limited. After addressing the more pressing safety issues, some of which are described below, the present contractor (EG ampersand G) intends to conduct a program of upgrading the FSARs. This report presents the results of a review of the methodologies described in RFRAG85 and 707FSAR and contains suggestions that might be incorporated into the methodology for the FSAR upgrade effort

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

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.

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...

14 CFR 91.707 - Flights between Mexico or Canada and the United States.

Science.gov (United States)

2010-01-01

... Canada and the United States without filing an IFR or VFR flight plan, as appropriate. ... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Flights between Mexico or Canada and the... Rules Governing Persons on Board Such Aircraft § 91.707 Flights between Mexico or Canada and the United...

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.

ESTUDO DA ESTABILIDADE TÉRMICA DE FIBRA QUERATINA (KF DE PENAS DE FRANGO PARA OBTENÇÃO DE CARBONO (CF

Directory of Open Access Journals (Sweden)

Débora Damasceno Belarmino

2012-07-01

Full Text Available A fibra de queratina de penas de frango foi submetida à análise térmica (TG em sua forma natural e carbonizada, aumentando assim a expansão do reaproveitamento de materiais desperdiçados no Brasil. A partir das curvas obtidas por TG/DTG da pena natural (KF e tratadas (KFNaOH, SCFC e SCFD buscou-se um melhor ciclo de carbonização (pirólise para esse tipo de precursor. O trabalho também trata como um dos focos, o estudo comparativo do comportamento térmico desses materiais. Uma parte da KF foi tratada com hidróxido de sódio (NaOH, e observou-se pelo o resultado TG/DTG que a resistência térmica do material não foi influenciada. Outra parte de KF foi semicarbonizada (220°C sem controle do ambiente térmico e taxas de aquecimento e resfriamento, apresentando colorações diferentes, mais clara (SCFC e mais escura (SCFD. Foi constatado nas curvas de TG/DTG, que esse tratamento de carbonização não é ideal para a obtenção de carbono. Também foi verificado nas curvas de TG/DTG que na CF houve um aumento da estabilidade térmica comparada a todas as outras amostras. Essa pesquisa é uma inovação no que diz respeito à preparação e avaliação de fibras de penas de frango na obtenção de fibras sintetizadas, que atualmente são, em larga escala, derivados do petróleo, lembrando-se da diminuição das reservas de petróleo e da poluição que os mesmos geram ao meio ambiente.

The impact of covariance localization on the performance of an ocean EnKF system assimilating glider data in the Ligurian Sea

Science.gov (United States)

Falchetti, Silvia; Alvarez, Alberto

2018-04-01

Data assimilation through an ensemble Kalman filter (EnKF) is not exempt from deficiencies, including the generation of long-range unphysical correlations that degrade its performance. The covariance localization technique has been proposed and used in previous research to mitigate this effect. However, an evaluation of its performance is usually hindered by the sparseness and unsustained collection of independent observations. This article assesses the performance of an ocean prediction system composed of a multivariate EnKF coupled with a regional configuration of the Regional Ocean Model System (ROMS) with a covariance localization solution and data assimilation from an ocean glider that operated over a limited region of the Ligurian Sea. Simultaneous with the operation of the forecast system, a high-quality data set was repeatedly collected with a CTD sensor, i.e., every day during the period from 5 to 20 August 2013 (approximately 4 to 5 times the synoptic time scale of the area), located on board the NR/V Alliance for model validation. Comparisons between the validation data set and the forecasts provide evidence that the performance of the prediction system with covariance localization is superior to that observed using only EnKF assimilation without localization or using a free run ensemble. Furthermore, it is shown that covariance localization also increases the robustness of the model to the location of the assimilated data. Our analysis reveals that improvements are detected with regard to not only preventing the occurrence of spurious correlations but also preserving the spatial coherence in the updated covariance matrix. Covariance localization has been shown to be relevant in operational frameworks where short-term forecasts (on the order of days) are required.

Resistance to pyridine-based inhibitor KF116 reveals an unexpected role of integrase in HIV-1 Gag-Pol polyprotein proteolytic processing.

Science.gov (United States)

Hoyte, Ashley C; Jamin, Augusta V; Koneru, Pratibha C; Kobe, Matthew J; Larue, Ross C; Fuchs, James R; Engelman, Alan N; Kvaratskhelia, Mamuka

2017-12-01

The pyridine-based multimerization selective HIV-1 integrase (IN) inhibitors (MINIs) are a distinct subclass of allosteric IN inhibitors. MINIs potently inhibit HIV-1 replication during virion maturation by inducing hyper- or aberrant IN multimerization but are largely ineffective during the early steps of viral replication. Here, we investigated the mechanism for the evolution of a triple IN substitution (T124N/V165I/T174I) that emerges in cell culture with a representative MINI, KF116. We show that HIV-1 NL4-3(IN T124N/V165I/T174I) confers marked (>2000-fold) resistance to KF116. Two IN substitutions (T124N/T174I) directly weaken inhibitor binding at the dimer interface of the catalytic core domain but at the same time markedly impair HIV-1 replication capacity. Unexpectedly, T124N/T174I IN substitutions inhibited proteolytic processing of HIV-1 polyproteins Gag and Gag-Pol, resulting in immature virions. Strikingly, the addition of the third IN substitution (V165I) restored polyprotein processing, virus particle maturation, and significant levels of replication capacity. These results reveal an unanticipated role of IN for polyprotein proteolytic processing during virion morphogenesis. The complex evolutionary pathway for the emergence of resistant viruses, which includes the need for the compensatory V165I IN substitution, highlights a relatively high genetic barrier exerted by MINI KF116. Additionally, we have solved the X-ray structure of the drug-resistant catalytic core domain protein, which provides means for rational development of second-generation MINIs. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

On the efficiency of the hybrid and the exact second-order sampling formulations of the EnKF: a reality-inspired 3-D test case for estimating biodegradation rates of chlorinated hydrocarbons at the port of Rotterdam

KAUST Repository

El Gharamti, Mohamad

2016-11-15

This study considers the assimilation problem of subsurface contaminants at the port of Rotterdam in the Netherlands. It involves the estimation of solute concentrations and biodegradation rates of four different chlorinated solvents. We focus on assessing the efficiency of an adaptive hybrid ensemble Kalman filter and optimal interpolation (EnKF-OI) and the exact second-order sampling formulation (EnKFESOS) for mitigating the undersampling of the estimation and observation errors covariances, respectively. A multi-dimensional and multi-species reactive transport model is coupled to simulate the migration of contaminants within a Pleistocene aquifer layer located around 25 m below mean sea level. The biodegradation chain of chlorinated hydrocarbons starting from tetrachloroethene and ending with vinyl chloride is modeled under anaerobic environmental conditions for 5 decades. Yearly pseudo-concentration data are used to condition the forecast concentration and degradation rates in the presence of model and observational errors. Assimilation results demonstrate the robustness of the hybrid EnKF-OI, for accurately calibrating the uncertain biodegradation rates. When implemented serially, the adaptive hybrid EnKF-OI scheme efficiently adjusts the weights of the involved covariances for each individual measurement. The EnKFESOS is shown to maintain the parameter ensemble spread much better leading to more robust estimates of the states and parameters. On average, a well tuned hybrid EnKF-OI and the EnKFESOS respectively suggest around 48 and 21 % improved concentration estimates, as well as around 70 and 23 % improved anaerobic degradation rates, over the standard EnKF. Incorporating large uncertainties in the flow model degrades the accuracy of the estimates of all schemes. Given that the performance of the hybrid EnKF-OI depends on the quality of the background statistics, satisfactory results were obtained only when the uncertainty imposed on the background

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.

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...

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

Pseudomonas sp. BUP6 produces a thermotolerant alkaline lipase with trans-esterification efficiency in producing biodiesel.

Science.gov (United States)

Priji, Prakasan; Sajith, Sreedharan; Faisal, Panichikkal Abdul; Benjamin, Sailas

2017-12-01

The present study describes the characteristics of a thermotolerant and alkaline lipase secreted by Pseudomonas sp. BUP6, a novel rumen bacterium isolated from Malabari goat, and its trans -esterification efficiency in producing biodiesel from used cooking oil (UCO). The extracellular lipase was purified to homogeneity (35.8 times purified with 14.8% yield) employing (NH 4 ) 2 SO 4 salt precipitation and Sephadex G-100 chromatography. The apparent molecular weight of this lipase on SDS-PAGE was 35 kDa, the identity of which was further confirmed by MALDI-TOF/MS. The purified lipase was found stable at a pH range of 7-9 with the maximum activity (707 U/ml) at pH 8.2; and was active at the temperature ranging from 35 to 50 °C with the optimum at 45 °C (891 U/ml). Triton X-100 and EDTA had no effect on the activity of lipase; whereas SDS, Tween-80 and β-mercaptoethanol inhibited its activity significantly. Moreover, Ca 2+ (1.0 mM) enhanced the activity of lipase (1428 U/ml) by 206% vis-à-vis initial activity; while Zn 2+ , Fe 2+ and Cu 2+ decreased the activity significantly. Using para -nitrophenyl palmitate as substrate, the K m (11.6 mM) and V max [668.9 μmol/(min/mg)] of the purified lipase were also determined. Crude lipase was used for analyzing its trans -esterification efficiency with used cooking oil and methanol which resulted in the worthy yield of fatty acid methyl esters, FAME (45%) at 37 °C, indicating its prospects in biodiesel industry. Thus, the lipase secreted by the rumen bacterium, Pseudomonas sp. BUP6, offers great potentials to be used in various industries including the production of biodiesel by trans -esterification.

A Prototype Regional GSI-based EnKF-Variational Hybrid Data Assimilation System for the Rapid Refresh Forecasting System: Dual-Resolution Implementation and Testing Results

Science.gov (United States)

Pan, Yujie; Xue, Ming; Zhu, Kefeng; Wang, Mingjun

2018-05-01

A dual-resolution (DR) version of a regional ensemble Kalman filter (EnKF)-3D ensemble variational (3DEnVar) coupled hybrid data assimilation system is implemented as a prototype for the operational Rapid Refresh forecasting system. The DR 3DEnVar system combines a high-resolution (HR) deterministic background forecast with lower-resolution (LR) EnKF ensemble perturbations used for flow-dependent background error covariance to produce a HR analysis. The computational cost is substantially reduced by running the ensemble forecasts and EnKF analyses at LR. The DR 3DEnVar system is tested with 3-h cycles over a 9-day period using a 40/˜13-km grid spacing combination. The HR forecasts from the DR hybrid analyses are compared with forecasts launched from HR Gridpoint Statistical Interpolation (GSI) 3D variational (3DVar) analyses, and single LR hybrid analyses interpolated to the HR grid. With the DR 3DEnVar system, a 90% weight for the ensemble covariance yields the lowest forecast errors and the DR hybrid system clearly outperforms the HR GSI 3DVar. Humidity and wind forecasts are also better than those launched from interpolated LR hybrid analyses, but the temperature forecasts are slightly worse. The humidity forecasts are improved most. For precipitation forecasts, the DR 3DEnVar always outperforms HR GSI 3DVar. It also outperforms the LR 3DEnVar, except for the initial forecast period and lower thresholds.

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....

10 CFR 707.13 - Medical review of results of tests for illegal drug use.

Science.gov (United States)

2010-01-01

... another test, performed by the gas chromatography/mass spectrometry method (GC/MS). This procedure is... 10 Energy 4 2010-01-01 2010-01-01 false Medical review of results of tests for illegal drug use... Procedures § 707.13 Medical review of results of tests for illegal drug use. (a) All test results shall be...

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...

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 ).

Deuteriation of an asymmetric short hydrogen bond. X-ray crystal structure of KF.(CH2CO2D)2

International Nuclear Information System (INIS)

Emsley, J.; Jones, D.J.; Kuroda, R.

1981-01-01

Deuteriation of the strong hydrogen bonds of KF.(CH 2 CO 2 H) 2 shows no isotope effect on the bond lengths. The only significant change is in the bond angle at the fluoride ion which widens to 128.5 from 116 0 . The i.r. spectrum shows very little change. Since the O-H ... F - hydrogen bonds are highly asymmetric, these observations challenge previous predictions about the effects of deuteriation on such bonds. (author)

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

EnKF OSSE Experiments Assessing the Impact of HIRAD Wind Speed and HIWRAP Radial Velocity Data on Analysis of Hurricane Karl (2010)

Science.gov (United States)

Albers, Cerese; Sippel, Jason A.; Braun, Scott A.; Miller, Timothy

2012-01-01

Previous studies (e.g., Zhang et al. 2009, Weng et al. 2011) have shown that radial velocity data from airborne and ground-based radars can be assimilated into ensemble Kalman filter (EnKF) systems to produce accurate analyses of tropical cyclone vortices, which can reduce forecast intensity error. Recently, wind speed data from SFMR technology has also been assimilated into the same types of systems and has been shown to improve the forecast intensity of mature tropical cyclones. Two instruments that measure these properties were present during the NASA Genesis and Rapid Intensification Processes (GRIP) field experiment in 2010 which sampled Hurricane Karl, and will next be co-located on the same aircraft for the subsequent NASA HS3 experiment. The High Altitude Wind and Rain Profiling Radar (HIWRAP) is a conically scanning Doppler radar mounted upon NASAs Global Hawk unmanned aerial vehicle, and the usefulness of its radial velocity data for assimilation has not been previously examined. Since the radar scans from above with a fairly large fixed elevation angle, it observes a large component of the vertical wind, which could degrade EnKF analyses compared to analyses with data taken from lesser elevation angles. The NASA Hurricane Imaging Radiometer (HIRAD) is a passive microwave radiometer similar to SFMR, and measures emissivity and retrieves hurricane surface wind speeds and rain rates over a much wider swath. Thus, this study examines the impact of assimilating simulated HIWRAP radial velocity data into an EnKF system, simulated HIRAD wind speed, and HIWRAP+HIRAD with the Weather Research and Forecasting (WRF) model and compares the results to no data assimilation and also to the Truth from which the data was simulated for both instruments.

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...

