Influencia de polimorfismos genéticos, variables analíticas y ambientales en las concentraciones valle de terapia anti-TNF de pacientes con enfermedad inflamatoria intestinal

OpenAIRE

Romero Cara, Patricia

2015-01-01

OBJETIVOS La terapia anti-TNF-alfa está indicada en el tratamiento de las enfermedades inflamatorias crónicas. Cuando la respuesta es inadecuada se recomienda la intensificación de la dosis. Sin embargo, ni las razones para esta recomendación, ni los múltiples mecanismos implicados son bien conocidos. Nuestro objetivo principal es investigar si polimorfismos en los genes FCGRT, FCGR2A y FCGR3A (relacionados con el metabolismo y eliminación de inmunoglobulinas) ejercen una influencia en la ...

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...

Pathogenesis could be one of the anti-cheating mechanisms for Pseudomonas aeruginosa society.

Science.gov (United States)

Huang, Zhengwei; Jiang, Yuntao; Liang, Jingping

2011-02-01

Pseudomonas aeruginosa is the major pathogen of chronic lung infections in individuals with cystic fibrosis (CF). Traditionally, it has been regarded as living in planktonic form, and as being able to perform only simple physiological activities. Recent studies in biofilm infections in CF patients, however, show that P. aeruginosa can perform many social behaviors, like cooperation and cheating. Based on the theory of "survival of the fittest", it may be presumed that every individual will take advantage of cheating instead of cooperation to increase its fitness, at the cost of group survival. In reality, however, a bacterial society can remain stable, even though cheaters arise frequently in the population. It is therefore possible that there are anti-cheating mechanisms in a bacterial society. The cheaters of P. aeruginosa will cause the loss or the decrease of the pathogenesis of the microorganism in the cystic fibrosis host. These defects in pathogenesis will be disadvantageous to bacterial colonization and compromise the resistance to host immunity. We therefore propose the hypothesis that the pathogenesis in cystic fibrosis lung infections could be one of the anti-cheating mechanisms that contribute to the hidden costs of the cheater strains. To test this hypothesis, we designed an experiment in an animal model of CF. If this hypothesis can be confirmed, it will illustrate that nontrivial analogies exist between microbial social behaviors and the social traits that are observed in the more traditional model systems for sociobiology. This will not only provide a genetic model for sociobiology research, but also cast light on the social control of chronic bacterial infections. Copyright © 2010. Published by Elsevier Ltd.

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...

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?

Efecto de suplementos de zinc en la incidencia de caries y en la concentración de Inmunoglobulinas a salivales en niños escolares de talla baja

OpenAIRE

Parra Coronel, Janeth; Astudillo, Diana; Sempértegui, Fernando; Universidad de Cuenca; Dirección de Investigación de la Universidad de Cuenca; DIUC

2013-01-01

La población de niños en el Ecuador presenta una alta prevalencia de deficiencia crónica de zinc, asociada a una deficiencia de la inmunidad celular y humoral y un incremento elevado de caries dental. Esta investigación presenta el efecto de la ingesta de 10 mg de sulfato de zinc versus el grupo control que recibe una solución con una sustancia inactiva durante 42 semanas y se observa el cambio detectado en relación al peso de los niños, la talla, la concentración de Inmunoglobulina A (IgA) e...

Stigmatellin Y - An anti-biofilm compound from Bacillus subtilis BR4 possibly interferes in PQS-PqsR mediated quorum sensing system in Pseudomonas aeruginosa.

Science.gov (United States)

Boopathi, Seenivasan; Vashisth, Rajesh; Manoharan, Prabu; Kandasamy, Ruckmani; Sivakumar, Natesan

2017-05-15

Hitherto this is the first report pertaining to production of biofilm inhibitory compound(s) (BIC) from Bacillus subtilis BR4 against Pseudomonas aeruginosa (ATCC 27853) coupled with production optimization. In order to achieve this, combinations of media components were formulated by employing statistical tools such as Plackett-Burman analysis and central composite rotatable design (CCRD). It was evident that at 35mlL -1 glycerol and 3.8gL -1 casamino acid, anti-biofilm activity and production of extracellular protein significantly increased by 1.5-fold and 1.2-fold, respectively. These results corroborate that the combination of glycerol and casamino acid plays a key role in the production of BIC. Further, metabolic profiling of BIC was carried out using liquid chromatography/tandem mass spectrometry (LC-MS/MS) based on m/z value. The presence of Stigmatellin Y was predicted with monoisotopic neutral mass of 484.2825Da. In support of optimization study, higher production of BIC was confirmed in the optimized-media-grown BR4 (OPT-BR4) than in the ideal-media-grown BR4 (ID-BR4) by LC-MS/MS analysis. PqsR in P. aeruginosa is a potential target for anti-virulent therapy. Molecular docking study has revealed that Stigmatellin Y interacts with PqsR in the similar orientation like a cognate signal (PQS) and synthetic inhibitor. In addition, Stigmatellin Y was found to exhibit interaction with four more amino acid residues of PqsR to establish strong affinity. Stigmatellin Y thus might play a role of competitor for PQS to distract PQS-PqsR mediated communication in P. aeruginosa. The present investigation thus paves new avenues to develop anti-Pseudomonas virulent therapy. Copyright © 2017 Elsevier Ltd. All rights reserved.

Immunoglobulin Fc receptors in clinical strains of Staphylococcus aureus do not confer resistance to Phagocytosis in an in vitro assay Los receptores Fc para inmunoglobulinas en cepas clínicas de Staphylococcus aureus no confieren resistencia a la fagocitosis in vitro

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Benito VEGA

1999-05-01

Full Text Available Staphylococcus aureus binds Immunoglobulin G (IgG on its external surface due to the presence of specific receptors for the Fc domain of this immunoglobulin. This mechanism represents a kind of camouflage against phagocytic cells. In order to confirm that possibility an in vitro evaluation of the phagocytic activity of leukocytes polymorpho-nuclear (PMN against strains of Staphylococcus aureus was done, comparing 18 strains isolated from clinical samples and 16 from healthy individuals. The presence of Fc receptors was evaluated by haemagglutination (HA with erythrocytes group A after incubation of the strains with IgG anti blood group A. Phagocytosis of S. aureus was carried out by mixing live bacteria with a suspension of human PMN and incubating at 37 °C for 1 h; survivors were counted as colony forming units by plating. The strains from clinical specimens showed higher HA than those from healthy individuals (p = 0.01; but the former were killed more efficiently than the latter (80-90% and 40%, respectively. It is may be possible that S. aureus showed different behavior in vivo, where could express other virulence factors to prevent the action of phagocytes.Staphylococcus aureus liga inmunoglobulinas G (IgG a su superficie externa debido a la presencia de receptores para el dominio Fc de esas inmunoglobulinas. Este mecanismo representa una clase de camuflage contra células fagocíticas. Para confirmar tal posibilidad se realizó una evaluación in vitro de la actividad fagocítica de leucocitos polimorfonucleares (PMN contra cepas de Staphylococcus aureus, comparando 18 cepas aisladas de casos clínicos y 16 de individuos sanos. La presencia de receptores fue evaluada por hemaglutinación (HA con eritrocitos grupo A luego que las cepas fueron incubadas con IgG anti grupo sanguíneo A. La fagocitosis de S. aureus fue realizada mezclando células vivas con una suspensión de PMN e incubada a 37 °C por una hora; las bacterias sobrevivientes

Preventing Pseudomonas aeruginosa and Chromobacterium violaceum infections by anti-adhesion-active components of edible seeds

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Rachmaninov Ofra

2012-02-01

Full Text Available Abstract Background Pseudomonas aeruginosa adhesion to animal/human cells for infection establishment involves adhesive proteins, including its galactose- and fucose-binding lectins PA-IL (LecA and PA-IIL (LecB. The lectin binding to the target-cell receptors may be blocked by compatible glycans that compete with those of the receptors, functioning as anti-adhesion glycodecoys. The anti-adhesion treatment is of the utmost importance for abrogating devastating antibiotic-resistant P. aeruginosa infections in immunodeficient and cystic fibrosis (CF patients. This strategy functions in nature in protecting embryos and neonates. We have shown that PA-IL, PA-IIL, and also CV-IIL (a PA-IIL homolog produced in the related pathogen Chromobacterium violaceum are highly useful for revealing natural glycodecoys that surround embryos in diverse avian eggs and are supplied to neonates in milks and royal jelly. In the present study, these lectins were used as probes to search for seed embryo-protecting glycodecoys. Methods The lectin-blocking glycodecoy activities were shown by the hemagglutination-inhibition test. Lectin-binding glycoproteins were detected by Western blotting with peroxidase-labeled lectins. Results The present work reports the finding - by using PA-IL, PA-IIL, and CV-IIL - of rich glycodecoy activities of low ( 10 kDa compounds (including glycoproteins in extracts of cashew, cocoa, coffee, pumpkin, and tomato seeds, resembling those of avian egg whites, mammal milks, and royal jelly. Conclusions Edible seed extracts possess lectin-blocking glycodecoys that might protect their embryos from infections and also might be useful for hampering human and animal infections.

The anti-cancerous drug doxorubicin decreases the c-di-GMP content in Pseudomonas aeruginosa but promotes biofilm formation

DEFF Research Database (Denmark)

Groizeleau, Julie; Rybtke, Morten; Andersen, Jens Bo

2016-01-01

Current antibiotic treatments are insufficient in eradicating bacterial biofilms, which represent the primary cause of chronic bacterial infections. Thus, there is an urgent need for new strategies to eradicate biofilm infections. The second messenger c-di-GMP is a positive regulator of biofilm...... formation in many clinically relevant bacteria. It is hypothesized that drugs lowering the intracellular level of c-di-GMP will force biofilm bacteria into a more treatable planktonic lifestyle. To identify compounds capable of lowering c-di-GMP levels in Pseudomonas aeruginosa, we screened 5000 compounds...... for their potential c-di-GMP-lowering effect using a recently developed c-di-GMP biosensor strain. Our screen identified the anti-cancerous drug doxorubicin as a potent c-di-GMP inhibitor. In addition, the drug decreased the transcription of many biofilm-related genes. However, despite its effect on the c-di-GMP...

Metabolomics-Based Screening of Biofilm-Inhibitory Compounds against Pseudomonas aeruginosa from Burdock Leaf

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Zaixiang Lou

2015-09-01

Full Text Available Screening of anti-biofilm compounds from the burdock leaf based on metabolomics is reported here. The crystal violet assay indicated 34% ethanol elution fraction of burdock leaf could completely inhibit biofilm formation of Pseudomonas aeruginosa at 1 mg·mL−1. Then, the chemical composition of burdock leaf fraction was analyzed by ultra-performance liquid chromatography-mass spectrometry (UPLC-MS and 11 active compounds (chlorogenic acid, caffeic acid, p-coumaric acid, quercetin, ursolic acid, rutin, cynarin, luteolin, crocin, benzoic acid, and Tenacissoside I were identified. Lastly, UPLC-MS analysis was employed to obtain the metabolic fingerprints of burdock leaf fractions before and after inhibiting the biofilm of Pseudomonas aeruginosa. The metabolic fingerprints were transformed to data, analyzed with PLS-DA (partial least squares discriminant analysis and the peaks whose area was significantly changed were found out. Thus, 81 compounds were screened as potential anti-biofilm ingredients. Among them, rutin, ursolic acid, caffeic acid, p-coumaric acid and quercetin were identified and confirmed as the main anti-biofilm compounds in burdock leaf. The study provided basic anti-biofilm profile data for the compounds in burdock leaf, as well as provided a convenient method for fast screening of anti-biofilm compounds from natural plants.

Anti-quorum sensing activity of Psidium guajava L. flavonoids against Chromobacterium violaceum and Pseudomonas aeruginosa PAO1.

Science.gov (United States)

Vasavi, Halkare Suryanarayana; Arun, Ananthapadmanabha Bhagwath; Rekha, Punchapady-Devasya

2014-05-01

Psidium guajava L., which has been used traditionally as a medicinal plant, was explored for anti-quorum sensing (QS) activity. The anti-QS activity of the flavonoid (FL) fraction of P. guajava leaves was determined using a biosensor bioassay with Chromobacterium violaceum CV026. Detailed investigation of the effects of the FL-fraction on QS-regulated violacein production in C. violaceum ATCC12472 and pyocyanin production, proteolytic, elastolytic activities, swarming motility and biofilm formation in Pseudomonas aeruginosa PAO1 was performed using standard methods. Possible mechanisms of QS-inhibition were studied by assessing violacein production in response to N-acyl homoserine lactone (AHL) synthesis in the presence of the FL-fraction in C. violaceum ATCC31532 and by evaluating the induction of violacein in the mutant C. violaceum CV026 by AHL extracted from the culture supernatants of C. violaceum 31532. Active compounds in the FL-fraction were identified by liquid chromatography-mass spectrometry (LC-MS). Inhibition of violacein production by the FL-fraction in a C. violaceum CV026 biosensor bioassay indicated possible anti-QS activity. The FL-fraction showed concentration-dependent decreases in violacein production in C. violaceum 12472 and inhibited pyocyanin production, proteolytic and elastolytic activities, swarming motility and biofilm formation in P. aeruginosa PAO1. Interestingly, the FL-fraction did not inhibit AHL synthesis; AHL extracted from cultures of C. violaceum 31532 grown in the presence of the FL-fraction induced violacein in the mutant C. violaceum CV026. LC-MS analysis revealed the presence of quercetin and quercetin-3-O-arabinoside in the FL-fraction. Both quercetin and quercetin-3-O-arabinoside inhibited violacein production in C. violaceum 12472, at 50 and 100 μg/mL, respectively. Results of this study provide scope for further research to exploit these active molecules as anti-QS agents. © 2014 The Societies and Wiley Publishing

Evaluation of combinations of putative anti-biofilm agents and antibiotics to eradicate biofilms of Staphylococcus aureus and Pseudomonas aeruginosa.

Science.gov (United States)

Belfield, Katherine; Bayston, Roger; Hajduk, Nadzieja; Levell, Georgia; Birchall, John P; Daniel, Matija

2017-09-01

To evaluate potential anti-biofilm agents for their ability to enhance the activity of antibiotics for local treatment of localized biofilm infections. Staphylococcus aureus and Pseudomonas aeruginosa in vitro biofilm models were developed. The putative antibiotic enhancers N-acetylcysteine, acetylsalicylic acid, sodium salicylate, recombinant human deoxyribonuclease I, dispersin B, hydrogen peroxide and Johnson's Baby Shampoo (JBS) were tested for their anti-biofilm activity alone and their ability to enhance the activity of antibiotics for 7 or 14 days, against 5 day old biofilms. The antibiotic enhancers were paired with rifampicin and clindamycin against S. aureus and gentamicin and ciprofloxacin against P. aeruginosa. Isolates from biofilms that were not eradicated were tested for antibiotic resistance. Antibiotic levels 10× MIC and 100× MIC significantly reduced biofilm, but did not consistently eradicate it. Antibiotics at 100× MIC with 10% JBS for 14 days was the only treatment to eradicate both staphylococcal and pseudomonal biofilms. Recombinant human deoxyribonuclease I significantly reduced staphylococcal biofilm. Emergence of resistance of surviving isolates was minimal and was often associated with the small colony variant phenotype. JBS enhanced the activity of antibiotics and several other promising anti-biofilm agents were identified. Antibiotics with 10% JBS eradicated biofilms produced by both organisms. Such combinations might be useful in local treatment of localized biofilm infections. © The Author 2017. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Evaluation of anti-bacterial and anti-oxidant potential of andrographolide and echiodinin isolated from callus culture of Andrographis paniculata Nees

Science.gov (United States)

Arifullah, Mohmmed; Namsa, Nima Dandu; Mandal, Manabendra; Chiruvella, Kishore Kumar; Vikrama, Paritala; Gopal, Ghanta Rama

2013-01-01

Objective To evaluate the anti-bacterial and anti-oxidant activity of andrographolide (AND) and echiodinin (ECH) of Andrographis paniculata. Methods In this study, an attempt has been made to demonstrate the anti-microbial and anti-oxidant activity of isolated AND and ECH by broth micro-dilution method and 2,2-diphenyl-2-picryl-hydrazyl (DPPH) assay, respectively. Structure elucidation was determined by electro-spray ionization-MSD, NMR (1H and 13C) and IR spectra. Results AND was effective against most of the strains tested including Mycobacterium smegmatis, showing broad spectrum of growth inhibition activity with Minimum inhibitory concentration values against Staphylococcus aureus (100 µg/mL), Streptococcus thermophilus (350 µg/mL) Bacillus subtilis (100 µg/mL), Escherichia coli (50 µg/mL), Mycobacterium smegmatis (200 µg/mL), Klebsiella pneumonia (100 µg/mL), and Pseudomonas aeruginosa (200 µg/mL). ECH showed specific anti-bacterial activity against Staphylococcus aureus, Escherichia coli, Bacillus subtilis and Pseudomonas aeruginosa at a concentration higher than 225 µg/mL. Both AND and ECH were not effective against the two yeast strains, Candida albicans and Saccharomyces cerevisiae tested in this study. Conclusion This preliminary study showed promising anti-bacterial activity and moderate free radical scavenging activity of AND and ECH, and it may provide the scientific rationale for its popular folklore medicines. PMID:23905016

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

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Eduardo Ruiz-Bustos

2011-01-01

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

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.

Expression of the recA gene of Pseudomonas aeruginosa PAO is inducible by DNA-damaging agents

International Nuclear Information System (INIS)

Miller, R.V.; Kokjohn, T.A.

1988-01-01

Western (immunoblot) analysis using Escherichia coli anti-RecA antiserum revealed that expression of the RecA protein of Pseudomonas aeruginosa PAO is induced upon exposure of the bacterium to UV irradiation or norfloxacin, a quinolone related to nalidixic acid

Baicalin inhibits biofilm formation, attenuates the quorum sensing-controlled virulence and enhances Pseudomonas aeruginosa clearance in a mouse peritoneal implant infection model.