Impact of an indigenous microbial enhanced oil recovery field trial on microbial community structure in a high pour-point oil reservoir

Energy Technology Data Exchange (ETDEWEB)

Zhang, Fan; Zhang, Xiao-Tao; Hou, Du-Jie [China Univ. of Geosciences, Beijing (China). The Key Lab. of Marine Reservoir Evolution and Hydrocarbon Accumulation Mechanism; She, Yue-Hui [Yangtze Univ., Jingzhou, Hubei (China). College of Chemistry and Environmental Engineering; Huazhong Univ. of Science and Technology, Wuhan (China). College of Life Science and Technology; Li, Hua-Min [Beijing Bioscience Research Center (China); Shu, Fu-Chang; Wang, Zheng-Liang [Yangtze Univ., Jingzhou, Hubei (China). College of Chemistry and Environmental Engineering; Yu, Long-Jiang [Huazhong Univ. of Science and Technology, Wuhan (China). College of Life Science and Technology

2012-08-15

Based on preliminary investigation of microbial populations in a high pour-point oil reservoir, an indigenous microbial enhanced oil recovery (MEOR) field trial was carried out. The purpose of the study is to reveal the impact of the indigenous MEOR process on microbial community structure in the oil reservoir using 16Sr DNA clone library technique. The detailed monitoring results showed significant response of microbial communities during the field trial and large discrepancies of stimulated microorganisms in the laboratory and in the natural oil reservoir. More specifically, after nutrients injection, the original dominant populations of Petrobacter and Alishewanella in the production wells almost disappeared. The expected desirable population of Pseudomonas aeruginosa, determined by enrichment experiments in laboratory, was stimulated successfully in two wells of the five monitored wells. Unexpectedly, another potential population of Pseudomonas pseudoalcaligenes which were not detected in the enrichment culture in laboratory was stimulated in the other three monitored production wells. In this study, monitoring of microbial community displayed a comprehensive alteration of microbial populations during the field trial to remedy the deficiency of culture-dependent monitoring methods. The results would help to develop and apply more MEOR processes. (orig.)

Isolation, Characterization, and Genetic Diversity of Ice Nucleation Active Bacteria on Various Plants

Directory of Open Access Journals (Sweden)

DIANA ELIZABETH WATURANGI

2009-06-01

Full Text Available Ice nucleation active (INA bacteria is a group of bacteria with the ability to catalyze the ice formation at temperature above -10 °C and causing frost injury in plants. Since, most of the literature on INA bacteria were from subtropical area, studies of INA bacteria from tropical area are needed. We sampled eight fruits and 36 leaves of 21 plant species, and then identified through biochemical and genetic analysis. INA bacteria were characterized for INA protein classification, pH stability, and optimization of heat endurance. We discovered 15 INA bacteria from seven plants species. Most of bacteria are oxidase and H2S negative, catalase and citrate positive, gram negative, and cocoid formed. These INA bacteria were classified in to three classes based on their freezing temperature. Most of the isolates were active in heat and pH stability assay. Some isolates were analysed for 16S rRNA gene. We observed that isolates from Morinda citrifolia shared 97% similiarity with Pseudomonas sp. Isolate from Piper betle shared 93% similarity with P. pseudoalcaligenes. Isolate from Carica papaya shared 94% similarity with Pseudomonas sp. While isolate from Fragaria vesca shared 90% similarity with Sphingomonas sp.

Isolation, Characterization, and Genetic Diversity of Ice Nucleation Active Bacteria on Various Plants

Directory of Open Access Journals (Sweden)

DIANA ELIZABETH WATURANGI

2009-06-01

Full Text Available Ice nucleation active (INA bacteria is a group of bacteria with the ability to catalyze the ice formation at temperature above -10 oC and causing frost injury in plants. Since, most of the literature on INA bacteria were from subtropical area, studies of INA bacteria from tropical area are needed. We sampled eight fruits and 36 leaves of 21 plant species, and then identified through biochemical and genetic analysis. INA bacteria were characterized for INA protein classification, pH stability, and optimization of heat endurance. We discovered 15 INA bacteria from seven plants species. Most of bacteria are oxidase and H2S negative, catalase and citrate positive, gram negative, and cocoid formed. These INA bacteria were classified in to three classes based on their freezing temperature. Most of the isolates were active in heat and pH stability assay. Some isolates were analysed for 16S rRNA gene. We observed that isolates from Morinda citrifolia shared 97% similiarity with Pseudomonas sp. Isolate from Piper betle shared 93% similarity with P. pseudoalcaligenes. Isolate from Carica papaya shared 94% similarity with Pseudomonas sp. While isolate from Fragaria vesca shared 90% similarity with Sphingomonas sp.

Impact of an indigenous microbial enhanced oil recovery field trial on microbial community structure in a high pour-point oil reservoir.

Science.gov (United States)

Zhang, Fan; She, Yue-Hui; Li, Hua-Min; Zhang, Xiao-Tao; Shu, Fu-Chang; Wang, Zheng-Liang; Yu, Long-Jiang; Hou, Du-Jie

2012-08-01

Based on preliminary investigation of microbial populations in a high pour-point oil reservoir, an indigenous microbial enhanced oil recovery (MEOR) field trial was carried out. The purpose of the study is to reveal the impact of the indigenous MEOR process on microbial community structure in the oil reservoir using 16Sr DNA clone library technique. The detailed monitoring results showed significant response of microbial communities during the field trial and large discrepancies of stimulated microorganisms in the laboratory and in the natural oil reservoir. More specifically, after nutrients injection, the original dominant populations of Petrobacter and Alishewanella in the production wells almost disappeared. The expected desirable population of Pseudomonas aeruginosa, determined by enrichment experiments in laboratory, was stimulated successfully in two wells of the five monitored wells. Unexpectedly, another potential population of Pseudomonas pseudoalcaligenes which were not detected in the enrichment culture in laboratory was stimulated in the other three monitored production wells. In this study, monitoring of microbial community displayed a comprehensive alteration of microbial populations during the field trial to remedy the deficiency of culture-dependent monitoring methods. The results would help to develop and apply more MEOR processes.

Gaussian anamorphosis in the analysis step of the EnKF: a joint state-variable/observation approach

Directory of Open Access Journals (Sweden)

Javier Amezcua

2014-09-01

Full Text Available The analysis step of the (ensemble Kalman filter is optimal when (1 the distribution of the background is Gaussian, (2 state variables and observations are related via a linear operator, and (3 the observational error is of additive nature and has Gaussian distribution. When these conditions are largely violated, a pre-processing step known as Gaussian anamorphosis (GA can be applied. The objective of this procedure is to obtain state variables and observations that better fulfil the Gaussianity conditions in some sense. In this work we analyse GA from a joint perspective, paying attention to the effects of transformations in the joint state-variable/observation space. First, we study transformations for state variables and observations that are independent from each other. Then, we introduce a targeted joint transformation with the objective to obtain joint Gaussianity in the transformed space. We focus primarily in the univariate case, and briefly comment on the multivariate one. A key point of this paper is that, when (1–(3 are violated, using the analysis step of the EnKF will not recover the exact posterior density in spite of any transformations one may perform. These transformations, however, provide approximations of different quality to the Bayesian solution of the problem. Using an example in which the Bayesian posterior can be analytically computed, we assess the quality of the analysis distributions generated after applying the EnKF analysis step in conjunction with different GA options. The value of the targeted joint transformation is particularly clear for the case when the prior is Gaussian, the marginal density for the observations is close to Gaussian, and the likelihood is a Gaussian mixture.

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

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...

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)

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....

A hydroponic system for growing gnotobiotic vs. sterile plants to study phytoremediation processes.

Science.gov (United States)

Kurzbaum, E; Kirzhner, F; Armon, R

2014-01-01

In some phytoremediation studies it is desirable to separate and define the specific contribution of plants and root-colonizing bacteria towards contaminant removal. Separating the influence of plants and associated bacteria is a difficult task for soil root environments. Growing plants hydroponically provides more control over the biological factors in contaminant removal. In this study, a hydroponic system was designed to evaluate the role of sterile plant roots, rhizodeposition, and root-associated bacteria in the removal of a model contaminant, phenol. A strain of Pseudomonas pseudoalcaligenes that grows on phenol was inoculated onto plant roots. The introduced biofilm persisted in the root zone and promoted phenol removal over non-augmented controls. These findings indicate that this hydroponic system can be a valuable tool for phytoremediation studies that investigate the effects of biotic and abiotic factors on pollution remediation.

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.

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.

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.

Raman spectroscopic study of the minerals apophyllite-(KF) KCa4Si8O20F·8H2O and apophyllite-(KOH) KCa4Si8O20(F,OH)·8H2O

Science.gov (United States)

Frost, Ray L.; Xi, Yunfei

2012-11-01

Raman spectroscopy complimented with infrared spectroscopy has been used to study the variation in molecular structure of two minerals of the apophyllite mineral group, namely apophyllite-(KF) KCa4Si8O20F·8H2O and apophyllite-(KOH) KCa4Si8O20(F,OH)·8H2O. apophyllite-(KF) and apophyllite-(KOH) are different minerals only because of the difference in the percentage of fluorine to hydroxyl ions. The Raman spectra are dominated by a very intense sharp peak at 1059 cm-1. A band at around 846 cm-1 is assigned to the water librational mode. It is proposed that the difference between apophyllite-(KF) and apophyllite-(KOH) is the observation of two Raman bands in the OH stretching region at around 3563 and 3625 cm-1. Multiple water stretching and bending modes are observed showing that there is much variation in hydrogen bonding between water and the silicate surfaces.

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 ...

25 CFR 115.707 - Will the Secretary accept administrative fees for deposit into a trust account?

Science.gov (United States)

2010-04-01

... Information § 115.707 Will the Secretary accept administrative fees for deposit into a trust account? No. The Secretary will not accept administrative fees for deposit into a trust account because administrative fees... 25 Indians 1 2010-04-01 2010-04-01 false Will the Secretary accept administrative fees for deposit...

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....

26 CFR 1.707-5 - Disguised sales of property to partnership; special rules relating to liabilities.

Science.gov (United States)

2010-04-01

... 1.707-4, if a partnership assumes or takes property subject to a qualified liability (as defined in... liabilities, as defined in paragraph (a)(6) of this section) assumed or taken subject to by the partnership... 26 Internal Revenue 8 2010-04-01 2010-04-01 false Disguised sales of property to partnership...

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...

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...

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.

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...

Quantitative Analysis of KF-LiF-ZrF4 Molten Salt by Probe Assisted in-situ LIBS Systems

International Nuclear Information System (INIS)

Kim, S.H.; Moon, J.H.; Kim, D.H.; Hwang, I.S.; Lee, J.H.

2015-01-01

Full text of publication follows: Pyro-processing draws attention as a recycling process of spent nuclear fuel for future nuclear reactor. In the aspect of process control and safeguards of the pyro-processing, it requires a technology to measure the concentration of molten salt in real-time. The existing technologies measure the concentration by chemical analysis of sampled molten salt in the hot cell but it is disadvantageous in the aspects of cost, safety and time. The LIBS (Laser-Induced Breakdown Spectroscopy) is a form of atomic emission spectroscopy in which a pulsed laser is used as the excitation source. LIBS technology is appropriate to measure sensitive nuclear materials in hot cell because it is capable of measuring specimen quantitatively and qualitatively by exited atom by laser. Spectrum obtained from plasma is largely influenced by laser operation conditions and physical properties of specimens. Also, plasma induction is limited on the surface of specimen, so analysis of composition inside of the molten salt is extremely difficult. Thus, several restrictions should be overcome in order to apply LIBS for the measurement of molten salt (KF-LiF-ZrF 4 ) composition in real-time. In this study probe assisted LIBS system will be introduced with KF-LiF-ZrF 4 to quantitatively measure molten salt composition. Echelle spectrometer was used and the measurable wavelength area was 250-400 nm, the range of UV ray. NIST atomic spectra database measured the wavelength for molten salt composition, and each element was selected high signal intensity and wavelength range that is not overlapped by other elements. (authors)

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

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

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...

Status report. KfK contribution to the development of DEMO-relevant test blankets for NET/ITER. Pt. 1: Self-cooled liquid metal breeder blanket. Vol. 1

International Nuclear Information System (INIS)

Malang, S.; Reimann, J.; Sebening, H.; Barleon, L.; Bogusch, E.; Bojarsky, E.; Borgstedt, H.U.; Buehler, L.; Casal, V.; Deckers, H.; Feuerstein, H.; Fischer, U.; Frees, G.; Graebner, H.; John, H.; Jordan, T.; Kramer, W.; Krieg, R.; Lenhart, L.; Malang, S.; Meyder, R.; Norajitra, P.; Reimann, J.; Schwenk-Ferrero, A.; Schnauder, H.; Stieglitz, R.; Oschinski, J.; Wiegner, E.

1991-12-01

A self-cooled liquid metal breeder blanket for a fusion DEMO-reactor and the status of the development programme is described as a part of the European development programme of DEMO relevant test blankets for NET/ITER. Volume 1 (KfK 4907) contains a summary, Volume 2 (KfK 4908) a more detailed version of the report. Both volumes contain sections on previous studies on self-cooled liquid metal breeder blankets, the reference blanket design for a DEMO-reactor, a typical test blanket design including the ancillary loop system and the building requirements for NET/ITER together with the present status of the associated R and D-programme in the fields of neutronics, magnetohydrodynamics, tritium removal and recovery, liquid metal compatibility and purification, ancillary loop system, safety and reliability. An outlook is given regarding the required R and D-programme for the self-cooled liquid metal breeder blanket prior to tests in NET/ITER and the relevant test programme to be performed in NET/ITER. (orig.) [de

Short-Range prediction of a Mediterranean Severe weather event using EnKF: Configuration tests

Science.gov (United States)

Carrio Carrio, Diego Saul; Homar Santaner, Víctor

2014-05-01

The afternoon of 4th October 2007, severe damaging winds and torrential rainfall affected the Island of Mallorca. This storm produced F2-F3 tornadoes in the vicinity of Palma, with one person killed and estimated damages to property exceeding 10 M€. Several studies have analysed the meteorological context in which this episode unfolded, describing the formation of a train of multiple thunderstorms along a warm front and the evolution of a squall line organized from convective activity initiated offshore Murcia during that morning. Couhet et al. (2011) attributed the correct simulation of the convective system and particularly its organization as a squall line to the correct representation of a convergence line at low-levels over the Alboran Sea during the first hours of the day. The numerical prediction of mesoscale phenomena which initiates, organizes and evolves over the sea is an extremely demanding challenge of great importance for coastal regions. In this study, we investigate the skill of a mesoscale ensemble data assimilation system to predict the severe phenomena occurred on 4th October 2007. We use an Ensemble Kalman Filter which assimilates conventional (surface, radiosonde and AMDAR) data using the DART implementation from (NCAR). On the one hand, we analyse the potential of the assimilation cycle to advect critical observational data towards decisive data-void areas over the sea. Furthermore, we assess the sensitivity of the ensemble products to the ensemble size, grid resolution, assimilation period and physics diversity in the mesoscale model. In particular, we focus on the effect of these numerical configurations on the representation of the convective activity and the precipitation field, as valuable predictands of high impact weather. Results show that the 6-h EnKF assimilation period produces initial fields that successfully represent the environment in which initiation occurred and thus the derived numerical predictions render improved

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 ).

Multiscale KF Algorithm for Strong Fractional Noise Interference Suppression in Discrete-Time UWB Systems

Directory of Open Access Journals (Sweden)

Liyun Su

2011-01-01

Full Text Available In order to suppress the interference of the strong fractional noise signal in discrete-time ultrawideband (UWB systems, this paper presents a new UWB multi-scale Kalman filter (KF algorithm for the interference suppression. This approach solves the problem of the narrowband interference (NBI as nonstationary fractional signal in UWB communication, which does not need to estimate any channel parameter. In this paper, the received sampled signal is transformed through multiscale wavelet to obtain a state transition equation and an observation equation based on the stationarity theory of wavelet coefficients in time domain. Then through the Kalman filter method, fractional signal of arbitrary scale is easily figured out. Finally, fractional noise interference is subtracted from the received signal. Performance analysis and computer simulations reveal that this algorithm is effective to reduce the strong fractional noise when the sampling rate is low.

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)

Corrosion of superalloy Incoloy 800H/HT in eutectic mixture LiF-NaF-KF with different addition of chromium fluoride; Korozia superzliatiny Incoloy 800H/HT v eutektickej zmesi LiF-NaF-KF s ruznym pridavkom fluoridu chromiteho

Energy Technology Data Exchange (ETDEWEB)

Kontrik, M.; Pavlik, V.; Simko, F. [Slovenska Akademia Vied, Ustav Anorganickej Chemie, Oddelenie Taveninovych Sustav, 84636 Bratislava (Slovakia)

2013-04-16

Thesis deals with investigating the addition of chromium trifluoride to eutectic mixture of LiF-NaF-KF (46.5 - 11.5 - 42 mol %) on the corrosion of superalloy Incoloy 800H/HT with static tests. The corrosion losses of the alloy and type of corrosion attack was observed. It was found that the addition of chromium fluoride into the mixture generally increases of corrosion of the material. Several types of corrosion attacks were observed. On the surface of the samples the spotted, pitting and transgranular corrosions were found. On the cross-sections of the samples the subsurface and lamellar corrosions were detected. (authors)

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

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...

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

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

EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA); Scientific Opinion on the substantiation of a health claim related to KF2BL20 and maintenance of normal hair pursuant to Article 13(5) of Regulation (EC) No 1924/2006

DEFF Research Database (Denmark)

Tetens, Inge

and contributes to reduce hair loss”. The target population proposed by the applicant is healthy adults in the general population. The Panel considers that maintenance of normal hair is a beneficial physiological effect. The applicant identified one single arm study as being pertinent to the health claim...... related to KF2BL20, which is a combination of keratin, copper, zinc, niacin, pantothenic acid, pyridoxine and D-biotin, and maintenance of normal hair. The Panel considers that KF2BL20 is sufficiently characterised. The claimed effect is “helps to reinforce hair strength and normal hair function....... The Panel notes that this study was uncontrolled and considers that no conclusions can be drawn from this study for the scientific substantiation of the claim. The Panel concludes that a cause and effect relationship has not been established between the consumption of KF2BL20 and maintenance of normal hair....

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.

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.

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 ...

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

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.).

Omega Air 707/F/A-18A-D Aerial Refueling Ground and Flight Test Evaluation and MA-3-1 Coupling Ground Test Evaluation

National Research Council Canada - National Science Library

Markowich, Brian

2001-01-01

Omega Air, Incorporated, a private organization that provides shipping and transportation services, contracted Marconi Flight Systems, Incorporated, to retrofit a Boeing 707 aircraft with an internal...

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, ...

Status report. KfK contribution to the development of DEMO-relevant test blankets for NET/ITER. Pt. 1: Self-cooled liquid metal breeder blanket. Vol. 2. Detailed version

International Nuclear Information System (INIS)

John, H.; Malang, S.; Sebening, H.

1991-12-01

A self-cooled liquid metal breeder blanket for a fusion DEMO-reactor and the status of the development programme is described as a part of the European development programme of DEMO relevant test blankets for NET/ITER. Volume 1 (KfK 4907) contains a summary. Volume 2 (KfK 4908) a more detailed version of the report. Both volumes contain sections on previous studies on self-cooled liquid metal breeder blankets, the reference blanket design for a DEMO-reactor, a typical test blanket design including the ancillary loop system and the building requirements for NET/ITER together with the present status of the associated RandD-programme in the fields of neutronics, magnetohydrodynamics, tritium removal and recovery, liquid metal compatibility and purification, ancillary loop system, safety and reliability. An outlook is given regarding the required RandD-programme for the self-cooled liquid metal breeder blanket prior to tests in NET/ITER and the relevant test programme to be performed in NET/ITER. (orig.) [de

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.

Electrochemical behaviours of lanthanide fluorides in the electrolysis system with LiF-NaF-Kf salt

International Nuclear Information System (INIS)

Joon-Bo, Shim; Sung-Chan, Hwang; Eung-Ho, Kim; Young-Ho, Kang; Byung-Jik, Lee; Jae-Hyung, Yoo

2003-01-01

As a part of partitioning studies, the experiments of cyclic voltammetry and electrolytic reduction with the liquid bismuth cathode were conducted to investigate electrochemical behaviours of lanthanide elements in the electrorefining system employing LiF-NaF-KF eutectic salt as the electrolyte. The cyclic voltammograms for NdF 3 and GdF 3 were obtained at various potential scan rates, respectively. The cathodic and anodic peak currents of the elements increased in proportion to the square root of the potential scan rate. According to changes of the potential difference between the coupled cathodic and anodic peaks, reversibilities of the reduction-oxidation reactions in this system were evaluated. In addition, further behaviours of electrochemical reaction of the elements were examined through electrolytic tests of the system using liquid bismuth as the cathode at fixed current densities. (author)

Variation analysis of bacterial polyhydroxyalkanoates production using saturated and unsaturated hydrocarbons

Directory of Open Access Journals (Sweden)

Saiqa Tufail

Full Text Available ABSTRACT Polyhydroxyalkanoates (PHA are efficient, renewable and environment friendly polymeric esters. These polymers are synthesized by a variety of microbes under stress conditions. This study was carried out to check the suitability of waste frying oil in comparison to other oils for economical bioplastic production. Six bacterial strains were isolated and identified as Bacillus cereus (KF270349, Klebsiella pneumoniae (KF270350, Bacillus subtilis (KF270351, Brevibacterium halotolerance (KF270352, Pseudomonas aeruginosa (KF270353, and Stenotrophomonas rhizoposid (KF270354 by ribotyping. All strains were PHA producers so were selected for PHA synthesis using four different carbon sources, i.e., waste frying oil, canola oil, diesel and glucose. Extraction of PHA was carried out using sodium hypochlorite method and maximum amount was detected after 72 h in all cases. P. aeruginosa led to maximum PHA production after 72 h at 37 °C and 100 rpm using waste frying oil that was 53.2% PHA in comparison with glucose 37.8% and cooking oil 34.4%. B. cereus produced 40% PHA using glucose as carbon source which was high when compared against other strains. A significantly lesser amount of PHA was recorded with diesel as a carbon source for all strains. Sharp Infrared peaks around 1740-1750 cm-1 were present in Fourier Transform Infrared spectra that correspond to exact position for PHA. The use of waste oils and production of poly-3hydroxybutyrate-co-3hydroxyvalerate (3HB-co-3HV by strains used in this study is a good aspect to consider for future prospects as this type of polymer has better properties as compared to PHBs.

33 CFR 148.707 - What type of criteria will be used in an environmental review and how will they be applied?

Science.gov (United States)

2010-07-01

...: GENERAL Environmental Review Criteria for Deepwater Ports § 148.707 What type of criteria will be used in... patterns; (3) The potential risks to a deepwater port from waves, winds, weather, and geological conditions... children from environmental health and safety risks. ...

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 ...

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.

Thermodynamic Assessment of Hot Corrosion Mechanisms of Superalloys Hastelloy N and Haynes 242 in Eutectic Mixture of Molten Salts KF and ZrF4

Energy Technology Data Exchange (ETDEWEB)

Michael V. Glazoff

2012-02-01

The KF - ZrF4 system was considered for the application as a heat exchange agent in molten salt nuclear reactors (MSRs) beginning with the work carried out at ORNL in early fifties. Based on a combination of excellent properties such as thermal conductivity, viscosity in the molten state, and other thermo-physical and rheological properties, it was selected as one of possible candidates for the nuclear reactor secondary heat exchanger loop.

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...

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)

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.

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...

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...

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

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.

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.

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.

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

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.

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.

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.

[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.

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...

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.

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.

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

Green Michael addition of thiols to electron deficient alkenes using KF/alumina and recyclable solvent or solvent-free conditions

Energy Technology Data Exchange (ETDEWEB)

Lenardao, Eder J.; Trecha, Danusia O.; Ferreira, Patricia da C.; Jacob, Raquel G.; Perin, Gelson [Universidade Federal de Pelotas (UFPEL), Pelotas, RS (Brazil). Inst. de Quimica e Geociencias. Lab. de Sintese Organica Limpa (LASOL)]. E-mail: lenardao@ufpel.edu.br

2009-07-01

A general, clean and easy method for the conjugated addition of thiols to citral promoted by KF/Al{sub 2}O{sub 3} under solvent-free or using glycerin as recyclable solvent at room temperature is described. It was found that the solvent-free protocol is applicable to the direct reaction of thiophenol with the essential oil of lemon grass (Cymbopogon citratus) to afford directly 3,7-dimethyl-3-(phenylthio)oct-6-enal, a potential bactericide agent. The method was extended to other electron-poor alkenes with excellent results. For the solvent-free protocol, the use of microwave irradiation facilitated the procedure and accelerates the reaction. The catalytic system and glycerin can be reused up to three times without previous treatment with comparable activity. (author)

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.

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

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.

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.

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.

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...

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

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.

Nuclear Fusion Project. Semi-annual report of the Association KfK/EURATOM

International Nuclear Information System (INIS)

Kast, G.

1989-04-01

Report on technology tasks: Blanket design studies; development of computational tools for neutronics; corrosion and fatigue of structural materials in flowing Pb-17Li; tritium extraction from liquid Pb-17Li by the use of solid getters; ceramic breeder materials; high field composite conductors; superconducting poloidal field coil development; design and construction of a poloidal field coil for TORE SUPRA as NET-prototype coil; structural materials fatigue characterization at 4 K; low electrical conductivity structural development; MANET 1; pre- and post-irradiation fatigue properties of 1.4914 martensitic steel; in-pile creep-fatigue testing of type 316 and 1.4914 steel; ceramics for first-wall protection and for RF windows; fatigue under dual beam irradiation; low activation ferritic-martensitic steels; plasma facing components; procedures and tools for structural design evaluation; remote maintenance; mechanical component assembly; handling equipment for in-vessel components; safety aspects of the cryosystem and of superconducting magnets; safety guidelines for the design of NET; generic environmental impact assessment for a fusion facility; large components for plasma exhaust pumping; optimization of cryogenic vacuum pumping of He; solid particle separators for plasma exhaust; plasma exhaust purification; adsorption of DT on heated metal beds other than U; catalyst development for the exhaust purification process; ECRH power sources; vacuum and exhaust performance of NET; NET TF pancake tests; CAD DATA exchange between NET and KfK; catalytic plasma exhaust gas clean-up facility for NET; NET blanket handling device; electrical connectors for remote handling. (orig./HP)

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.

[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.

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.

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.

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.

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.

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

Seismic and wind upgrade of buildings 707A and 779 at Rocky Flats Plant

International Nuclear Information System (INIS)

Siler, S.V.; Hom, S.; McGovern, L.J.; Terkun, V.

1991-01-01

The structural upgrade of two existing facilities at the US Department of Energy Rocky Flats Plant site has recently been completed. Two existing critical buildings were strengthened to enable them to withstand the design basis earthquake (DBE) forces and the design basis wind (DBW) forces without breach of containment. These buildings were constructed in the 1960s, with minimal seismic considerations. Building 707A is a two-story structure of precast concrete elements with cast-in-place topping slabs with 27,000 sq. feet of floor space. Building 779 is a two-story original structure and several additions, with floor space of 64,000 sq. feet. The original structure consists of cast-in-place concrete with masonry infill shear walls. The additions are primarily precast concrete with unreinforced masonry infill walls. The DBE was the maximum credible event with a magnitude of 6.0 occurring 16 miles from the site. The evaluation criteria was generated spectra at bedrock with a horizontal zero period acceleration of 0.14g. Bedrock-to-ground soil amplification factors were used to evaluate the buildings. The buildings were also required to withstand the DBW of 161 mph. Because of constraints associated with working inside, the structural upgrades were mostly confined to exterior work. The modifications utilized the existing roof and floor diaphragms, and primarily consisted of large exterior concrete buttresses and associated steel chords and collectors. A system of steel strongbacks was also used in some locations. Connections between precast elements of Building 707A had to be strengthened for ductility and shear transfer. The significance of this work is the successful implementation of a highly complex and comprehensive design retrofit of two very critical and important facilities, allowing for continued operation and minimal impact, and using practical and overall cost-effective strengthening schemes

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)

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.