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Jing Luo

Full Text Available The quorum sensing (QS circuit plays a role in the precise regulation of genes controlling virulence factors and biofilm formation in Pseudomonas aeruginosa. QS-controlled biofilm formation by Pseudomonas aeruginosa in clinical settings has remained controversial due to emerging drug resistance; therefore, screening diverse compounds for anti-biofilm or anti-QS activities is important. This study demonstrates the ability of sub-minimum inhibitory concentrations (sub-MICs of baicalin, an active natural compound extracted from the traditional Chinese medicinal Scutellaria baicalensis, to inhibit the formation of Pseudomonas aeruginosa biofilms and enhance the bactericidal effects of various conventional antibiotics in vitro. In addition, baicalin exerted dose-dependent inhibitory effects on virulence phenotypes (LasA protease, LasB elastase, pyocyanin, rhamnolipid, motilities and exotoxin A regulated by QS in Pseudomonas aeruginosa. Moreover, the expression levels of QS-regulatory genes, including lasI, lasR, rhlI, rhlR, pqsR and pqsA, were repressed after sub-MIC baicalin treatment, resulting in significant decreases in the QS signaling molecules 3-oxo-C12-HSL and C4-HSL, confirming the ability of baicalin-mediated QS inhibition to alter gene and protein expression. In vivo experiments indicated that baicalin treatment reduces Pseudomonas aeruginosa pathogenicity in Caenorhabditis elegans. Greater worm survival in the baicalin-treated group manifested as an increase in the LT50 from 24 to 96 h. In a mouse peritoneal implant infection model, baicalin treatment enhanced the clearance of Pseudomonas aeruginosa from the implants of mice infected with Pseudomonas aeruginosa compared with the control group. Moreover, the combination of baicalin and antibiotics significantly reduced the numbers of colony-forming units in the implants to a significantly greater degree than antibiotic treatment alone. Pathological and histological analyses revealed

Inactivacion de virus ADN envueltos en la producción de hemoderivados (Albúmina e Inmunoglobulinas

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Ignacio Juan Ruibal Brunet

1999-08-01

Full Text Available Se estudió la inactivación del virus herpes simple humano tipo 1 como modelo de virus ADN envueltos, durante las etapas de producción de las inmunoglobulinas intramuscular e intravenosa y la albúmina humana, las etapas del método de fraccionamiento alcohólico para la obtención de estos productos, así como los métodos de remoción y/o inactivación introducidos en el proceso de manufactura, pasteurización y cromatografía de intercambio iónico. El virus se cuantificó por efecto citopático. La obtención de valores de reducción acumulativos reportados en este trabajo demuestran que el método de fraccionamiento alcohólico utilizado en Cuba como variante del método de Cohn-Oncley, combinando métodos de inactivación/remoción, produce un nivel de inactivación de virus ADN envueltos que garantiza una alta seguridad biológica de estos productos para su uso en humanos.Inactivation of human herpes simplex virus I asa model of enveloped DNA virus was studied in the stages of production of intramuscular/ intravenous inmunoglobulins and human albumin, in the phases of alcohol fractionation for obtaining these products, and in the methods of removal and/or inactivation implemented in manufacture, pasteurization and ion - exchange chromatography. The virus was quantified by cytophatic effects. The cumulative reduction values reported in this paper proved that the use of alcohol fractionation in Cuba, as a variant of Cohn - Oncley method, combined with removal/inactivation procedures resulted in enveloped DNA virus inactivation assuring high biological safety for albumin and immunoglobulins for their use in human beings.

The anti-Pseudomonas aeruginosa antibody Panobacumab is efficacious on acute pneumonia in neutropenic mice and has additive effects with meropenem.

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Thomas Secher

Full Text Available Pseudomonas aeruginosa (P. aeruginosa infections are associated with considerable morbidity and mortality in immunocompromised patients due to antibiotic resistance. Therefore, we investigated the efficacy of the anti-P. aeruginosa serotype O11 lipopolysaccharide monoclonal antibody Panobacumab in a clinically relevant murine model of neutropenia induced by cyclophosphamide and in combination with meropenem in susceptible and meropenem resistant P. aeruginosa induced pneumonia. We observed that P. aeruginosa induced pneumonia was dramatically increased in neutropenic mice compared to immunocompetent mice. First, Panobacumab significantly reduced lung inflammation and enhanced bacterial clearance from the lung of neutropenic host. Secondly, combination of Panobacumab and meropenem had an additive effect. Third, Panobacumab retained activity on a meropenem resistant P. aeruginosa strain. In conclusion, the present data established that Panobacumab contributes to the clearance of P. aeruginosa in neutropenic hosts as well as in combination with antibiotics in immunocompetent hosts. This suggests beneficial effects of co-treatment even in immunocompromised individuals, suffering most of the morbidity and mortality of P. aeruginosa infections.

Serodiagnóstico de giardiosis: identificación de inmunoglobulina G anti-Giardia duodenalis en suero mediante ELISA

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Sofía Duque

2001-09-01

Full Text Available El diagnóstico de la infección por Giardia duodenalis se basa en la identificación de quistes o trofozoítos en materia fecal, alcanzando una sensibilidad máxima de 85% en muestras seriadas, debido a la excreción intermitente de quistes. Aunque la determinación de anticuerpos no permite diferenciar entre una infección pasada y una reciente, si podría ayudar en el diagnóstico diferencial. El presente estudio tuvo como objetivos estandarizar y evaluar una prueba inmunoenzimática (ELISA para la detección de anticuerpos tipo IgG anti-Giardia duodenalis en sueros de pacientes con la infección. La preparación del antigeno se hizo a partir de trofozoitos cultivados que, inicialmente, fueron obtenidos del intestino de gerbils (Meriones unguiculatus infectados experimentalmente con quistes purificados a partir de muestras positivas de materia fecal humana. Para la estandarización y evaluación de la prueba, se emplearon 60 sueros de pacientes con giardiosis comprobada parasitológicamente (muestras positivas y 47 sueros de cordón umbilical recién cortado (muestras negativas. Como conjugado, se utilizó anti-lgG humana ligada a fosfatasa alcalina. La concentración óptima de antígeno de trofozoíto de G. duodenalis fue de 15 ug/ml y las diluciones óptimas de suero y conjugado fueron 1:25 y 1:400, respectivamente. El valor del punto de corte (absorbancia fue 0,300. Los parámetros de la prueba fueron: sensibilidad, 98,3% (intervalo de confianza de 95% (lC 95%: 89,9%-99,974; especificidad, 957% (IC 95%:84,3%-99,3%; valor predictivo positivo, 96,7% (IC 95%: 87,6%-99,4%, y valor predictivo negativo, 97,8% (IC 95%: 87,0%-99,9%. La prueba ELlSA descrita contribuirá a mejorar el diagnóstico de giardiosis y podrá ser empleada para estudios epidemiológicos de seroprevalencia.

The periplasmic protein TolB as a potential drug target in Pseudomonas aeruginosa.

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Alessandra Lo Sciuto

Full Text Available The Gram-negative bacterium Pseudomonas aeruginosa is one of the most dreaded pathogens in the hospital setting, and represents a prototype of multi-drug resistant "superbug" for which effective therapeutic options are very limited. The identification and characterization of new cellular functions that are essential for P. aeruginosa viability and/or virulence could drive the development of anti-Pseudomonas compounds with novel mechanisms of action. In this study we investigated whether TolB, the periplasmic component of the Tol-Pal trans-envelope protein complex of Gram-negative bacteria, represents a potential drug target in P. aeruginosa. By combining conditional mutagenesis with the analysis of specific pathogenicity-related phenotypes, we demonstrated that TolB is essential for P. aeruginosa growth, both in laboratory and clinical strains, and that TolB-depleted P. aeruginosa cells are strongly defective in cell-envelope integrity, resistance to human serum and several antibiotics, as well as in the ability to cause infection and persist in an insect model of P. aeruginosa infection. The essentiality of TolB for P. aeruginosa growth, resistance and pathogenicity highlights the potential of TolB as a novel molecular target for anti-P. aeruginosa drug discovery.

In vitro anti-pseudomonal potential of Juglans regia and Otostegia limbata leaves extract against planktonic and biofilm form of Pseudomonas aeruginosa

International Nuclear Information System (INIS)

Khan, I.; Khan, K.; Nawaz, M.A.; Khan, U.

2018-01-01

In the present study the anti-pseudomonal potential of crude methanolic extracts, hexane, ethyl acetate and water fractions of the leaves of Juglans regia L. and Otostegia limbata (Benth.) Boiss.against planktonic and biofilm form of clinical strains (P1, P2 and P3 strains) of Pseudomonas aeruginosa (P. aeruginosa) were evaluated. Agar well diffusion and minimum inhibitory concentration (MIC) assays were used against planktonic, whereas pellicle inhibition and static biofilm inhibition assays were performed against biofilm form of P. aeruginosa. In well diffusion assay, the crude methanolic extract of J. regia showed good bacterial inhibition than O. limbata. The J. regiacrude methanol extract had significant (+; complete breakage of pellicle layer), good (++; partial breakage of pellicle layer) and moderate (+++; uniformthin layer of pellicle formation) pellicle inhibition activity, while O. limbata had moderate (+++; uniformthin layer of pellicle formation) to weak (++++; loose thick layer pellicle formation) pellicle inhibition effect. In MIC assays, hexane and water fractions of J. regia had high (86 vs. 77%) antibacterial activity, while crude methanolic extract of O. limbata showed 51% inhibition against the most resistant P3 strain at 1000 mu g/ml concentration. In static antibiofilm assay, hexane fraction of J. regia had high (63%) inhibition compared to crude methanolic extract of O. limbata(31%) against P3 strain. The present study highlights that J. regia extracts possesses high anti-pseudomonal properties as compared to O. limbata. (author)

Anti-Pseudomonas aeruginosa IgY antibodies promote bacterial opsonization and augment the phagocytic activity of polymorphonuclear neutrophils

DEFF Research Database (Denmark)

Thomsen, Kim; Christophersen, Lars; Jensen, Peter Østrup

2016-01-01

Moderation of polymorphonuclear neutrophils (PMNs) as part of a critical defense against invading pathogens may offer a promising therapeutic approach to supplement the antibiotic eradication of Pseudomonas aeruginosa infection in non-chronically infected cystic fibrosis (CF) patients. We have...... observed that egg yolk antibodies (IgY) harvested from White leghorn chickens that target P. aeruginosa opsonize the pathogen and enhance the PMN-mediated respiratory burst and subsequent bacterial killing in vitro. The effects on PMN phagocytic activity were observed in different Pseudomonas aeruginosa...

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....