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

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

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.

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...

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

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....

Electrochemical separation of uranium in the molten system LiF-NaF-KF-UF4

Science.gov (United States)

Korenko, M.; Straka, M.; Szatmáry, L.; Ambrová, M.; Uhlíř, J.

2013-09-01

This article is focused on the electrochemical investigation (cyclic voltammetry and related studies) of possible reduction of U4+ ions to metal uranium in the molten system LiF-NaF-KF(eut.)-UF4 that can provide basis for the electrochemical extraction of uranium from molten salts. Two-step reduction mechanism for U4+ ions involving one electron exchange in soluble/soluble U4+/U3+ system and three electrons exchange in the second step were found on the nickel working electrode. Both steps were found to be reversible and diffusion controlled. Based on cyclic voltammetry, the diffusion coefficients of uranium ions at 530 °C were found to be D(U4+) = 1.64 × 10-5 cm2 s-1 and D(U3+) 1.76 × 10-5 cm2 s-1. Usage of the nickel spiral electrode for electrorefining of uranium showed fairly good feasibility of its extraction. However some oxidant present during the process of electrorefining caused that the solid deposits contained different uranium species such as UF3, UO2 and K3UO2F5.

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.

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.

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.

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.

Uji produksi biosurfaktan oleh Pseudomonas sp. pada substrat yang berbeda

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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.

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.

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.

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.

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)).

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...

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 ...

An insulin receptor mutant (Asp707 → Ala), involved in leprechaunism, is processed and transported to the cell surface but unable to bind insulin

NARCIS (Netherlands)

L.M. 't Hart (Leen); D. Lindhout (Dick); G.C.M. van der Zon (Gerard); H. Kayserilli (Hülya); M.Y. Apak (Memnune); W.J. Kleijer (Wim); E.R. van der Vorm (Eric); J.A. Maassen (Johannes)

1996-01-01

textabstractWe have identified a homozygous mutation near the carboxyl terminus of the insulin receptor (IR) α subunit from a leprechaun patient, changing Asp707 into Ala. Fibroblasts from this patient had no high affinity insulin binding sites. To examine the effect of the mutation on IR

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...

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).

PseudoMLSA: a database for multigenic sequence analysis of Pseudomonas species

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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

KfK-analysis of the SUPER-PHENIX-1 control rod experiments. Pt. 2

International Nuclear Information System (INIS)

Giese, H.

1992-10-01

Using standard data and codes, this first analysis campaign led to results that drastically overestimated measured control rod worths with C/E ratios ranging from 1.17 to 1.28. These findings were in sharp contrast to the results of the majority of earlier control rod experiments in zero-power facilities, where C/E ratios were usually comprised between 1.0 and 1.1. Investigations were then launched to identify the origin of this discrepancy. By comparison with the calculation methods employed by the other working groups engaging in the analysis of the SPX-1 experiments it was found that the principal problem arose from the KfK/BN-procedure used for the homogenization of control rod absorber cross sections. The specific failure of this standard procedure in the case of the SPX-1 analysis is ascribed to the extremely heterogeneous structure of the SPX-1 control rods. In an attempt to improve on this point, a new method for the production of homogenized absorber cross sections was developed and applied to the SPX-1 analysis. The report concludes with a description of this method and a survey of the results obtained for SPX-1. It is found that this revised analysis leads to a significantly improved agreement of measured and calculated control rod worths and to a better consistency with the results of earlier control rod experiments in zero-power facilities. (orig.)

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.

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.

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, ...

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.

Biotransformation of Tributyltin chloride by Pseudomonas stutzeri strain DN2

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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.

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

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...

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

Ethanol production from kitchen waste using the flocculating yeast Saccharomyces cerevisiae strain KF-7

International Nuclear Information System (INIS)

Tang, Y.-Q.; Koike, Yoji; Liu Kai; An, M.-Z.; Morimura, Shigeru; Wu Xiaolei; Kida, Kenji

2008-01-01

A process for producing ethanol from kitchen waste was developed in this study. The process consists of freshness preservation of the waste, saccharification of the sugars in the waste, continuous ethanol fermentation of the saccharified liquid, and anaerobic treatment of the saccharification residue and the stillage. Spraying lactic acid bacteria (LCB) on the kitchen waste kept the waste fresh for over 1 week. High glucose recovery (85.5%) from LCB-sprayed waste was achieved after saccharification using Nagase N-40 glucoamylase. The resulting saccharified liquid was used directly for ethanol fermentation, without the addition of any nutrients. High ethanol productivity (24.0 g l -1 h -1 ) was obtained when the flocculating yeast strain KF-7 was used in a continuous ethanol fermentation process at a dilution rate of 0.8 h -1 . The saccharification residue was mixed with stillage and treated in a thermophilic anaerobic continuous stirred tank reactor (CSTR); a VTS loading rate of 6 g l -1 d -1 with 72% VTS digestion efficiency was achieved. Using this process, 30.9 g ethanol, and 65.2 l biogas with 50% methane, was produced from 1 kg of kitchen waste containing 118.0 g total sugar. Thus, energy in kitchen waste can be converted to ethanol and methane, which can then be used as fuels, while simultaneously treating kitchen waste

Ethanol production from kitchen waste using the flocculating yeast Saccharomyces cerevisiae strain KF-7

Energy Technology Data Exchange (ETDEWEB)

Tang, Yue-Qin; Liu, Kai; An, Ming-Zhe; Morimura, Shigeru; Kida, Kenji [Graduate School of Science and Technology, Kumamoto University, 2-39-1 Kurokami, Kumamoto 860-8555 (Japan); Koike, Yoji [Tokyo Gas Co., Ltd., 1-7-7 Suehiro-cho, Tsurumi-ku, Yokohama City, Kanagawa 230-0045 (Japan); Wu, Xiao-Lei [Department of Energy and Resources Engineering, College of Engineering, Peking University, Beijing 100871 (China)

2008-11-15

A process for producing ethanol from kitchen waste was developed in this study. The process consists of freshness preservation of the waste, saccharification of the sugars in the waste, continuous ethanol fermentation of the saccharified liquid, and anaerobic treatment of the saccharification residue and the stillage. Spraying lactic acid bacteria (LCB) on the kitchen waste kept the waste fresh for over 1 week. High glucose recovery (85.5%) from LCB-sprayed waste was achieved after saccharification using Nagase N-40 glucoamylase. The resulting saccharified liquid was used directly for ethanol fermentation, without the addition of any nutrients. High ethanol productivity (24.0 g l{sup -1} h{sup -1}) was obtained when the flocculating yeast strain KF-7 was used in a continuous ethanol fermentation process at a dilution rate of 0.8 h{sup -1}. The saccharification residue was mixed with stillage and treated in a thermophilic anaerobic continuous stirred tank reactor (CSTR); a VTS loading rate of 6 g l{sup -1} d{sup -1} with 72% VTS digestion efficiency was achieved. Using this process, 30.9 g ethanol, and 65.2 l biogas with 50% methane, was produced from 1 kg of kitchen waste containing 118.0 g total sugar. Thus, energy in kitchen waste can be converted to ethanol and methane, which can then be used as fuels, while simultaneously treating kitchen waste. (author)

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...

Electron Stimulated Molecular Desorption of a NEG St 707 at Room Temperature

CERN Document Server

Le Pimpec, F; Laurent, Jean Michel

2001-01-01

Electron stimulated molecular desorption (ESD) from a NEG St 707 (SAES GettersTM) sample after conditioning and after saturation with isotopic carbon monoxide2,13C18O, has been studied on a laboratory setup. Measurements were performed using an electron beam of 300 eV kinetic energy, with an average electron intensity of 1.6 1015 electrons s-1. The electrons were impinging on the 15 cm2 target surface at perpendicular incidence. It is found that the desorption yields h (molecules/electron) of the characteristic gases in an UHV system (hydrogen, methane, water, carbon monoxide, carbon dioxide) for a fully activated NEG as well as for a NEG fully saturated with 13C18O are lower than for OFHC copper baked at 120oC. A small fraction only of the gas which is required to saturate the getter surface can be re-desorbed and thus appears to be accessible to ESD.

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...

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.

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)).

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.

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.

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.

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.

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 ...

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...

User's guide for the portable microprocessor equipment: 'KfK K-edge densitometer' for quantitative determination of Th, U, Np, Pu, Am in solutions

International Nuclear Information System (INIS)

Michel-Piper, I.; Matussek, P.

1985-06-01

This report describes the hardware and software features, and the use of the microprocessor-controlled multichannel analyzer system SILENA + IRIS. The self-contained portable system, which permits independent accumulation and evaluation of spectral data from the KfK K-edge densitometer, provides one of the possible means for the authentication of resident instruments by safeguards inspectors. The 'K-Edge' program, written in PL/M language for compatibility with the system's firmware, allows fully automated assays of heavy element concentrations in solutions by means of X-ray absorption edge spectrometry. It is primarily intended for highly accurate determinations of the U and Pu content in process- and product solutions of a reprocessing plant. (orig.)

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....

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...

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

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

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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

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 ...

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...

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.

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

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.

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.

[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.

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

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 ...

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 ...

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...

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.

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.

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.

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 ...

Detection of extended spectrum β-lactamase in Pseudomonas spp. isolated from two tertiary care hospitals in Bangladesh

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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.

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

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.

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

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.

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

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....

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 ...

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

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)

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.

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.

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.

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

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.

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.

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 ...

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

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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

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] ...

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.

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.

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 ...

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 ...

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 ...

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...

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

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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.

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.

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

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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.

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

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

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 ...

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.

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

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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.

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.

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.

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.

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).

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...

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.

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

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%.

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

Rainfall Simulations of Typhoon Morakot with Controlled Translation Speed Based on EnKF Data Assimilation

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Tzu-Hsiung Yen

2011-01-01

Full Text Available Typhoon Morakot produced record-breaking accumulated rainfall over southern Taiwan in August 2009. The combination of several factors resulted in this extreme weather event: the steep terrain in Taiwan, the prevailing south-westerly flow in the monsoon trough, Typhoon Goni over the northern South China Sea, and the slow translation speed of Morakot itself over Taiwan. In this study, the influence of the translation speed is particularly emphasized. Based on the EnKF data assimilation, an innovative method is applied to perform ensemble simulations with several designated translation speeds of Morakot using the WRF model. Thus the influence of the translation speed on the amount of accumulated rainfall over Taiwan can be quantitatively evaluated. In the control simulation with observed translation speed, the maximum amount and geographic pattern of accumulated rainfall during the landfall period of Morakot are generally consistent with the observations, though the detailed overall distributions of accumulated rainfall is mostly underestimated, resulting in the low bias of the frequency distribution of the accumulated rainfall. In a simulation with nearly-doubled translation speed of Morakot, the maximum accumulated rainfall is decreased by 33% than that in the control simulation, while the rainfall distribution over Taiwan remains similar. In addition, the 28 ensemble members can further provide additional information in terms of their spread and other statistics. The results from ensemble members reveal the usefulness of ensemble simulations for the quantitative precipitation forecast.

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 ...

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...

Diversity of Aquatic Pseudomonas Species and Their Activity against the Fish Pathogenic Oomycete Saprolegnia.

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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.

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.

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

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

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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

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

Assessment of Risk Factors, Treatment and Hospital Stay in Complicated Urinary Tract Infections in Men Caused by Pseudomonas: A Case-Control Study

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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.

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...

Effective Biosurfactants Production by Pseudomonas aeruginosa and its Efficacy on Different Oils

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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.

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 ...

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...

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 ...

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...

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....

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...

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.

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.

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...

Elaboration and experimental study of the Borosilicate glass GP 98/12 for the vitrification of the radioactive wastes of KfKarlsruhe Centre (R.F.A.)

International Nuclear Information System (INIS)

Ghezal, A.

1987-09-01

The transformation into a vitrified block of highly radioactive liquid wastes is actually the best solution for the storage in long run. In West Germany, the research institute in the field of nuclear energy (KfK) has been oriented in this way by developing industrial processes of vitrification and by following studies on the behaviour of the final products. For the fission products, the chosen glasses present good stability characteristics and are used as a first barrier during confinement. Our work, which is part of the research program on radioactive waste vitrification, consists of preparing borosilicate glass GP 98/12 and studying physical and chemical characteristics. We have also contributed to the development and the realization of glass blocks sampling system prepared at pilot scale

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

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.

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

Far from superficial: microbial diversity associated with the skin and mucus of fish

Science.gov (United States)

Cipriano, Rocco C.; Dove, Alistair; Cipriano, R.C.; Bruckner, A.W.; Shchelkunov, I.S.

2011-01-01

During horizontal or water-borne infection involving an obligate pathogen (e.g. – Aeromonas salmonicida, cause of furunculosis), the pathogen interacted with and influenced the microbial diversity of the dermal mucus of fish. Prior to infection, the prevalent bacterial flora cultured from juvenile Atlantic salmon (Salmo salar) included Pseudomonas fluorescens, Comomonas terrigenia, Acinetobacter sp., Moraxella sp., Pseudomonas dimunita, Alcaligenes denitrificans, Pseudomonas pseudoalcaligenes, and Pseudomonas alcaligenes, Serratia liquefaciens, Aeromonas hydrophila, other motile Aeromonas spp., and Corynebacterium aquaticum. After A. salmonicida was initially detected in this population as an external mucus infection, Acinetobacter sp., Moraxella sp., C. terrigenia, P. fluorescens, and P. dimunita, Staphylococcus sp., and A. hydrophila, were also present in appreciable numbers. Within several weeks, however, the A. salmonicida infection amplified and composed 78% of the total flora in the mucus. Only P. dimunita (4%). P. fluorescens (2%), and C. terrigenia (1%) were cultured at that time and more than a third of these fish showed evidence of a systemic A. salmonicida infection within their kidneys. Eight weeks after oral oxytetracycline treatments, A. salmonicida was no longer isolated from the mucus or kidneys of any fish and glucose inert or other oxidative microbes (e.g., P. fluorescens, C. terrigenia, Acinetobacter sp., Moraxella sp.) were beginning to repopulate the external surface of the salmon in increasing frequency. Still present and composing fairly large percentages of the total flora were A. hydrophila, as well as Enterobacter sp., and P. putrefaciens. A normal microbial diversity was re-established as the fish recovered. In another investigation, reduced biological diversity was noted in the dermal mucus among smallmouth bass that were sampled from the Jackson River (Covington, VA). In these fish, A. hydrophila and P. putrefaciens were the two

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

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.