ANTI-MICROBIAL AND ANTI-AMOEBIC ACTIVITY SOME AZOMETHINES - POTENTIAL TEXTILE DYESTUFFS

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DJORDJEVIC Dragan

2016-05-01

Full Text Available In this paper, new synthesized three azomethine derivatives applied in dyeing textiles checking the anti-microbial properties of active components, at the same time [1-3]. The emphasis is thrown on the verification of anti-microbial properties that are important for obtaining textile with significantly improved performance. All compounds were characterized and evaluated for their anti-microbial activity against 7 pathogenic bacteria, 1 parasitic protozoan and 1 fungus. It estimated anti-bacterial activity in vitro against the following microorganisms Staphylococcus aureus, Bacillus anthracis, Streptococcus faecalis, Enterobacter sp., Escherichia coli, Pseudomonas aeruginosa, Proteus mirabilis, and Candida albicans. The anti-amoebic activity in vitro was evaluated against the HM1: IMSS strain of Entamoeba histolytica and the results were compared with the standard drug, metronidazole. The synthesized azomethines, showed very good substantivity for wool fibers, gave fine coloring, with good degree of exhaustion after dyeing. The combination of extended synthetic analogues of natural molecules leads to discovery of chemical entities which might be excellent anti-microbial and anti-amoebic compounds as depicted in our results. Being highly the effects this compound can be explored in future as an option for decreasing pathogenic potential of infecting from different sources. Azomethines containing hydrazone (dyestuff 1 and phenylhydrazone (dyestuff 2 as moiety show average yield and moderate inhibition activity while azomethines containing thiosemicarbazone (dyestuff 3 as moiety show higher yield and greater inhibition activity towards gram-negative and gram-positive bacteria as well as a fungus.

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).

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].

Study on screening of anti-predator rhizosphere bacterium against Caenorhabditis elegans and its anti predation mechanism

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HE Qingling

2016-08-01

Full Text Available Althoughmicrobial fertilizer is multi-effect,environmental friendly and long-term efficient,its practical application effect is but decreased for being prey by the other creators living in soil frequently.Many bacterium have developed their mechanisms that expel or kill worms to defend themselves from predators.Screening of anti-predator rhizosphere bacterium helps us to find out competitive plant growth promoting rhizobacteria(PGPR.Using Caenorhabditis elegans as sample,this study roughly observed two strains of biocontrol:Pseudomonas aurantiaca JD37 and Pseudomonas fluorescens P13.Using Escherichia coli OP50 as control group,we find the preference order of worms,from highest to lowest,is P13,OP50 and JD37.In slow killing assay,the death rate of worms for JD37 and P13 are 26.12% and 18.66% respectively.The activity and reproduction rate of C.elegans decrease when it is fed on JD37.The results of chemical and micro-biological study show that JD37 cannot produce any currently studied second metabolites which kill worms,while P13 can produce Hydrogen cyanide (HCN.All these results show that JD37 has the ability of anti-predator,and is more competitive under predation pressure,which suggests its broad application prospect as microbial fertilizer.

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

Pseudomonas syringae enhances herbivory by suppressing the reactive oxygen burst in Arabidopsis.

Science.gov (United States)

Groen, Simon C; Humphrey, Parris T; Chevasco, Daniela; Ausubel, Frederick M; Pierce, Naomi E; Whiteman, Noah K

2016-01-01

Plant-herbivore interactions have evolved in the presence of plant-colonizing microbes. These microbes can have important third-party effects on herbivore ecology, as exemplified by drosophilid flies that evolved from ancestors feeding on plant-associated microbes. Leaf-mining flies in the genus Scaptomyza, which is nested within the paraphyletic genus Drosophila, show strong associations with bacteria in the genus Pseudomonas, including Pseudomonas syringae. Adult females are capable of vectoring these bacteria between plants and larvae show a preference for feeding on P. syringae-infected leaves. Here we show that Scaptomyza flava larvae can also vector P. syringae to and from feeding sites, and that they not only feed more, but also develop faster on plants previously infected with P. syringae. Our genetic and physiological data show that P. syringae enhances S. flava feeding on infected plants at least in part by suppressing anti-herbivore defenses mediated by reactive oxygen species. Copyright © 2015 Elsevier Ltd. All rights reserved.

Anti-biofilm activity of biogenic selenium nanoparticles and selenium dioxide against clinical isolates of Staphylococcus aureus, Pseudomonas aeruginosa, and Proteus mirabilis.

Science.gov (United States)

Shakibaie, Mojtaba; Forootanfar, Hamid; Golkari, Yaser; Mohammadi-Khorsand, Tayebe; Shakibaie, Mohammad Reza

2015-01-01

The aim of the present study was to investigate the anti-biofilm activity of biologically synthesized selenium nanoparticles (Se NPs) against the biofilm produced by clinically isolated bacterial strains compared to that of selenium dioxide. Thirty strains of Staphylococcus aureus, Pseudomonas aeruginosa, and Proteus mirabilis were isolated from various specimens of the patients hospitalized in different hospitals (Kerman, Iran). Quantification of the biofilm using microtiter plate assay method introduced 30% of S. aureus, 13% of P. aeruginosa and 17% of P. mirabilis isolates as severely adherent strains. Transmission electron micrograph (TEM) of the purified Se NPs (produced by Bacillus sp. MSh-1) showed individual and spherical nano-structure in the size range of 80-220nm. Obtained results of the biofilm formation revealed that selenium nanoparticles inhibited the biofilm of S. aureus, P. aeruginosa, and P. mirabilis by 42%, 34.3%, and 53.4%, respectively, compared to that of the non-treated samples. Effect of temperature and pH on the biofilm formation in the presence of Se NPs and SeO2 was also evaluated. Copyright © 2014 Elsevier GmbH. All rights reserved.

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.

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...

Anti-Pseudomonas aeruginosa activity of hemlock (Conium maculatum, Apiaceae) essential oil.

Science.gov (United States)

Di Napoli, Michela; Varcamonti, Mario; Basile, Adriana; Bruno, Maurizio; Maggi, Filippo; Zanfardino, Anna

2018-05-21

Conium maculatum is a nitrophilous weed belonging to the Apiaceae family and occurring in hedgerows, pastures, waste ground, along rivers and roadsides. Little is known on the chemistry and bioactivity of other secondary metabolites occurring in the plant. In the present work, we have analysed the chemical composition and antimicrobial activity of the essential oils hydrodistilled from leaves and inflorescenes of C. maculatum growing in Sicily, Italy. The composition of essential oils was achieved by gas chromatography-mass spectrometry (GC-MS) analysis, whereas the inhibitory effects on the growth of two Gram negative strains, namely Escherichia coli and Pseudomonas aeruginosa were assessed by two different analysis. The essential oils exhibited different chemical profiles (1-butylpiperidine and myrcene in the inflorescenes), (mostly (E)-caryophyllene in the leaves). The latter oil was particularly active in inhibiting the growth of P. aeruginosa. These results shed light on the possible application of hemlock essential oils as antimicrobial agents.

Obtención, purificación y caracterización de anticuerpos policlonales IgY desarrollados en gallina, dirigidos contra aislamientos colombianos de Giardia duodenalis.

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Dabeiba Adriana García

2005-12-01

Full Text Available Introducción. El desarrollo de anticuerpos policlonales requiere de animales de laboratorio, generalmente, el conejo, que deben sangrarse para su obtención. Como alternativa, se han utilizado las gallinas. Objetivo. Desarrollar anticuerpos policlonales IgY anti-Giardia duodenalis y evaluar diferentes métodos para su purificación a partir de yema de huevo. Materiales y métodos. Se inmunizaron tres gallinas intramuscularmente con trofozoítos del parásito: las inmunizaciones se realizaron a los 0, 15, 30, 45, 60, 90 y 120 días. Se recolectaron huevos en cada etapa de la inmunización y se purificó la IgY por deslipidación (D y precipitación (P mediante cinco protocolos diferentes: M1: (P: sulfato de amonio/D: dextrán sulfato-cloruro de calcio, M2: (D: dextrán sulfato-cloruro de calcio/P: sulfato de amonio, M3: (D: cloroformo/ P: sulfato de amonio 50%, M4: (D: solución A/P:solución B y M5: (D: cloroformo/P: sulfato de amonio 30%. Se realizó evaluación inmunoquímica de la IgY anti-Giardia duodenalis mediante inmunodifusión, contrainmunoelectroforesis e inmunoelectrotransferencia (Western blot; la pureza de IgY por SDS-PAGE en presencia y ausencia de reductor y la concentración de la inmunoglobulina (mg/mL por espectrofotometría y densitometría. Resultados. La IgY anti-G. duodenalis mediante evaluación inmunoquímica presentó títulos hasta de 1:32. La inmunoglobulina en ausencia de reductor mostró una banda de 180 kd y en su presencia bandas de 30 y 68 kd, características de sus cadenas liviana y pesada, respectivamente. Las mayores concentraciones de inmunoglobulina se recuperaron con el método dos (M2, 4,6 mg de IgY por mL de yema de partida. Conclusiones. Por su facilidad y economía de producción en gallinas, los anticuerpos policlonales IgY anti-Giardia así obtenidos podrán utilizarse para desarrollar inmunoensayos que detecten el parásito en eluídos de heces.

"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 ...

Silver nanoparticles impede the biofilm formation by Pseudomonas aeruginosa and Staphylococcus epidermidis.