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.

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.

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.

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

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.

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 ...

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.

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

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

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

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.

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...

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.

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.

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...

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

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 ...

Decrease of Pseudomonas aeruginosa biofilm formation by food waste materials

Czech Academy of Sciences Publication Activity Database

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

2016-01-01

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

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

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.

Simple screening tests for the detection of metallo-β-lactamase (MBL production in clinical isolates of Pseudomonas and Acinetobacter

Directory of Open Access Journals (Sweden)

Shaheda Anwar

2010-01-01

Full Text Available There are no standard methods for the detection of metallo-b-lactamase (MBL production in gram negative organism in routine microbiology practice. The present study was undertaken to evaluate the screening tests like double disk synergy test (DDST and disk potentiation test (DPT using ceftazidime (CAZ and imipenem (IPM disks with chelating agents like EDTA, 2-mercaptopropionic acid (2-MPA. A total of 132 Pseudomonas and 76 Acinetobacter isolates were obtained from Bangabandhu Sheikh Mujib Medical University (BSMMU and Bangladesh Institute of Research and Rehabilitation for Diabetes, Endocrine and Metabolic Disorders (BIRDEM hospitals of Dhaka city. A total of 53 and 29 IPM resistant Pseudomonas and Acinetobacter isolates were selected. EDTA-IPM microdilution minimum inhibitory concentration (EDTA-IPM MIC method detected MBL in 44 (83% IPM resistant Pseudomonas and 19 (65.5% Acinetobacter isolates. DDST with CAZ-0.1M EDTA and CAZ-2-MPA detected MBL in 73.6% and 67.9% of IPM resistant Pseudomonas and 55.2% and 48.3% of Acinetobacter isolates respectively. The detection rate was 67.9% and 66.1% in Pseudomonas and 51.7% and 44.8% in Acinetobacter isolates by EDTA-IPM and IPM-2-MPA methods respectively. In comparison to DDST, DPT with CAZ-0.1M EDTA showed higher sensitivity (89.7% and specificity (100% for detection of MBL in Pseudomonas and Acinetobacter. The results showed that simple screening tests like DPT with 0.1M EDTA was able to detect MBL producing Pseudomonas and Acinetobacter from clinical samples with high sensitivity and specificity. Ibrahim Med. Coll. J. 2010; 4(1: 26-30

A biodegradable rubber by crosslinking poly(hydroxyalkanoate) from Pseudomonas oleovorans

NARCIS (Netherlands)

DEKONING, GJM; VANBILSEN, HMM; LEMSTRA, PJ; HAZENBERG, W; Witholt, B.; Preusting, H.; VANDERGALIEN, JG; SCHIRMER, A; JENDROSSEK, D

1994-01-01

Poly((R)-3-hydroxyalkanoate)s (PHAs) are bacterial storage polyesters, currently receiving much attention because of their potential application as biodegradable and biocompatible plastics. Among them are the PHAs from Pseudomonas oleovorans, which are semicrystalline elastomers. Their applicability

Production of bio surfactants (Rhamnolipids) by pseudomonas aeruginosa isolated from colombian sludges

International Nuclear Information System (INIS)

Pimienta, A.L; Diaz M, M. P; Carvajal S, F.G; Grosso V, J.L.

1997-01-01

The bio surfactant production by strains of Pseudomonas aeruginosa isolated from Colombian hydrocarbon contaminated sludge has been determined. The methodology included the isolation of microorganisms, standardization of batch culture conditions for good surfactant production and characterization of the produced rhamnolipid. Several carbon sources were evaluated with regard to the growth and production curves. The stability of the rhamnolipid was also determined under variable conditions of pH, temperature and salt concentration. The strain Pseudomonas aeruginosa BS 3 showed bio surfactant production capabilities of rhamnolipid resulting in concentrations up to 2 g-dm with surface tensions of 30 - 32 mN-m in batch cultures with commercial nutrients

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

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

Antimicrobial Activity of Various Plant Extracts on Pseudomonas Species Associated with Spoilage of Chilled Fish

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Osan Bahurmiz

2016-11-01

Full Text Available The antimicrobial activity of various plant extracts on Pseudomonas bacteria isolated from spoiled chilled tilapia (Oreochromis sp. was evaluated in this study. In the first stage of this study, red tilapia was subjected to chilled storage (4°C for 3 weeks, and spoilage bacteria were isolated and identified from the spoiled fish. Pseudomonas was the dominant bacteria isolated from the spoiled fish and further identification revealed that P. putida, P. fluorescens and Pseudomonas spp. were the main species of this group. In the second stage, methanolic extracts of 15 selected plant species were screened for their antimicrobial activity, by agar disc diffusion method, against the Pseudomonas isolates. Results indicated that most of the extracts had different degrees of activity against the bacterial isolates. The strongest activity was exhibited by bottlebrush flower (Callistemon viminalis extract. This was followed by extracts from guava bark (Psidium guajava and henna leaf (Lawsonia inermis. Moderate antimicrobial activities were observed in extracts of clove (Syzygium aromaticum, leaf and peel of tamarind (Tamarindus indica, cinnamon bark (Cinnamomum zeylanicum, wild betel leaf (Piper sarmentosum and fresh thyme (Thymus spp.. Weak or no antimicrobial activity was observed from the remaining extracts. The potential antimicrobial activity shown by some plant extracts in this study could significantly contribute to the fish preservation.

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

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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.

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

African Journals Online (AJOL)

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

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.

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.

Análisis transcriptómico y proteómico de Pseudomonas pseudoalcaligenes CECT5344 en respuesta a cianuro

OpenAIRE

Escribano Fernández, María de la Paz

2016-01-01

El cianuro es un compuesto natural muy tóxico para los seres vivos debido a su elevada afinidad por los metales, lo que provoca la inhibición de metaloenzimas, algunas de ellas esenciales para la vida. Además, esta afinidad del cianuro por los metales podría disminuir de la biodisponibilidad de algunos metales necesarios para procesos biológicos específicos. Muchos organismos son capaces de producir cianuro (cianogénesis), tolerarlo e incluso asimilarlo. Las plantas son la mayo...

The isolation and functional identification on producing cellulase of Pseudomonas mendocina

Science.gov (United States)

Zhang, Jianfeng; Hou, Hongyan; Chen, Guang; Wang, Shusheng; Zhang, Jiejing

2016-01-01

ABSTRACT The straw can be degraded efficiently into humus by powerful enzymes from microorganisms, resulting in the accelerated circulation of N,P,K and other effective elements in ecological system. We isolated a strain through screening the straw degradation strains from natural humic straw in the low temperature area in northeast of china, which can produce cellulase efficiently. The strain was identified as Pseudomonas mendocina by using morphological, physiological, biochemical test, and molecular biological test, with the functional clarification on producing cellulase for Pseudomonas mendocina for the first time. The enzyme force constant Km and the maximum reaction rate (Vmax) of the strain were 0.3261 g/L and 0.1525 mg/(min.L) through the enzyme activity detection, and the molecular weight of the enzyme produced by the strain were 42.4 kD and 20.4 kD based on SDS-PAGE. The effects of various ecological factors such as temperature, pH and nematodes on the enzyme produced by the strain in the micro ecosystem in plant roots were evaluated. The result showed that the optimum temperature was 28°C, and the best pH was 7.4∼7.8, the impact heavy metal was Pb2+ and the enzyme activity and biomass of Pseudomonas mendocina increased the movement and predation of nematodes. PMID:27710430

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.

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

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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.

Enriquecimiento diferencial de Pseudomonas spp. en el rizoplano de distintas especies cultivadas

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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.

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

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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.

Structural basis of the chiral selectivity of Pseudomonas cepacia lipase

NARCIS (Netherlands)

Lang, Dietmar A.; Mannesse, Maurice L.M.; Haas, Gerard H. de; Verheij, Hubertus M.; Dijkstra, Bauke W.

1998-01-01

To investigate the enantioselectivity of Pseudomonas cepacia lipase, inhibition studies were performed with S(c)-and R(c)-(R(p),S(p))-1,2-dialkylcarbamoylglycero-3-O-p-nitrophenyl alkylphosphonates of different alkyl chain lengths. P. cepacia lipase was most rapidly inactivated by

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...

Abundance and diversity of culturable Pseudomonas constitute sensitive indicators for adverse long-term copper impacts in soil

DEFF Research Database (Denmark)

Thorsen, Maja Kristine; Brandt, Kristian Koefoed; Nybroe, Ole

2013-01-01

heterotrophic bacteria. This indicates that the Pseudomonas population is not resilient towards copper stress and that culturable Pseudomonas spp. comprise sensitive bio-indicators of adverse copper impacts in contaminated soils. Further this study shows that copper exposure decreases bacterial diversity...

IDENTIFIKASI SURFAKTIN PADA PSEUDOMONAS FLUORESCENS ST1 PENGENDALI EFEKTIF PENYAKIT PUSTUL KEDELAI

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Suskandini Ratih Dirmawati .

2011-11-01

Full Text Available Identification of surfactin in Pseudomonas fluorescens ST1 which effectively suppres soybean bacterial pustule.   Identification of surfactin in Pseudomonas fluorescens ST1 filtrate was conducted in Plant Pest and Disease Laboratory, Bogor Agriculture University.  The 48 hours cultured suspension of  P. fluorescens ST1 with 108 CFU/ml density was centrifuged to obtain the supernatant.  The supernatant was analyzed for its surfactin content by High Performance Liquid Chromatography with Colum ODS-5 and eluen acetonitril and acetat acid.  The result showed  that  surfactin was producted by P. fluorescens ST1 and this bioactive substance could suppres the bacterial pustule on soybean.

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.

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)

Pseudomonas community structure and antagonistic potential in the rhizosphere : insights gained by combining phylogenetic and functional gene-based analyses

NARCIS (Netherlands)

Costa, Rodrigo; Gomes, Newton C. M.; Kroegerrecklenfort, Ellen; Opelt, Katja; Berg, Gabriele; Smalla, Kornelia

The Pseudomonas community structure and antagonistic potential in the rhizospheres of strawberry and oilseed rape (host plants of the fungal phytopathogen Verticillium dahliae) were assessed. The use of a new PCR-DGGE system, designed to target Pseudomonas-specific gacA gene fragments in

Eksperimentel bakteriofagterapi til behandling af kronisk Pseudomonas aeruginosaotitis hos hund

DEFF Research Database (Denmark)

Moodley, Arshnee; Mølgaard, Jesper

2016-01-01

Vi beskriver en case med anvendelsen af bakteriofager til behandling af kronisk otitis forårsaget af multiresistente Pseudomonas aeruginosa som en sidste behandlingsmulighed før aflivning. Trods gentagne behandlinger, både topikalt og systemisk, med op til seks forskellige antibiotika over en...

PAMDB: a comprehensive Pseudomonas aeruginosa metabolome database.

Science.gov (United States)

Huang, Weiliang; Brewer, Luke K; Jones, Jace W; Nguyen, Angela T; Marcu, Ana; Wishart, David S; Oglesby-Sherrouse, Amanda G; Kane, Maureen A; Wilks, Angela

2018-01-04

The Pseudomonas aeruginosaMetabolome Database (PAMDB, http://pseudomonas.umaryland.edu) is a searchable, richly annotated metabolite database specific to P. aeruginosa. P. aeruginosa is a soil organism and significant opportunistic pathogen that adapts to its environment through a versatile energy metabolism network. Furthermore, P. aeruginosa is a model organism for the study of biofilm formation, quorum sensing, and bioremediation processes, each of which are dependent on unique pathways and metabolites. The PAMDB is modelled on the Escherichia coli (ECMDB), yeast (YMDB) and human (HMDB) metabolome databases and contains >4370 metabolites and 938 pathways with links to over 1260 genes and proteins. The database information was compiled from electronic databases, journal articles and mass spectrometry (MS) metabolomic data obtained in our laboratories. For each metabolite entered, we provide detailed compound descriptions, names and synonyms, structural and physiochemical information, nuclear magnetic resonance (NMR) and MS spectra, enzymes and pathway information, as well as gene and protein sequences. The database allows extensive searching via chemical names, structure and molecular weight, together with gene, protein and pathway relationships. The PAMBD and its future iterations will provide a valuable resource to biologists, natural product chemists and clinicians in identifying active compounds, potential biomarkers and clinical diagnostics. © The Author(s) 2017. Published by Oxford University Press on behalf of Nucleic Acids Research.

Variation in hydrogen cyanide production between different strains of Pseudomonas aeruginosa

Czech Academy of Sciences Publication Activity Database

Gilchrist, F. J.; Alcock, A.; Belcher, J.; Brady, M.; Jones, A.; Smith, D.; Španěl, Patrik; Webb, K.; Lenney, W.

2011-01-01

Roč. 38, č. 2 (2011), s. 409-414 ISSN 0903-1936 Institutional research plan: CEZ:AV0Z40400503 Keywords : microbiology * pseudomonas aeruginosa Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 5.895, year: 2011

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.

WLIP, a lipodepsipeptide of Pseudomonas 'reactans', as inhibitor of the symptoms of the brown blotch disease of Agaricus bisporus

NARCIS (Netherlands)

Soler Rivas, C.; Arpin, N.; Olivier, J.M.; Wichers, H.J.

1999-01-01

A cell-free crude extract containing the white line inducing principle (WLIP), a lipodepsipeptide produced by Pseudomonas 'reactans', could inhibit browning of mushrooms caused by Pseudomonas tolaasii. Mushrooms inoculated with Ps. tolaasii at concentrations of 2.7 x 106 cfu ml-1 or higher showed

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

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

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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.