Science.gov (United States)

Kalishwaralal, Kalimuthu; BarathManiKanth, Selvaraj; Pandian, Sureshbabu Ram Kumar; Deepak, Venkataraman; Gurunathan, Sangiliyandi

2010-09-01

Biofilms are ensued due to bacteria that attach to surfaces and aggregate in a hydrated polymeric matrix. Formation of these sessile communities and their inherent resistance to anti-microbial agents are the source of many relentless and chronic bacterial infections. Such biofilms are responsible play a major role in development of ocular related infectious diseases in human namely microbial keratitis. Different approaches have been used for preventing biofilm related infections in health care settings. Many of these methods have their own demerits that include chemical based complications; emergent antibiotic resistant strains, etc. silver nanoparticles are renowned for their influential anti-microbial activity. Hence the present study over the biologically synthesized silver nanoparticles, exhibited a potential anti-biofilm activity that was tested in vitro on biofilms formed by Pseudomonas aeruginosa and Staphylococcus epidermidis during 24-h treatment. Treating these organisms with silver nanoparticles resulted in more than 95% inhibition in biofilm formation. The inhibition was known to be invariable of the species tested. As a result this study demonstrates the futuristic application of silver nanoparticles in treating microbial keratitis based on its potential anti-biofilm activity. Copyright 2010 Elsevier B.V. All rights reserved.

Early aggressive eradication therapy for intermittent Pseudomonas aeruginosa airway colonization in cystic fibrosis patients: 15 years experience

DEFF Research Database (Denmark)

Hansen, C.R.; Pressler, T.; Høiby, Niels

2008-01-01

BACKGROUND: Since 1989, CF-patients intermittently colonized with Pseudomonas aeruginosa have been treated with inhaled colistin and oral ciprofloxacin in the Copenhagen CF-centre. The study evaluates 15 years results of this treatment. METHODS: All isolates of P. aeruginosa from CF-patients inte......BACKGROUND: Since 1989, CF-patients intermittently colonized with Pseudomonas aeruginosa have been treated with inhaled colistin and oral ciprofloxacin in the Copenhagen CF-centre. The study evaluates 15 years results of this treatment. METHODS: All isolates of P. aeruginosa from CF......-patients intermittently colonized with P. aeruginosa from 1989 to 2003 were identified All anti-P. aeruginosa treatments were evaluated for antibiotics used, treatment duration, pseudomonas-free interval and development of chronic infection. All P. aeruginosa isolates were assessed for resistance and for non......-mucoid or mucoid phenotype. RESULTS: 146 CF-patients were included in the study (1106 patient-years). 99 patients had first ever isolate during the study period. Median observation time 7 years (0.1-14.9). 12 patients developed chronic infection. A Kaplan Meyer plot showed protection from chronic infection in up...

Antimicrobial, anti-inflammatory activities and toxicology of phenylethanoid glycosides from Monochasma savatieri Franch. ex Maxim.

Science.gov (United States)

Liu, Yan-li; He, Wen-jun; Mo, Li; Shi, Meng-fan; Zhu, Ying-ying; Pan, Shu; Li, Xiao-ran; Xu, Qiong-ming; Yang, Shi-lin

2013-09-16

Monochasma savatieri Franch. ex Maxim is used for treating many diseases in Traditional Chinese Medicine. The present study was designed to evaluate antibacterial, anti-inflammatory activities and toxicity of the total phenylethanoid glycosides from Monochasma savatieri Franch. ex Maxim (TPG). The antibacterial activity of TPG was checked by MIC and MBC in vitro; survival of mice with Pseudomonas aeruginosa or Staphylococcus aureus infection-induced sepsis was investigated to evaluate antibacterial activity of TPG in vivo. Additionally, antibacterial activities of TPG were also investigated in a Pseudomonas aeruginosa infection-induced pneumonia in the mice model. Cotton pellet induced granuloma and xylene induced ear swelling in mice models were used to quantify the anti-inflammatory activity. TPG showed a significant possess bacteriostatic properties against five bacteria strains at a concentration between 0.0625 and 16 mg/ml. Moreover, TPG has bactericidal activity against Pseudomonas aeruginosa, Streptococcus pneumoniae or Escherichia coli. TPG (60, 120, and 180 mg/kg) prolonged survival rate of mice with Pseudomonas aeruginosa or Staphylococcus aureus infection-induced sepsis. In addition, TPG (180 mg/kg) could reduce the bacterial colony-forming units in lung tissue. Furthermore, TPG (60-180 mg/kg) had significantly reduced xylene-induced ear edema and granulomat formation induced by cotton pellet at a dose-dependent manner. In addition, administration of TPG (1.5 g/kg) for 15 days did not result in toxicities in liver, kidney, spleen and thymus tissue in rats. These results indicated that TPG might be useful for the development of a novel treatment for respiratory infections or pneumonia caused by Pseudomonas aeruginosa or Staphylococcus aureus. © 2013 Elsevier Ireland Ltd. All rights reserved.

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

Science.gov (United States)

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

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.

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.

Nefropatía por Inmunoglobulina A: Guía de práctica clínica

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Alicia Fayad

2011-05-01

Full Text Available La nefropatía por Inmunoglobulina A (N.IgA es la causa más frecuente de enfermedad glomerular a nivel mundial, 15-50% de los pacientes presentan pérdida progresiva de la función renal en 10-20 años; el resto remisión clínica o hematuria/ proteinuria persistente. Su tratamiento óptimo es incierto. Nuestro objetivo fue desarrollar recomendaciones basadas en la evidencia a través de búsqueda en bases de datos Medline, Embase, Lilacs, Cochrane Trials Register. Los investigadores analizaron la calidad de los estudios independientemente, usando la Cochrane Renal Group checklist: aleatorización, carácter ciego, intención de tratar y pérdidas en el seguimiento. La evidencia se clasificó en niveles y la recomendación en grados, según el Centre for Evidence-Based Medicine, Oxford, con dos enfoques principales: Terapia inmunosupresora (corticoides, citostáticos, ciclosporina A y micofenolato mofetilo: Nivel I a, grado A. Terapia combinada con inmunosupresores en adultos: Nivel II b, grado B. Corticoides más ciclofosfamida o azatioprina en niños: Nivel II b, grado C. Ciclosporina y micofenolato-mofetilo: Nivel II b, grado B. Terapia no inmunosupresora: inhibidores del sistema renina-angiotensina (IEAC y/o bloqueantes del receptor de angiotensina II (BRAII, aceite de pescado, estatinas, antiplaquetarios y tonsilectomía: Nivel I a, grado A. Niños: IECA y BRAII con monitoreo de función renal y de nivel sérico de potasio: Nivel I b, grado B. En nefropatía progresiva, antiplaquetarios como tratamiento coadyuvante: Nivel I, grado C. Aceite de pescado como soporte adicionado de BRAII e IECA en pacientes con lesiones histológicas leves y baja reducción de la filtración glomerular: Nivel II b, grado B (no en niños. No hay evidencias para recomendar estatinas en niños; en mayores de 5 años con síndrome nefrótico e hipercolesterolemia usar sólo con monitoreo de fosfocreatin-kinasa sérica. No hay evidencias para recomendar la

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...

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.

Identification of a Signal That Mediates the Crosstalk Between Biosynthetic Gene Clusters for the Antibiotics 2,4-diacetylphloroglucinol and Pyoluteorin in Pseudomonas protegens Pf-5

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Pseudomonas protegens Pf-5 produces a broad spectrum of secondary metabolites with anti-microbial activity. The production of two of these metabolites, 2,4-diacetylphloroglucinol (DAPG) and pyoluteorin, is coordinately regulated. Our previous study indicated that phloroglucinol, an intermediate in t...

l-Methionine anti-biofilm activity against Pseudomonas aeruginosa is enhanced by the cystic fibrosis transmembrane conductance regulator potentiator, ivacaftor.

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Cho, Do-Yeon; Lim, Dong-Jin; Mackey, Calvin; Weeks, Christopher G; Peña Garcia, Jaime A; Skinner, Daniel; Grayson, Jessica W; Hill, Harrison S; Alexander, David K; Zhang, Shaoyan; Woodworth, Bradford A

2018-05-01

Biofilms may contribute to refractory chronic rhinosinusitis (CRS), as they lead to antibiotic resistance and failure of effective clinical treatment. l-Methionine is an amino acid with reported biofilm-inhibiting properties. Ivacaftor is a cystic fibrosis transmembrane conductance regulator (CFTR) potentiator with mild antimicrobial activity via inhibition of bacterial DNA gyrase and topoisomerase IV. The objective of this study was to evaluate whether co-treatment with ivacaftor and l-methionine can reduce the formation of Pseudomonas aeruginosa biofilms. P aeruginosa (PAO-1 strain) biofilms were studied in the presence of l-methionine and/or ivacaftor. For static biofilm assays, PAO-1 was cultured in a 48-well plate for 72 hours with stepwise combinations of these agents. Relative biofilm inhibitions were measured according to optical density of crystal violet stain at 590 nm. Live/dead assays (BacTiter-Glo™ assay, Promega) were imaged with laser scanning confocal microscopy. An agar diffusion test was used to confirm antibacterial effects of the drugs. l-Methionine (0.5 μM) significantly reduced PAO-1 biofilm mass (32.4 ± 18.0%; n = 4; p l-methionine (two-way analysis of variane, p = 0.0415) compared with corresponding concentrations of l-methionine alone. Ivacaftor enhanced the anti-biofilm activity of l-methionine against the PAO-1 strain of P aeruginosa. Further studies evaluating the efficacy of ivacaftor/l-methionine combinations for P aeruginosa sinusitis are planned. © 2018 ARS-AAOA, LLC.

Streptococcus pneumoniae and Pseudomonas aeruginosa pneumonia induce distinct host responses.

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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

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

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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...

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.

Genetic Detection of Pseudomonas spp. in Commercial Amazonian Fish

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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

Attenuation of quorum-sensing-dependent virulence factors and biofilm formation by medicinal plants against antibiotic resistant Pseudomonas aeruginosa

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P. Sankar Ganesh

2018-01-01

Full Text Available Pseudomonas aeruginosa use small signaling molecules such as acyl homoserine lactones (AHLs, which play an important role in release virulence factors and toxin for further establishment of host infection. Thus, involving with the QS system would provide alternative ways of preventing the pathogenicity. In the present study, totally six medicinal plants (Terminalia bellerica, Celastrus paniculatus, Kingiodendron pinnatum, Schleichera oleosa, Melastoma malabathricum, Garcinia gummi-gutta were screened for anti-QS activity using biomonitor strain of Chromobacterium violaceum CV12472. The primary screening of antimicrobial activity of all the plant extracts have inhibited the growth of tested bacterial species. Of these at the sub-minimum inhibitory concentration the methanol extract of T. bellerica (0.0625–0.5 mg/ml has significantly inhibited violacein production (20.07–66.22% in C. violaceum (CV12472. Consequently, the extract of T. bellerica has reduced the production of pyocyanin, exopolysaccharide and biofilm formation in P. aeruginosa strains. Fluorescence and scanning electron microscopy analysis confirmed the reduction of biofilm formation in P. aeruginosa strains when treated with T. bellerica. GC–MS analysis showed the active compounds inhibited the production of virulence factors of P. aeruginosa. The results suggest the possible use of this T. bellerica as an anti-QS and anti-biofilm agent to control Pseudomonas infection. Interference of QS provides an important means for the inhibition of bacterial virulence and thus aids in treatment strategies.

Nano-antibiotics in chronic lung infection therapy against Pseudomonas aeruginosa.

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Hadinoto, Kunn; Cheow, Wean Sin

2014-04-01

Antibiotic encapsulation into nanoparticle carriers has emerged as a promising inhaled antibiotic formulation for treatment of chronic Pseudomonas aeruginosa lung infection prevalent in chronic obstructive pulmonary diseases. Attributed to their prolonged lung retention, sustained antibiotic release, and mucus penetrating ability, antibiotic nanoparticles, or nano-antibiotics in short, can address the principal weakness of inhaled antibiotic solution, i.e. low antibiotic exposure in the vicinity of P. aeruginosa biofilm colonies resulting in diminished anti-pseudomonal efficacy after repeated uses. This review details the current state of development and limitations of the two most widely studied forms of nano-antibiotics, i.e. liposomes and polymer nanoparticles. Factors in their formulation that influence the anti-pseudomonal efficacy in vitro and in vivo, such as liposome's membrane rigidity, surface charge, size, and polymer hydrophobicity, are discussed. This review reveals that the superior anti-pseudomonal efficacy of liposomal antibiotics to free antibiotics has been clearly established when they are correctly formulated, with several liposomal antibiotic formulations are currently undergoing clinical trials. Liposomal antibiotics, nevertheless, are not without limitation due to their weak physicochemical stability. In contrast, only mucus penetrating ability of the more stable polymeric nano-antibiotics has been established, while their anti-pseudomonal efficacy has only been examined in vitro from which their superiority to free antibiotics has not been ascertained. Lastly, future research needs to bring liposome and polymer-based nano-antibiotics closer to their clinical realization are identified. Copyright © 2014 Elsevier B.V. All rights reserved.

Explore the full thick layer of corneal transplantation in the treatment of pseudomonas aeruginosa corneal ulcer infection

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Xin Wang

2015-02-01

Full Text Available AIM: To explore the feasibility, safety and effect of the full-thickness lamellar keratoplasty for the treatment of pseudomonas aeruginosa corneal ulcer. METHODS: Based on a retrospective non-controlled study, 25 patients were given the full-thickness lamellar keratoplasty for clinical diagnosis of pseudomonas aeruginosa infection and corneal ulcer medication conventional anti-gram-negative bacteria. Routine follow-up were carried out at postoperative 1wk; 1, 3, 6, 12, 18mo to observe the situation of corneal epithelial healing, recurrent infection, immune rejection, graft transparency and best corrected visual acuity, etc. At the 6 and 12mo postoperative, corneal endothelial cell density was reexamined.RESULTS: No patients because of Descemet's membrane rupture underwent penetrating keratoplasty surgery: One only in cases of bacterial infection after 1mo, once again did not cultivate a culture of bacteria pseudomonas aeruginosa, and the remaining 24 cases average follow-up 14±6mo, corneal graft were transparent, the cure rate was 96%. At the sixth month after surgery, there were 16 cases of eye surgery best corrected visual acuity ≥4.5, of which 3 cases ≥4.8. At the sixth month after surgery, the average corneal endothelial cell density 2 425±278/mm2; At 12mo postoperatively, it was 2 257± 326/mm2.CONCLUSION: Full-thickness lamellar keratoplasty is an effective method of pseudomonas aeruginosa infection in the treatment of corneal ulcers, corneal drying material glycerol can be achieved by visual effects.

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....

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...

Plant flavones enhance antimicrobial activity of respiratory epithelial cell secretions against Pseudomonas aeruginosa.

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Benjamin M Hariri

Full Text Available Flavones are a class of natural plant secondary metabolites that have anti-inflammatory and anti-bacterial effects. Some flavones also activate the T2R14 bitter taste receptor, which is expressed in motile cilia of the sinonasal epithelium and activates innate immune nitric oxide (NO production. Flavones may thus be potential therapeutics for respiratory infections. Our objective was to examine the anti-microbial effects of flavones on the common sinonasal pathogens Candida albicans, Staphylococcus aureus, and Pseudomonas aeruginosa, evaluating both planktonic and biofilm growth. Flavones had only very low-level antibacterial activity alone. They did not reduce biofilm formation, but did reduce production of the important P. aeruginosa inflammatory mediator and ciliotoxin pyocyanin. However, flavones exhibited synergy against P. aeruginosa in the presence of antibiotics or recombinant human lysozyme. They also enhanced the efficacy of antimicrobials secreted by cultured and primary human airway cells grown at air-liquid interface. This suggests that flavones may have anti-gram-negative potential as topical therapeutics when combined with antibiotics or in the context of innate antimicrobials secreted by the respiratory or other epithelia. This may have an additive effect when combined with T2R14-activated NO production. Additional studies are necessary to understand which flavone compounds or mixtures are the most efficacious.

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

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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 ).

Management and treatment of contact lens-related Pseudomonas keratitis

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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

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...

Attenuation of Pseudomonas aeruginosa quorum sensing, virulence and biofilm formation by extracts of Andrographis paniculata.

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Banerjee, Malabika; Moulick, Soumitra; Bhattacharya, Kunal Kumar; Parai, Debaprasad; Chattopadhyay, Subrata; Mukherjee, Samir Kumar

2017-12-01

Quorum-sensing (QS) is known to play an essential role in regulation of virulence factors and toxins during Pseudomonas aeruginosa infection which may frequently cause antibiotic resistance and hostile outcomes of inflammatory injury. Therefore, it is an urgent need to search for a novel agent with low risk of resistance development that can target QS and inflammatory damage prevention as well. Andrographis paniculata, a herbaceous plant under the family Acanthaceae, native to Asian countries and also cultivated in Scandinavia and some parts of Europe, has a strong traditional usage with its known antibacterial, anti-inflammatory, antipyretic, antiviral and antioxidant properties. In this study, three different solvent extracts (viz., chloroform, methanol and aqueous) of A. paniculata were examined for their anti-QS and anti-inflammatory activities. Study was carried out to assess the effect on some selected QS-regulatory genes at transcriptional level using Real Time-PCR. In addition, ability to attenuate MAPK pathways upon P. aeruginosa infection was performed to check its potential anti-inflammatory activity. Chloroform and methanol extracts showed significant reduction (p paniculata extracts inhibit QS in P. aeruginosa and exhibit anti-inflammatory activities, therefore it represents itself as a prospective therapeutic agent against P. aeruginosa infection. Copyright © 2017 Elsevier Ltd. All rights reserved.

Anti-allergic and anti-microbial activities of some Thai crops

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Supinya Tewtrakul

2008-07-01

Full Text Available Thirteen Thai crops including banana, okra, jackfruit, germinated rice, rambutan, durian, jampadah, huasa potato,tamarind, coconut, mango, fan palm fruit and dioscorea tuber were tested for anti-allergic effect using RBL-2H3 cells andanti-microbial activity. These 13 crops, some of which included different parts, e.g. skin, flesh, and seed, were extracted withfour solvents separately [(95% ethanol (EtOH, 50% EtOH, water (W and hot water (HW], respectively, to obtain 112extracts. Among these extracts, mango seed in 50% EtOH possessed the highest anti-allergic activity against antigen-inducedb-hexosaminidase release as a marker of degranulation in RBL-2H3 cells with an IC50 value of 7.5±0.8 mg/ml, followed bybanana (W, IC50 = 13.5±2.4 mg/ml, okra (W, IC50 = 13.6±3.1 mg/ml, jampadah skin (HW, IC50 = 13.8±3.9 mg/ml, tamarindseed coat (HW, IC50 = 14.2±3.1 mg/ml, jampadah flesh (W, IC50 = 14.6±3.1 mg/ml; whereas other crops possessed IC50values from 21.5->100 mg/ml. Moreover, the plants showing high anti-allergic effects were also possessed marked antibacterialactivity. Rambutan peel, mango peel, mango seed and tamarind seed coat exhibited appropriate anti-bacterialactivity against Staphylococcus aureus, Bacillus subtilis and Pseudomonas aeruginosa with MIC values ranging from 250-2,000 mg/ml, but did not show any effect towards Escherichia coli and Candida albicans. This study indicates that these Thaicrops may have potential as functional foods and neutraceuticals for treatment of allergy, allergy-related diseases and somebacterial infections.

Piper nigrum, Piper betle and Gnetum gnemon- Natural Food Sources with Anti-Quorum Sensing Properties

OpenAIRE

Tan, Li Ying; Yin, Wai-Fong; Chan, Kok-Gan

2013-01-01

Various parts of Piper nigrum, Piper betle and Gnetum gnemon are used as food sources by Malaysians. The purpose of this study is to examine the anti-quorum sensing (anti-QS) properties of P. nigrum, P. betle and G. gnemon extracts. The hexane, chloroform and methanol extracts of these plants were assessed in bioassays involving Pseudomonas aeruginosa PA01, Escherichia coli [pSB401], E. coli [pSB1075] and Chromobacterium violaceum CV026. It was found that the extracts of these three plants ha...