QUALIDADE BACTERIOLÓGICA DE OVOS CONTAMINADOS COM PSEUDOMONAS AERUGINOSA E ARMAZENADOS EM TEMPERATURA AMBIENTE OU REFRIGERADOS

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Fernanda Rodrigues Mendes

2014-12-01

Full Text Available The aim of this study was to evaluate the effect of sanitization and storage temperature on the quality of commercial eggs inoculated with Pseudomonas aeruginosa. We used 240 large eggs, without cracks, from Dekalb White laying hens at 30 to 40 weeks of age. The experimental design used was two blocks in a 2 x 2 factorial arrange (washed/non-washed and refrigerated/non-refrigerated with twelve replicates. The eggs were contaminated by handling, with 1.5 x 105 colony-forming units (CFU of Pseudomonas aeruginosa and stored at 5 °C and 25 °C for 30 days. Each ten days the eggshell and contents were submitted to bacteriological analyses. Variance analyses were performed and the data were compared by Tukey test. The results showed that Pseudomonas aeruginosa were isolated from the shells and contents of all eggs. Therefore, when the eggs were sanitized and stored at 5 ºC the contamination was less intense. The correlation between the presences of Pseudomonas aeruginosa in the shell and contents was high, when the eggs were not sanitized nor refrigerated. The conclusion of this study was that the egg must be sanitized and refrigerated when the stored for more than 30 days.

Purification and characterization of a chlorite dismutase from Pseudomonas chloritidismutans

NARCIS (Netherlands)

Mehboob, F.; Wolterink, A.F.W.M.; Vermeulen, A.J.; Jiang, B.; Hagedoorn, P.L.; Stams, A.J.M.; Kengen, S.W.M.

2009-01-01

The chlorite dismutase (Cld) of Pseudomonas chloritidismutans was purified from the periplasmic fraction in one step by hydroxyapatite chromatography. The enzyme has a molecular mass of 110 kDa and consists of four 31-kDa subunits. Enzyme catalysis followed Michaelis-Menten kinetics, with Vmax and

Induction of beta-lactamase production in Pseudomonas aeruginosa biofilm

DEFF Research Database (Denmark)

Giwercman, B; Jensen, E T; Høiby, N

1991-01-01

Imipenem induced high levels of beta-lactamase production in Pseudomonas aeruginosa biofilms. Piperacillin also induced beta-lactamase production in these biofilms but to a lesser degree. The combination of beta-lactamase production with other protective properties of the biofilm mode of growth c...... could be a major reason for the persistence of this sessile bacterium in chronic infections....

PSEUDOMONAS AERUGINOSA IN CHRONIC SUPPURATIVE OTITIS MEDIA- A DRUGSENSITIVITY STUDY

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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.

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.

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.

Differentiation of isolated native of desulphurizators Pseudomonas by means of the study of the profile of fatty acids

International Nuclear Information System (INIS)

Silva Gomez, Edelberto; Morales P, Alicia Lucia; Callejas Castro Solange; Florez Sandoval Maria Cecilia; Rodriguez Wilson

2000-01-01

The content of cellular fatty acids was determined by HRGC of twelve Colombian isolated Pseudomonas aeruginosa 17,18, 19, 20, 21, 22 and 103 pseudomonas sp 23,24,25,26 and 27 with desulphurization capacity, pseudomonas aeruginosa ATCC 9027 and 10145, pseudomonas sp ATCC 39327 and pseudomonas fluorescens. Fifty-three different types of fatty acids were found, among saturated and unsaturated of lineal chain, and mainly hydroxy acids and ramified. Of these, 17 have not been described in the literature for this genus. A group of 6 acids was presented with more frequency (15:0; 16:0; 16:1; 17:1; 3-OH 16:0 and 2-OH 15:0) in more than 75% of the pseudomonas studied. The studied microorganisms are related because they share the presence of some characteristic fatty acids, that which allows assuring that they belong to same taxonomic unit. The analysis cluster developed by means of plotting in dendrograms of the qualitative and quantitative contents of the acids fatty totals showed the formation of two attaches, the I conformed by ATCC 39327 and the isolated 17 and 25, and the II by Ps. Fluorescens and the isolated one 27. The dendrogram of the hydroxy acids shows the formation of four attaches, the I attache, (isolated 17 and 20), the II A (isolated 22 and 103), the II B (isolated 27 and ps. fluorescens) and the attache III (isolated 18 and 19). In that of the ramified fatty acids the formation of a main attache is observed conformed by four sub-groups, the IA (isolated 17), the I B (isolated 18 and 24), the I C (isolated 19 and 25 and Ps. fluorescens) and I D (isolated 27). These results show that the isolated 27,25,24, 19, 18 and 17, in their order, have narrow relationship to Ps. fluorescens

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

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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.

Convergent Metabolic Specialization through Distinct Evolutionary Paths in Pseudomonas aeruginosa

DEFF Research Database (Denmark)

La Rosa, Ruggero; Johansen, Helle Krogh; Molin, Søren

2018-01-01

fibrosis (CF) infection. In this work, we investigated how and through which trajectories evolution of Pseudomonas aeruginosa occurs when migrating from the environment to the airways of CF patients, and specifically, we determined reduction of growth rate and metabolic specialization as signatures...... of adaptive evolution. We show that central metabolic pathways of three distinct Pseudomonas aeruginosa lineages coevolving within the same environment become restructured at the cost of versatility during long-term colonization. Cell physiology changes from naive to adapted phenotypes resulted in (i......) alteration of growth potential that particularly converged to a slow-growth phenotype, (ii) alteration of nutritional requirements due to auxotrophy, (iii) tailored preference for carbon source assimilation from CF sputum, (iv) reduced arginine and pyruvate fermentation processes, and (v) increased oxygen...

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.

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.

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.

Phenotypic detection of metallo-β-lactamase among the clinical isolates of imipenem resistant Pseudomonas and Acinetobacter in tertiary care hospitals of Dhaka city

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Shaheda Anwar

2010-07-01

Full Text Available The rapid spread of Metallo-b-lactamase (MBL producing Gram negative bacilli represents a matter of great concern worldwide. The study analyzed the occurrence of MBL production in carbapenem resistant Pseudomonas and Acinetobacter isolates over one year period. A total of 132 Pseudomonas and 76 Acinetobacter isolates were obtained from two tertiary care hospitals of Dhaka city. A total of 53 Pseudomonas and 29 Acinetobacter isolates were selected because of their resistance to carbapenem specially imipenem (IPM. Screening for MBL production was performed in these isolates by IPM-EDTA microdilution MIC method. 44 (83% IPM resistant Pseudomonas and 19 (65.5% Acinetobacter isolates were MBL producer by IPM-EDTA microdilution MIC method. These results suggest that MBL producing Pseudomonas and Acinetobacter isolates are emerging in our country and it is essential to screen carbapenem resistant isolates for MBL production. Ibrahim Med. Coll. J. 2010; 4(2: 63-65

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

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.

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

Insights into catalytic action mechanism of Pseudomonas mendocina 3121-1 lipase

Czech Academy of Sciences Publication Activity Database

Bendikiene, V.; Surinenaite, B.; Juodka, B.; Šafaříková, Miroslava

2004-01-01

Roč. 34, - (2004), s. 572-577 ISSN 0141-0229 R&D Projects: GA AV ČR KSK4055109 Institutional research plan: CEZ:AV0Z6087904 Keywords : Pseudomonas mendocina * lipase Subject RIV: CE - Biochemistry Impact factor: 1.759, year: 2004

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...

Antibiotic and biosurfactant properties of cyclic lipopeptides produced by fluorescent Pseudomonas spp. from the sugar beet rhizosphere

DEFF Research Database (Denmark)

Nielsen, T.H.; Sørensen, D.; Tobiasen, C.

2002-01-01

Cyclic lipopeptides (CLPs) with antibiotic and biosurfactant properties are produced by a number of soil bacteria, including fluorescent Pseudomonas spp. To provide new and efficient strains for the biological control of root-pathogenic fungi in agricultural crops, we isolated approximately 600...... fluorescent Pseudomonas spp. from two different agricultural soils by using three different growth media. CLP production was observed in a large proportion of the strains (approximately 60%) inhabiting the sandy soil, compared to a low proportion (approximately 6%) in the loamy soil. Chemical structure...... in the peptide moiety. Production of specific CLPs could be affiliated with Pseudomonas fluorescens strain groups belonging to biotype I, V, or VI. In vitro analysis using both purified CLPs and whole-cell P. fluorescens preparations demonstrated that all CLPs exhibited strong biosurfactant properties...

Characterization of CMR5c and CMR12a, novel fluorescent Pseudomonas strains from the cocoyam rhizosphere with biocontrol activity

NARCIS (Netherlands)

Perneel, M.; Heyrman, J.; Adiobo, A.; Maeyer, de K.; Raaijmakers, J.M.; Vos, de P.; Höfte, M.

2007-01-01

Aim: To screen for novel antagonistic Pseudomonas strains producing both phenazines and biosurfactants that are as effective as Pseudomonas aeruginosa PNA1 in the biocontrol of cocoyam root rot caused by Pythium myriotylum. Material and Results: Forty pseudomonads were isolated from the rhizosphere

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

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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.

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.)

Management of root rot and root knot disease of mungbean with the application of mycorrhizospheric fluorescent pseudomonas under field condition

International Nuclear Information System (INIS)

Bokhari, S.S.; Tariq, S.; Ali, S.A.

2014-01-01

The mycorrhizosphere is the region around a mycorrhizal fungus in which nutrients released from the hyphae increases microbial population and its activities. In this study five mycorrhizospheric fluorescent Pseudomonas (MRFP) were evaluated for biocontrol potential under field condition using mungbean (Vigna radiata) as test plant. MRFP-249 significantly reduced Fusarium solani, Rhizoctonia solani and Macrophomina phaseolina. Whereas MRFP246 and MRFP-247 were also found effective against M. phaseolina. Mycorrhizospheric fluorescent Pseudomonas were also found effective against root knot nematode by reducing the galls on roots and nematode's penetration in roots. Highest fresh shoot weight and plant height was produced by MRFP-248. Plants grown in soil treated with Pseudomonas showed higher number of VAM spores around the mungbean roots than untreated control plants. The mycorrhizal symbiosis should not be considered merely as bipartite, plant-fungus interaction, but should instead include the associated microorganisms, particularly fluorescent Pseudomonas. (author)

Modulation of epithelial sodium channel (ENaC expression in mouse lung infected with Pseudomonas aeruginosa

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Radzioch Danuta

2005-01-01

Full Text Available Abstract Background The intratracheal instillation of Pseudomonas aeruginosa entrapped in agar beads in the mouse lung leads to chronic lung infection in susceptible mouse strains. As the infection generates a strong inflammatory response with some lung edema, we tested if it could modulate the expression of genes involved in lung liquid clearance, such as the α, β and γ subunits of the epithelial sodium channel (ENaC and the catalytic subunit of Na+-K+-ATPase. Methods Pseudomonas aeruginosa entrapped in agar beads were instilled in the lung of resistant (BalB/c and susceptible (DBA/2, C57BL/6 and A/J mouse strains. The mRNA expression of ENaC and Na+-K+-ATPase subunits was tested in the lung by Northern blot following a 3 hours to 14 days infection. Results The infection of the different mouse strains evoked regulation of α and β ENaC mRNA. Following Pseudomonas instillation, the expression of αENaC mRNA decreased to a median of 43% on days 3 and 7 after infection and was still decreased to a median of 45% 14 days after infection (p 1Na+-K+-ATPase mRNA, the catalytic subunit of the sodium pump, was recorded. The distinctive expression profiles of the three subunits were not different, between the susceptible and resistant mouse strains. Conclusions These results show that Pseudomonas infection, by modulating ENaC subunit expression, could influence edema formation and clearance in infected lungs.

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

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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.

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.

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

Diagnostic significance of measurements of specific IgG antibodies to Pseudomonas aeruginosa by three different serological methods

DEFF Research Database (Denmark)

Pressler, T.; Karpati, F.; Granstrom, M.

2008-01-01

to characterize patients with different infection status. Elevated levels of specific anti-Pseudomonas antibodies showed to be the risk factor for developing chronic Pa infection. Due to the specificity of the tests, antibiotic treatment based on serology might be considered in selected cases. There is a window...... of opportunity for suppression and eradication of initial P. aeruginosa infection making measurement of specific anti-Pseudomonas antibodies helpful Udgivelsesdato: 2009/1...

Within-host microevolution of Pseudomonas aeruginosa in Italian cystic fibrosis patients

DEFF Research Database (Denmark)

Marvig, Rasmus Lykke; Dolce, Daniela; Madsen Sommer, Lea Mette

2015-01-01

Chronic infection with Pseudomonas aeruginosa is a major cause of morbidity and mortality in cystic fibrosis (CF) patients, and a more complete understanding of P. aeruginosa within-host genomic evolution, transmission, and population genomics may provide a basis for improving intervention strate...

Pseudomonas aeruginosa with lasI quorum-sensing deficiency during corneal infection

DEFF Research Database (Denmark)

Zhu, H.; Bandara, R.; Conibear, T.C.

2004-01-01

To understand the importance of Pseudomonas aeruginosa quorum-sensing systems in the development of corneal infection, the genotypic characteristics and pathogenesis of seven ocular isolates with low-protease and acyl homoserine lactone (AHL) activity and quorum-sensing mutants of PAO1 deficient...

Antibacterial efficacies of some plant extracts against Aeromonas and Pseudomonas diseases of farmed catfish (Heterobranchus longifilis

Directory of Open Access Journals (Sweden)

Albert P. Ekanem

2011-11-01

Full Text Available Aeromonas and Pseudomonas diseases are responsible for mortalities of some farmed catfish in Nigeria. The objective of the study is to investigate the efficacies of extracts of some plants against Aeromonas and Pseudomonas diseases of Heterobranchus longifilis. Ethanol extracts of Phyllanthus amarus, Allium sativum, Artemisia annua, Citrus limon, Moringa oleifera, Allium cepa and Azadirachta indica were tested against Aeromonas hydrophila and Pseudomonas flourescens of H. longifilis by disc diffusion assay. Extracts of P. amarus, A. sativum, A. annua and C. limon were significantly (P<0.05 more sensitive to A. hydrophila and P. flourescens than M. oleifera, A. cepa and A. indica which were effective against P. flourescens. Minimum inhibitory concentrations (MIC of the extracts were 25mg/ml for P. amarus and A. annua; 25 and 100mg/ml for C. lemon and A. cepa respectively and 50mg/ml for A. indica.  Alkaloid was demonstrated in all plants except A. annua by qualitative methods. Moderate amount (++ of cardiac glycosides was demonstrated in A. sativum, M. oleifera and P. amarus. Saponin (+++ was present in M. oleifera and A. indica while, tannin (++ was present in M. oleifera, P. amarus and A. indica respectively. Phlobatanins and Anthraquinones (++ were present in P. amarus and M. oleifera respectively.  Extracts of aforementioned plants have potentials as therapy against Aeromonas hydrophila and Pseudomonas flourescens of farmed catfish.