Scaffold of Selenium Nanovectors and Honey Phytochemicals for Inhibition of Pseudomonas aeruginosa Quorum Sensing and Biofilm Formation

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Prateeksha

2017-03-01

Full Text Available Honey is an excellent source of polyphenolic compounds that are effective in attenuating quorum sensing (QS, a chemical process of cell-to-cell communication system used by the opportunistic pathogen Pseudomonas aeruginosa to regulate virulence and biofilm formation. However, lower water solubility and inadequate bioavailability remains major concerns of these therapeutic polyphenols. Its therapeutic index can be improved by using nano-carrier systems to target QS signaling potently. In the present study, we fabricated a unique drug delivery system comprising selenium nanoparticles (SeNPs; non-viral vectors and polyphenols of honey (HP for enhancement of anti-QS activity of HP against P. aeruginosa PAO1. The developed selenium nano-scaffold showed superior anti-QS activity, anti-biofilm efficacy, and anti-virulence potential in both in-vitro and in-vivo over its individual components, SeNPs and HP. LasR is inhibited by selenium nano-scaffold in-vitro. Using computational molecular docking studies, we have also demonstrated that the anti-virulence activity of selenium nano-scaffold is reliant on molecular binding that occurs between HP and the QS receptor LasR through hydrogen bonding and hydrophobic interactions. Our preliminary investigations with selenium-based nano-carriers hold significant promise to improve anti-virulence effectiveness of phytochemicals by enhancing effective intracellular delivery.

Spoilage potential of Pseudomonas species isolated from goat milk.

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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

Pseudomonas aeruginosa PA14 pathogenesis in Caenorhabditis elegans.

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Kirienko, Natalia V; Cezairliyan, Brent O; Ausubel, Frederick M; Powell, Jennifer R

2014-01-01

The nematode Caenorhabditis elegans is a simple model host for studying the interaction between bacterial pathogens such as Pseudomonas aeruginosa and the metazoan innate immune system. Powerful genetic and molecular tools in both C. elegans and P. aeruginosa facilitate the identification and analysis of bacterial virulence factors as well as host defense factors. Here we describe three different assays that use the C. elegans-P. aeruginosa strain PA14 host-pathogen system. Fast Killing is a toxin-mediated death that depends on a diffusible toxin produced by PA14 but not on live bacteria. Slow Killing is due to an active infection in which bacteria colonize the C. elegans intestinal lumen. Liquid Killing is designed for high-throughput screening of chemical libraries for anti-infective compounds. Each assay has unique features and, interestingly, the PA14 virulence factors involved in killing are different in each assay.

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)

Mecanismos de acción de la inmunoglobulina humana en las enfermedades dermatológicas pediátricas Action mechanisms of human immunoglobulin in pediatric dermatological diseases

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Alain R. Rodríguez Orozco

2007-12-01

Full Text Available El uso de inmunomoduladores en dermatología pediátrica ha devenido necesidad de la práctica clínica contemporánea. Por otro lado, el continuo descubrimiento de moléculas involucradas en la fisiopatología de muchas enfermedades dermatológicas asociadas a trastornos inmunológicos obliga a revisar continuamente las aplicaciones de estos. El presente trabajo propone mostrar algunos mecanismos de acción que justifican el uso de la inmunoglobulina humana en algunas enfermedades dermatológicas pediátricas y facilita al médico la discusión sobre la conveniencia del uso de estas a la luz de la fisiopatología actual de estas enfermedades y del estado del paciente.The use of immunomodulators in pediatric dermatology has turned into a need of contemporary clinical practice. On the other hand, the continuous discovery of molecules involved in the physiopathology of many dermatological diseases associated with immunological disorders leads to the constant review of the application of these immunomodulators. This paper is aimed at showing some action mechanisms that justify the use of human immunoglobulin in some pediatric dermatological diseases and allows physicians to discuss the convenience of its utilization in the light of the present physiopathology of these diseases and of the patient’s state.

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....

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.

Piper nigrum, Piper betle and Gnetum gnemon--natural food sources with anti-quorum sensing properties.

Science.gov (United States)

Tan, Li Ying; Yin, Wai-Fong; Chan, Kok-Gan

2013-03-20

Various parts of Piper nigrum, Piper betle and Gnetum gnemon are used as food sources by Malaysians. The purpose of this study is to examine the anti-quorum sensing (anti-QS) properties of P. nigrum, P. betle and G. gnemon extracts. The hexane, chloroform and methanol extracts of these plants were assessed in bioassays involving Pseudomonas aeruginosa PA01, Escherichia coli [pSB401], E. coli [pSB1075] and Chromobacterium violaceum CV026. It was found that the extracts of these three plants have anti-QS ability. Interestingly, the hexane, chloroform and methanol extracts from P. betle showed the most potent anti-QS activity as judged by the bioassays. Since there is a variety of plants that serve as food sources in Malaysia that have yet to be tested for anti-QS activity, future work should focus on identification of these plants and isolation of the anti-QS compounds.

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.

Piper nigrum, Piper betle and Gnetum gnemon- Natural Food Sourcewith Anti-Quorum Sensing Properties

Directory of Open Access Journals (Sweden)

Li Ying Tan

2013-03-01

Full Text Available Various parts of Piper nigrum, Piper betle and Gnetum gnemon are used as food sources by Malaysians. The purpose of this study is to examine the anti-quorum sensing (anti-QS properties of P. nigrum, P. betle and G. gnemon extracts. The hexane, chloroform and methanol extracts of these plants were assessed in bioassays involving Pseudomonas aeruginosa PA01, Escherichia coli [pSB401], E. coli [pSB1075] and Chromobacterium violaceum CV026. It was found that the extracts of these three plants have anti-QS ability. Interestingly, the hexane, chloroform and methanol extracts from P. betle showed the most potent anti-QS activity as judged by the bioassays. Since there is a variety of plants that serve as food sources in Malaysia that have yet to be tested for anti-QS activity, future work should focus on identification of these plants and isolation of the anti-QS compounds.

Trombocitopenia de difícil manejo en niño preescolar con LES: Reporte de un caso

Directory of Open Access Journals (Sweden)

Mario Nicolás Albani Pérez

2010-08-01

Full Text Available El lupus eritematoso sistémico (LES es una enfermedad autoinmune del tejido conectivo, infrecuente en el sexo masculino y durante la infancia. La trombocitopenia se presenta en 15% de los casos de LES, y como forma de inicio es poco común. Se reporta el caso de preescolar masculino de 3 años de edad con inicio de enfermedad a los 18 meses de edad que presentó diarrea, rash cutáneo, equimosis y trombocitopenia; ameritando transfusión de concentrado plaquetario obteniendo mejoría parcial y en control con hematólogo. A los  2 años de edad reaparece equimosis y se diagnostica Púrpura Trombocitopénica Idiopática, tratado con inmunoglobulinas y esteroides sin respuesta satisfactoria. Es referido a Inmunología donde solicitan estudios y los resultados son compatibles con LES, por lo cual recibió prednisona sin respuesta satisfactoria. En Febrero de 2009, presenta epistaxis requiriendo hospitalización y tratamiento con inmunoglobulinas. En Mayo de 2009, presenta otorragia derecha ameritando nuevamente hospitalización y tratamiento con inmunoglobulinas. Se emplea Danazol con buena respuesta. En caso que en el futuro no ofrezca mejoría, se plantea el uso alternativo de ciclosporinas o anticuerpos monoclonales Anti-CD20 (Rituximab dejando como último recurso la esplenectomía. Se presenta el caso clínico considerando la importancia con respecto a la edad de presentación y el manejo no convencional que se debió adoptar para tratar al paciente.

Trombocitopenia de difícil manejo en niño preescolar con LES: Reporte de un caso

Directory of Open Access Journals (Sweden)

Mario Nicolás Albani Pérez

2009-01-01

Full Text Available El lupus eritematoso sistémico (LES es una enfermedad autoinmune del tejido conectivo, infrecuente en el sexo masculino y durante la infancia. La trombocitopenia se presenta en 15% de los casos de LES, y como forma de inicio es poco común. Se reporta el caso de preescolar masculino de 3 años de edad con inicio de enfermedad a los 18 meses de edad que presentó diarrea, rash cutáneo, equimosis y trombocitopenia, ameritando transfusión de concentrado plaquetario obteniendo mejoría parcial y en control con hematólogo. A los 2 años de edad reaparece equimosis y se diagnostica Púrpura Trombocitopénica Idiopática, tratado con inmunoglobulinas y esteroides sin respuesta satisfactoria. Es referido a Inmunología donde solicitan estudios y los resultados son compatibles con LES, por lo cual recibió prednisona sin respuesta satisfactoria. En Febrero de 2009, presenta epistaxis requiriendo hospitalización y tratamiento con inmunoglobulinas. En Mayo de 2009, presenta otorragia derecha ameritando nuevamente hospitalización y tratamiento con inmunoglobulinas. Se emplea Danazol con buena respuesta. En caso que en el futuro no ofrezca mejoría, se plantea el uso alternativo de ciclosporinas o anticuerpos monoclonales Anti- CD20 (Rituximab dejando como último recurso la esplenectomía. Se presenta el caso clínico considerando la importancia con respecto a la edad de presentación y el manejo no convencional que se debió adoptar para tratar al paciente.

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.

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 ...

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....

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.