EIR, KfK joint heat transfer experiment on a single rod, roughened with trapezoidal rounded ribs and cooled by various gases

International Nuclear Information System (INIS)

Hudina, M.; Huggenberger, M.; Dalle Donne, M.; Meyer, L.; Rehme, K.

1978-10-01

Heat transfer and pressure drop experiments with an identical fuel rod simulator have been performed at the two Research Establishments in Wuerenlingen and in Karlsruhe. The rod was artificially roughened with 'two-dimensional' ribs of trapezoidal shape and with rounded edges. The experiments at EIR were performed with CO 2 and the rough rod was contained in a smooth tube and centered by special spacers. The experiments at KfK were performed using helium and nitrogen in the same test section (rod and outer smooth tube with spacers) and air with the rod mounted in another outer smooth tube and with spacers located farther away from the measuring positions. The global measured friction factors and Stanton numbers for different gases agree reasonably well. The differences between the roughness parameters R and G are larger. The possible reasons for the uncertainties in the reduction of these parameters are discussed. It is recommended to perform further experiments with helium in a test section with spacers far apart, to investigate the effect of the temperature ratio on heat transfer and to check if the unfavourable data obtained by the experiment with air are too pessimistic for GCFR application. (orig.) [de

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.

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.

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

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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.

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

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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

Ciprofloxacin interactions with imipenem and amikacin against multiresistant Pseudomonas aeruginosa.

OpenAIRE

Giamarellou, H; Petrikkos, G

1987-01-01

In vitro interactions of ciprofloxacin with imipenem and amikacin were evaluated by the killing-curve technique against 26 Pseudomonas aeruginosa strains resistant to amikacin and resistant or moderately susceptible to ciprofloxacin and imipenem. Imipenem enhanced killing by ciprofloxacin in tests with 11 strains, whereas amikacin enhanced killing in tests with only 4 strains.

Draft Genome Sequences of Four Hospital-Associated Pseudomonas putida Isolates.

Science.gov (United States)

Mustapha, Mustapha M; Marsh, Jane W; Ezeonwuka, Chinelo D; Pasculle, Anthony W; Pacey, Marissa P; Querry, Ashley M; Muto, Carlene A; Harrison, Lee H

2016-09-29

We present here the draft genome sequences of four Pseudomonas putida isolates belonging to a single clone suspected for nosocomial transmission between patients and a bronchoscope in a tertiary hospital. The four genome sequences belong to a single lineage but contain differences in their mobile genetic elements. Copyright © 2016 Mustapha et al.

Draft genome sequence of Pseudomonas sp. strain M47T1, carried by Bursaphelenchus xylophilus isolated from Pinus pinaster.

Science.gov (United States)

Proença, Diogo Neves; Espírito Santo, Christophe; Grass, Gregor; Morais, Paula V

2012-09-01

The draft genome sequence of Pseudomonas sp. strain M47T1, carried by the Bursaphelenchus xylophilus pinewood nematode, the causative agent of pine wilt disease, is presented. In Pseudomonas sp. strain M47T1, genes that make this a plant growth-promoting bacterium, as well as genes potentially involved in nematotoxicity, were identified.

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

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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.

Polysaccharides serve as scaffold of biofilms formed by mucoid Pseudomonas aeruginosa

DEFF Research Database (Denmark)

Yang, Liang; Hengzhuang, Wang; Wu, Hong

2012-01-01

Chronic lung infection by mucoid Pseudomonas aeruginosa is one of the major pathologic features in patients with cystic fibrosis. Mucoid P. aeruginosa is notorious for its biofilm forming capability and resistance to immune attacks. In this study, the roles of extracellular polymeric substances f...

Complete Genome Sequence of Pseudomonas aeruginosa Phage AAT-1.

Science.gov (United States)

Andrade-Domínguez, Andrés; Kolter, Roberto

2016-08-25

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

A Phytoanticipin Derivative, Sodium Houttuyfonate, Induces in Vitro Synergistic Effects with Levofloxacin against Biofilm Formation by Pseudomonas aeruginosa

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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.

Detection of bla-IMP-1 and bla-IMP-2 Genes Among Metallo-β-lactamase-Producing Pseudomonas Aeruginosa Isolated from Burn Patients in Isfahan

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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.

Mass Spectrometric Characterization of Oligomers in Pseudomonas aeruginosa Azurin Solutions

Czech Academy of Sciences Publication Activity Database

Sokolová, L.; Williamson, H.; Sýkora, Jan; Hof, Martin; Gray, H. B.; Brutschy, B.; Vlček, Antonín

2011-01-01

Roč. 115, č. 16 (2011), s. 4790-4800 ISSN 1520-6106 R&D Projects: GA MŠk(CZ) ME10124; GA MŠk(CZ) LC06063 Institutional research plan: CEZ:AV0Z40400503 Keywords : mass spectrometry * oligomers * pseudomonas aeruginosa azurin solutions Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 3.696, year: 2011

Metabolism of amino acid amides in Pseudomonas putida ATCC 12633

NARCIS (Netherlands)

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

1993-01-01

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

Study on Antibiotic compounds from Pseudomonas aeruginosa NO4 Strain

Energy Technology Data Exchange (ETDEWEB)

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

2011-05-15

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

Pseudomonas aeruginosa. Vacunas: un reto a la investigación

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Sara C. Esnard

2004-04-01

Full Text Available Pseudomonas aeruginosa, patógeno gramnegativo versátil y oportunista debido a su gran adaptabilidad fisiológica, potencial metabólico y mecanismos de virulencia, es causa frecuente a escala mundial de severas o letales infecciones en pacientes hospitalizados. El empeño por lograr terapias alternativas para prevenir o combatir las infecciones producidas por P. aeruginosa ha ocupado a investigadores de todo el mundo desde la segunda mitad del pasado siglo y actualmente se continúan reportando trabajos que respaldan los ensayos de candidatos vacunales, fundamentalmente a partir de antígenos proteicos, mayoritariamente basados en la construcción de vacunas recombinantes. En este artículo se presenta una revisión de trabajos publicados sobre las investigaciones desarrolladas en diferentes países, con el objetivo de obtener candidatos vacunales para la prevención o tratamiento de las infecciones causadas por Pseudomonas aeruginosa, a partir de la década de los años 50 del siglo XX hasta el 2003.

PARTIAL PURIFICATION AND CHARACTERIZATION OF ALKALOPHILIC PROTEASE FROM PSEUDOMONAS AERUGINOSA

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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.

Study on Antibiotic compounds from Pseudomonas aeruginosa NO4 Strain

International Nuclear Information System (INIS)

Nam, Ji Young; Kim, Jin Kyu

2011-01-01

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

Variable Copy Number, Intra-Genomic Heterogeneities and Lateral Transfers of the 16S rRNA Gene in Pseudomonas

Science.gov (United States)

Bodilis, Josselin; Nsigue-Meilo, Sandrine; Besaury, Ludovic; Quillet, Laurent

2012-01-01

Even though the 16S rRNA gene is the most commonly used taxonomic marker in microbial ecology, its poor resolution is still not fully understood at the intra-genus level. In this work, the number of rRNA gene operons, intra-genomic heterogeneities and lateral transfers were investigated at a fine-scale resolution, throughout the Pseudomonas genus. In addition to nineteen sequenced Pseudomonas strains, we determined the 16S rRNA copy number in four other Pseudomonas strains by Southern hybridization and Pulsed-Field Gel Electrophoresis, and studied the intra-genomic heterogeneities by Denaturing Gradient Gel Electrophoresis and sequencing. Although the variable copy number (from four to seven) seems to be correlated with the evolutionary distance, some close strains in the P. fluorescens lineage showed a different number of 16S rRNA genes, whereas all the strains in the P. aeruginosa lineage displayed the same number of genes (four copies). Further study of the intra-genomic heterogeneities revealed that most of the Pseudomonas strains (15 out of 19 strains) had at least two different 16S rRNA alleles. A great difference (5 or 19 nucleotides, essentially grouped near the V1 hypervariable region) was observed only in two sequenced strains. In one of our strains studied (MFY30 strain), we found a difference of 12 nucleotides (grouped in the V3 hypervariable region) between copies of the 16S rRNA gene. Finally, occurrence of partial lateral transfers of the 16S rRNA gene was further investigated in 1803 full-length sequences of Pseudomonas available in the databases. Remarkably, we found that the two most variable regions (the V1 and V3 hypervariable regions) had probably been laterally transferred from another evolutionary distant Pseudomonas strain for at least 48.3 and 41.6% of the 16S rRNA sequences, respectively. In conclusion, we strongly recommend removing these regions of the 16S rRNA gene during the intra-genus diversity studies. PMID:22545126

Antimicrobial resistance in Pseudomonas sp. causing infections in trauma patients: A 6 year experience from a south asian country

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Nonika Rajkumari

2014-01-01

Full Text Available Drug resistance to Pseudomonas sp. has spread to such a level irrespective of the type of patients, that its pattern of distribution and antibiotic resistance needs to be studied in detail, especially in trauma patients and hence the study. A 6 year study was carried out among trauma patients to see the trend and type of resistance prevalent in the apex hospital for trauma care in India among nonduplicate isolates where multidrug-resistance (MDR, cross-resistance and pan-drug resistance in Pseudomonas sp. were analyzed. Of the total 2,269 isolates obtained, the species, which was maximally isolated was Pseudomonas aeruginosa (2,224, 98%. The highest level of resistance was seen in tetracycline (2,166, 95.5%, P < 0.001 and chloramphenicol (2,160, 95.2%, P < 0.001 and least in meropenem (1,739, 76.7%, P < 0.003. Of the total, 1,692 (74.6% isolates were MDR in which P. aeruginosa (75% were maximum. MDR Pseudomonas is slowing increasing since the beginning of the study period. Of 1,797 imipenem-resistant P. aeruginosa isolated during the study period, 1,763 (98% showed resistance to ciprofloxacin or levofloxacin, suggesting that cross-resistance may have developed for imipenem due to prior use of fluoroquinolones. Antibiotic resistance in Pseudomonas sp. is fast becoming a problem in trauma patients, especially in those who requires prolong hospital stay, which calls for proper antimicrobial stewardship.

A Facile and Efficient Synthesis of Diaryl Amines or Ethers under Microwave Irradiation at Presence of KF/Al2O3 without Solvent and Their Anti-Fungal Biological Activities against Six Phytopathogens

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Tao Zhang

2013-09-01

Full Text Available A series of diaryl amines, ethers and thioethers were synthesized under microwave irradiation efficiently at presence of KF/Al2O3 in 83%–96% yields without any solvent. The salient characters of this method lie in short reaction time, high yields, general applicability to substrates and simple workup procedure. At the same time, their antifungal biological activities against six phytopathogen were evaluated. Most of the compounds (3b, 3c, 3g–o are more potent than thiophannate-methyl against to Magnaporthe oryzae. This implies that diaryl amine or ether moiety may be helpful in finding a fungicide against Magnaporthe oryzae.

Comparative genomic analysis of two-component regulatory proteins in Pseudomonas syringae

DEFF Research Database (Denmark)

Lavin, J.L.; Kiil, Kristoffer; Resano, O.

2007-01-01

Background: Pseudomonas syringae is a widespread bacterial plant pathogen, and strains of P. syringae may be assigned to different pathovars based on host specificity among different plant species. The genomes of P. syringae pv. syringae (Psy) B728a, pv. tomato (Pto) DC3000 and pv. phaseolicola...

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

Pseudomona pseudomallei community acquired pneumonia

International Nuclear Information System (INIS)

Severiche, Diego

1998-01-01

This is the first published case report en Colombia about pseudomona pseudomallei community acquired pneumonia. This uncommon pathogen is from the epidemiological standpoint a very important one and medical community should be aware to look after it in those patients where no other etiological pathogen is recovered. A brief summary about epidemiology is showed, emphasizing those regions where it can be found. Likewise, comments about the differential diagnosis are important since it should be considered in those patients where tuberculosis is suspected. This is particularly representative for countries with high tuberculosis rates. Furthermore, a microbiological review is shown, emphasizing on isolation techniques, descriptions about therapeutics and other regarding treatment issues according international standards. Finally; a description about the clinical picture, laboratory findings, treatment and evolution of the case reported are shown for discussion

Isolation of Pseudomonas cepacia in cystic fibrosis patient

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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.

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.

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...

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

Optimization of Pseudomonas putida KT2440 as host for the production of cis, cis-muconate from benzoate

OpenAIRE

Duuren, van, J.B.J.H.

2011-01-01

Optimization of Pseudomonas putida KT2440 as host for the production of cis, cis-muconate from benzoate P. putida KT2440 was used as biocatalyst given its versatile and energetically robust metabolism. Therefore, a mutant was generated and a process developed based on which a life cycle assessment (LCA) was performed. Additionally, the growth related parameters were experimentally obtained to constrain the metabolic model iJP815 further. The mutant Pseudomonas putida KT2440-JD1 was deri...

The influence of the marine aerobic Pseudomonas strain on the corrosion of 70/30 Cu-Ni alloy

International Nuclear Information System (INIS)

Yuan, S.J.; Choong, Amy M.F.; Pehkonen, S.O.

2007-01-01

A comparative study of the corrosion behavior of the 70/30 Cu-Ni alloy in a nutrient-rich simulated seawater-based nutrient-rich medium in the presence and the absence of a marine aerobic Pseudomonas bacterium was carried out by electrochemical experiments, microscopic methods and X-ray photoelectron spectroscopy (XPS). The results of Tafel plot measurements showed the noticeable increase in the corrosion rate of the alloy in the presence of the Pseudomonas bacteria as compared to the corresponding control samples. The E1S data demonstrated that the charge transfer resistance, R ct , and the resistance of oxide film, R f , gradually increased with time in the abiotic medium; whereas, both of them dramatically decreased with time in the biotic medium inoculated with the Pseudomonas, indicative of the acceleration of corrosion rates of the alloy. The bacterial cells preferentially attached themselves to the alloy surface to form patchy or blotchy biofilms, as observed by fluorescent microscopy (FM). Scanning electron microscopy (SEM) images revealed the occurrence of micro-pitting corrosion underneath the biofilms on the alloy surface after the biofilm removal. XPS studies presented the evolution of the passive film on the alloy surface with time in the presence and the absence of the Pseudomonas bacteria under experimental conditions, and further revealed that the presence of the Pseudomonas cells and its extra-cellular polymers (EPS) on the alloy surface retarded the formation process or impaired the protective nature of the oxide film. Furthermore, XPS results verified the difference in the chelating functional groups between the conditioning layers and the bacterial cells and the EPS in the biofilms, which was believed to connect with the loss of the passivity of the protective oxide film

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.

Development of Topical Treatment for Pseudomonas aeruginosa Wound Infections by Quorum-Sensing Inhibitors Mediated by Poly(amidoamine) (PAMAM) Dendrimers

Science.gov (United States)

2013-01-01

dendrimers would provide added benefits as a delivery vehicle of QSI compounds to inhibit PA biofilms, by both increasing the transport of QSI as drug...Pseudomonas aeruginosa Wound Infections by Quorum-Sensing Inhibitors Mediated by Poly(amidoamine) (PAMAM) Dendrimers PRINCIPAL INVESTIGATOR...Development of Topical Treatment for Pseudomonas aeruginosa Wound Infections by Quorum-Sensing Inhibitors Mediated by Poly(amidoamine) (PAMAM) Dendrimers

Complete genome sequence of Pseudomonas rhizosphaerae IH5T (=DSM 16299T), a phosphate-solubilizing rhizobacterium for bacterial biofertilizer.

Science.gov (United States)

Kwak, Yunyoung; Jung, Byung Kwon; Shin, Jae-Ho

2015-01-10

Pseudomonas rhizosphaerae IH5(T) (=DSM 16299(T)), isolated from the rhizospheric soil of grass growing in Spain, has been reported as a novel species of the genus Pseudomonas harboring insoluble phosphorus solubilizing activity. To understanding the multifunctional biofertilizer better, we report the complete genome sequence of P. rhizosphaerae IH5(T). Copyright © 2014 Elsevier B.V. All rights reserved.

Testosterone 15β-hydroxylation by solvent tolerant Pseudomonas putida S12

NARCIS (Netherlands)

Ruijssenaars, H.J.; Sperling, E.M.G.M.; Wiegerinck, P.H.G.; Brands, F.T.L.; Wery, J.; Bont, J.A.M.de

2007-01-01

A steroid 15β-hydroxylating whole-cell solvent tolerant biocatalyst was constructed by expressing the Bacillus megaterium steroid hydroxylase CYP106A2 in the solvent tolerant Pseudomonas putida S12. Testosterone hydroxylation was improved by a factor 16 by co-expressing Fer, a putative Fe-S protein

Evaluation of biocontrol potential of epiphytic fluorescent pseudomonas as associated with healthy fruits and vegetables against root rot and root knot pathogens of mungbean

International Nuclear Information System (INIS)

Habiba, A.; Noreen, R.; Ali, S. A.; Sultana, V.; Ara, J.

2016-01-01

Endophytic and rhizospheric fluorescent Pseudomonas have widely been used as biological control agents against soilborne plant pathogens. In this study, fifteen epiphytic fluorescent Pseudomonas isolated from the surfaces of citrus (grapefruit, orange and lemon) melon and tomato fruits were characterized for their in vitro activity against root rotting fungi viz., Macrophomina phaseolina, Fusarium solani, F. oxysporum and Rhizoctonia solani and nematicidal activity against the second stage juveniles of Meloidogyne javanica. Out of fifteen Pseudomonas isolates HAB-16, HAB-1 and HAB-25 inhibited the growth of all the test fungi and showed maximum nematicidal activity against second stage juvenile of M. javanica. Based on their effective in vitro activity nine epiphytic fluorescent Pseudomonas were evaluated for their growth promoting ability and biocontrol activity in screen house on mungbean. Pseudomonas isolates (HAB-13, HAB-2, HAB-4, HAB-1, HAB-14, HAB-9, HAB-7 and HAB-25) used as soil drench greatly reduced the root rot-root knot infection and thereby enhanced plant growth, root nodulation and yield in mungbean. Besides, rhizospheric and endophytic, epiphytic fluorescent Pseudomonas associated with healthy fruits may be used as biocontrol agent against root rotting fungi, besides, using for the mangemnet of postharvest diseases. (author)

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.

Pyoverdine and PQS Mediated Subpopulation Interactions Involved in Pseudomonas aeruginosa Biofilm Formation

DEFF Research Database (Denmark)

Yang, Liang; Nilsson, Martin; Gjermansen, Morten

2009-01-01

Using flow chamber-grown Pseudomonas aeruginosa biofilms as model system, we show in the present study that formation of heterogeneous biofilms may occur through mechanisms that involve complex subpopulation interactions. One example of this phenomenon is expression of the iron...

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...

Catabolite repression and nitrogen control of allantoin-degrading enzymes in Pseudomonas aeruginosa

NARCIS (Netherlands)

Janssen, D.B.; Drift, C. van der

1983-01-01

The formation of the allantoin-degrading enzymes allantoinase, allantoicase and ureidoglycolase in Pseudomonas aeruginosa was found to be regulated by induction, catabolite repression and nitrogen control. Induction was observed when urate, allantoin or allantoate were included in the growth medium,

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

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

Establishment of oxidative D-xylose metabolism in Pseudomonas putida S12

NARCIS (Netherlands)

Meijnen, J.P.; Winde, J.H. de; Ruijssenaars, H.J.

2009-01-01

The oxidative D-xylose catabolic pathway of Caulobacter crescentus, encoded by the xylXABCD operon, was expressed in the gram-negative bacterium Pseudomonas putida S12. This engineered transformant strain was able to grow on D-xylose as a sole carbon source with a biomass yield of 53% (based on g

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-...

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

Functional study of elafin cleaved by Pseudomonas aeruginosa metalloproteinases.

LENUS (Irish Health Repository)

Guyot, Nicolas

2010-06-01

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

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

Accumulation of a Polyhydroxyalkanoate Containing Primarily 3-Hydroxydecanoate from Simple Carbohydrate Substrates by Pseudomonas sp. Strain NCIMB 40135

OpenAIRE

Haywood, Geoffrey W.; Anderson, Alistair J.; Ewing, David F.; Dawes, Edwin A.

1990-01-01

A number of Pseudomonas species have been identified which accumulate a polyhydroxyalkanoate containing mainly 3-hydroxydecanoate monomers from sodium gluconate as the sole carbon source. One of these, Pseudomonas sp. strain NCIMB 40135, was further investigated and shown to accumulate such a polyhydroxyalkanoate from a wide range of carbon sources (C2 to C6); however, when supplied with octanoic acid it produced a polyhydroxyalkanoate containing mainly 3-hydroxyoctanoate monomers. Polymer sy...

Multidrug Resistant Pseudomonas Mycotic Pseudoaneurysm following Cardiac Transplant Bridged by Ventricular Assistant Device

Directory of Open Access Journals (Sweden)

C. Aye

2017-01-01

Full Text Available Mycotic pseudoaneurysm of aorta following cardiac surgery is rare but is highly fatal if it is unrecognized and untreated. Here, we report a case of a 45-year-old male patient who presented with rapidly progressive multiple pseudoaneurysms of the ascending aorta infected with multidrug resistant (MDR Pseudomonas aeruginosa at 5 weeks after cardiac transplantation, on a background of prior bridging therapy with left ventricular assistant device (LVAD. The patient was successfully treated with the newer cephalosporin, Ceftolozane/Tazobactam, in combination with surgery. This is the first reported case of mycotic pseudoaneurysm infected with MDR Pseudomonas. This case also highlights the importance of high vigilance and timely multimodality treatment in the diagnosis and management of mycotic pseudoaneurysm following cardiac transplant, especially in patients who had LVAD.

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.

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 ...

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

Biofilm formation in surface and drinking water distribution systems in Mafikeng, South Africa

Directory of Open Access Journals (Sweden)

Suma George Mulamattathil

2014-11-01

Full Text Available Poor quality source water and poorly treated reused wastewater may result in poor quality drinking water that has a higher potential to form biofilms. A biofilm is a group of microorganisms which adhere to a surface. We investigated biofilm growth in the drinking water distribution systems in the Mafikeng area, in the North- West Province of South Africa. Analysis was conducted to determine the presence of faecal coliforms, total coliforms, Pseudomonas spp. and Aeromonas spp. in the biofilms. Biofilms were grown on a device that contained copper and galvanised steel coupons. A mini tap filter – a point-of-use treatment device which can be used at a single faucet – was also used to collect samples. Scanning electron microscopy demonstrated that multi-species biofilms developed on all the coupons as well as on the point-of-use filters. Galvanised steel and carbon filters had the highest density of biofilm. Total coliforms, faecal coliforms and Pseudomonas spp. were isolated from raw water biofilm coupons only. Aeromonas spp. and Pseudomonas spp. were isolated from filters. The susceptibility of selected isolates was tested against 11 antibiotics of clinical interest. The most prevalent antibiotic resistance phenotype observed was KF-AP-C-E-OT-K-TM-A. The presence of virulence genes was determined using the polymerase chain reaction. These results indicate that bacteria present in the water have the ability to colonise as biofilms and drinking water biofilms may be a reservoir for opportunistic bacteria including Pseudomonas and Aeromonas species.

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

Pseudomonas aeruginosa lipopolysaccharide induces CF-like alteration of protein secretion by human tracheal gland cells.

Science.gov (United States)

Kammouni, W; Figarella, C; Baeza, N; Marchand, S; Merten, M D

1997-12-18

Human tracheal gland (HTG) serous cells are now believed to play a major role in the physiopathology of cystic fibrosis. Because of the persistent inflammation and the specific infection by Pseudomonas aeruginosa in the lung, we looked for the action of the lipopolysaccharide (LPS) of this bacteria on human tracheal gland cells in culture by studying the secretion of the secretory leukocyte proteinase inhibitor (SLPI) which is a specific serous secretory marker of these cells. Treatment with Pseudomonas aeruginosa LPS resulted in a significant dose-dependent increase in the basal production of SLPI (+ 250 +/- 25%) whilst the SLPI transcript mRNA levels remained unchanged. This LPS-induced increase in secretion was inhibited by glucocorticoides. Furthermore, LPS treatment of HTG cells induces a loss of responsiveness to carbachol and isoproterenol but not to adenosine triphosphate. These findings indicate that HTG cells treated by Pseudomonas aeruginosa LPS have the same behavior as those previously observed with CF-HTG cells. Exploration by using reverse transcriptase polymerase chain reaction amplification showed that LPS downregulated cystic fibrosis transmembrane conductance regulator (CFTR) mRNA expression in HTG cells indicative of a link between CFTR function and consequent CF-like alteration in protein secretory process.

Siderophore cheating and cheating resistance shape competition for iron in soil and freshwater Pseudomonas communities.

Science.gov (United States)

Butaitė, Elena; Baumgartner, Michael; Wyder, Stefan; Kümmerli, Rolf

2017-09-04

All social organisms experience dilemmas between cooperators performing group-beneficial actions and cheats selfishly exploiting these actions. Although bacteria have become model organisms to study social dilemmas in laboratory systems, we know little about their relevance in natural communities. Here, we show that social interactions mediated by a single shareable compound necessary for growth (the iron-scavenging pyoverdine) have important consequences for competitive dynamics in soil and pond communities of Pseudomonas bacteria. We find that pyoverdine non- and low-producers co-occur in many natural communities. While non-producers have genes coding for multiple pyoverdine receptors and are able to exploit compatible heterologous pyoverdines from other community members, producers differ in the pyoverdine types they secrete, offering protection against exploitation from non-producers with incompatible receptors. Our findings indicate that there is both selection for cheating and cheating resistance, which could drive antagonistic co-evolution and diversification in natural bacterial communities.Lab strains of Pseudomonas are model systems for the evolution of cooperation over public goods (iron-scavenging siderophores). Here, Butaitė et al. add ecological and evolutionary insight into this system by showing that cheating and resistance to cheating both shape competition for iron in natural Pseudomonas communities.

Role of mungbean root nodule associated fluorescent Pseudomonas and rhizobia in suppressing the root rotting fungi and root knot nematodes in chickpea (Cicer arietinum L.)

International Nuclear Information System (INIS)

Noreen, R.; Shafique, A.; Haque, S.E.; Ali, S.A.

2016-01-01

Three isolates each of fluorescent Pseudomonas (NAFP-19, NAFP-31 and NAFP-32) and rhizobia (NFB- 103, NFB-107 and NFB-109) which were originally isolated from root nodules of mungbean (Vigna radiata) showed significant biocontrol activity in the screen house and under field condition, against root rotting fungi viz., Macrophomina phaseolina, Fusarium solani, F. oxysporum and Rhizoctonia solani evaluated on chickpea. Biocontrol potential of these isolates was also evaluated against Meloidogyne incognita, the root knot nematode. Application of Pseudomonas and rhizobial isolates as a soil drench, separately or mixed significantly reduced root rot disease under screen house and field conditions. Nematode penetration in roots was also found significantly less in rhizobia or Pseudomonas treatments used separately or mixed as compared to control. Fluorescent Pseudomonas treated plants produced greater number of nodules per plant than control plants and about equal to rhizobia treated plants, indicating that root nodule associated fluorescent Pseudomonas enhance root nodulation. (author)