A peptide from human β thymosin as a platform for the development of new anti-biofilm agents for Staphylococcus spp. and Pseudomonas aeruginosa.

Science.gov (United States)

Schillaci, Domenico; Spinello, Angelo; Cusimano, Maria Grazia; Cascioferro, Stella; Barone, Giampaolo; Vitale, Maria; Arizza, Vincenzo

2016-08-01

Conventional antibiotics might fail in the treatment of biofilm-associated infections causing infection recurrence and chronicity. The search for antimicrobial peptides has been performed with the aim to discover novel anti-infective agents active on pathogens in both planktonic and biofilm associated forms. The fragment 9-19 of human thymosin β4 was studied through 1 μs MD simulation. Two main conformations of the peptide were detected, both constituted by a central hydrophobic core and by the presence of peripheral charged residues suggesting a possible mechanism of interaction with two models of biological membranes, related to eukaryotic or bacterial membrane respectively. In addition, the peptide was chemically synthesized and its antimicrobial activity was tested in vitro against planktonic and biofilm form of a group of reference strains of Staphylococcus spp. and one P. aeruginosa strain. The human thymosin β4 fragment EIEKFDKSKLK showed antibacterial activity against staphylococcal strains and Pseudomonas aeruginosa ATCC 15442 at concentrations from 12.5 to 6.2 mg/ml and inhibited biofilm formation at sub-inhibitory concentrations (3.1-0.75 mg/ml). The activity of the fragment in inhibiting biofilm formation, could be due to the conformations highlighted by the MD simulations, suggesting its interaction with the bacterial membrane. Human thymosin β4 fragment can be considered a promising lead compound to develop novel synthetic or recombinant derivatives with improved pharmaceutical potential.

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...

Long-Chain 4-Aminoquinolines as Quorum Sensing Inhibitors in Serratia marcescens and Pseudomonas aeruginosa.

Science.gov (United States)

Aleksić, Ivana; Šegan, Sandra; Andrić, Filip; Zlatović, Mario; Moric, Ivana; Opsenica, Dejan M; Senerovic, Lidija

2017-05-19

Antibiotic resistance has become a serious global threat to public health; therefore, improved strategies and structurally novel antimicrobials are urgently needed to combat infectious diseases. Here we report a new type of highly potent 4-aminoquinoline derivatives as quorum sensing inhibitors in Serratia marcescens and Pseudomonas aeruginosa, exhibiting weak bactericidal activities (minimum inhibitory concentration (MIC) > 400 μM). Through detailed structure-activity study, we have identified 7-Cl and 7-CF 3 substituted N-dodecylamino-4-aminoquinolines (5 and 10) as biofilm formation inhibitors with 50% biofilm inhibition at 69 μM and 63 μM in S. marcescens and P. aeruginosa, respectively. These two compounds, 5 and 10, are the first quinoline derivatives with anti-biofilm formation activity reported in S. marcescens. Quantitative structure-activity relationship (QSAR) analysis identified structural descriptors such as Wiener indices, hyper-distance-path index (HDPI), mean topological charge (MTC), topological charge index (TCI), and log D(o/w) exp as the most influential in biofilm inhibition in this bacterial species. Derivative 10 is one of the most potent quinoline type inhibitors of pyocyanin production described so far (IC 50 = 2.5 μM). While we have demonstrated that 5 and 10 act as Pseudomonas quinolone system (PQS) antagonists, the mechanism of inhibition of S. marcescens biofilm formation with these compounds remains open since signaling similar to P. aeruginosa PQS system has not yet been described in Serratia and activity of these compounds on acylhomoserine lactone (AHL) signaling has not been detected. Our data show that 7-Cl and 7-CF 3 substituted N-dodecylamino-4-aminoquinolines present the promising scaffolds for developing antivirulence and anti-biofilm formation agents against multidrug-resistant bacterial species.

Piper nigrum, Piper betle and Gnetum gnemon- Natural Food Sources with Anti-Quorum Sensing Properties

Science.gov (United States)

Tan, Li Ying; Yin, Wai-Fong; Chan, Kok-Gan

2013-01-01

Various parts of Piper nigrum, Piper betle and Gnetum gnemon are used as food sources by Malaysians. The purpose of this study is to examine the anti-quorum sensing (anti-QS) properties of P. nigrum, P. betle and G. gnemon extracts. The hexane, chloroform and methanol extracts of these plants were assessed in bioassays involving Pseudomonas aeruginosa PA01, Escherichia coli [pSB401], E. coli [pSB1075] and Chromobacterium violaceum CV026. It was found that the extracts of these three plants have anti-QS ability. Interestingly, the hexane, chloroform and methanol extracts from P. betle showed the most potent anti-QS activity as judged by the bioassays. Since there is a variety of plants that serve as food sources in Malaysia that have yet to be tested for anti-QS activity, future work should focus on identification of these plants and isolation of the anti-QS compounds. PMID:23519352

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

The Effect of Silybin Encapsulated in Nanoparticles on oprM Gene Expression in Drug Resistant Isolates of Pseudomonas Aeruginosa

Directory of Open Access Journals (Sweden)

Aref Mohammadipour

2017-08-01

Full Text Available Abstract Background: Pseudomonas aeruginosa is an opportunistic nosocomial pathogen that using several classes of antibiotics to treat has been led to the emergence of multiple drug resistance. One of the drug resistance mechanisms in Pseudomonas aeruginosa is overexpression of mexXY-oprM efflux pump system. Silybin as main flavonolignan of silymarin extracted from Silybum marianum is a hepatoprotective agent that its anti-bacterial properties was studied, recently. In this study, the effect of combination of silybin and ciprofloxacin on oprM gene expression in clinical isolates of Pseudomonas aeruginosa was evaluated. Materials and Methods: In this study, seven ciprofloxacin resistant isolates of Pseudomonas aeruginosa were treated by ciprofloxacin (1/2MIC only (control sample and in the combination with silybin-encapsulated micelle (nanoparticles (test sample. After 24h, RNA extraction and cDNA synthesis were performed in silybin treated and un-treated cells and oprM gene expression was quantitatively investigated by realtime PCR method. Results: Results of this study showed that a silybin encapsulated in nanoparticles (400µg/ml induces death up to 50% in resistant isolates treated by ciprofloxacin (1/2MIC during 24h. Also, quantitative Real-Time PCR analysis revealed that silybin encapsulated in nanoparticles decreases the expression of oprM gene compared to silybin untreated cells. Conclusion: It seems that Decrease of oprM expression in resistant isolates lead to decrease of mexAB-oprM and mexXY-oprM in cell surface, subsequently decrease of antibiotic withdrawal to extracellular environment and increase of sensitivity to antibiotics.

Antivirulence activity of azithromycin in Pseudomonas aeruginosa

Directory of Open Access Journals (Sweden)

Francesco eImperi

2014-04-01

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

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...

Stereospecific oxidation of (R)- and (S)-1-indanol by naphthalene dioxygenase from Pseudomonas sp. strain NCIB 9816-4.

OpenAIRE

Lee, K; Resnick, S M; Gibson, D T

1997-01-01

A recombinant Escherichia coli strain which expresses naphthalene dioxygenase (NDO) from Pseudomonas sp. strain NCIB 9816-4 oxidized (S)-1-indanol to trans-(1S,3S)-indan-1,3-diol (95.5%) and (R)-3-hydroxy-1-indanone (4.5%). The same cells oxidized (R)-1-indanol to cis-1,3-indandiol (71%), (R)-3-hydroxy-1-indanone (18.2%), and cis-1,2,3-indantriol (10.8%). Purified NDO oxidized (S)-1-indenol to both syn- and anti-2,3-dihydroxy-1-indanol.

Stereospecific oxidation of (R)- and (S)-1-indanol by naphthalene dioxygenase from Pseudomonas sp. strain NCIB 9816-4.

Science.gov (United States)

Lee, K; Resnick, S M; Gibson, D T

1997-05-01

A recombinant Escherichia coli strain which expresses naphthalene dioxygenase (NDO) from Pseudomonas sp. strain NCIB 9816-4 oxidized (S)-1-indanol to trans-(1S,3S)-indan-1,3-diol (95.5%) and (R)-3-hydroxy-1-indanone (4.5%). The same cells oxidized (R)-1-indanol to cis-1,3-indandiol (71%), (R)-3-hydroxy-1-indanone (18.2%), and cis-1,2,3-indantriol (10.8%). Purified NDO oxidized (S)-1-indenol to both syn- and anti-2,3-dihydroxy-1-indanol.

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 ).

Antibacterial and anti-biofilm activity of ginger (Zingiber officinale (Roscoe ethanolic extract

Directory of Open Access Journals (Sweden)

Nikolić Miloš

2014-01-01

Full Text Available The antibacterial and anti-biofilm activity of ethanolic extract from the rhizome of Zingiber officinale were evaluated. In vitro antibacterial activity was investigated by microdilution method. Minimum inhibitory concentration (MIC and minimum bactericidal concentration (MBC have been determined. The values were in the range from 0.0024 to > 20 mg/ml. The most sensitive bacteria were Gram-positive bacteria: Staphylococcus aureus and Staphylococcus aureus ATCC 25923. Anti-biofilm activity was tested by crystal violet assay. Pseudomonas aeruginosa ATCC 27853, Proteus mirabilis and Escherichia coli ATCC 25922 were used as the test organisms. Ethanolic extract showed the best result on Proteus mirabilis biofilm where biofilm inhibitory concentration (BIC50 was 19 mg/ml.

Quorum-Quenching Human Designer Cells for Closed-Loop Control of Pseudomonas aeruginosa Biofilms.

Science.gov (United States)

Sedlmayer, Ferdinand; Jaeger, Tina; Jenal, Urs; Fussenegger, Martin

2017-08-09

Current antibiotics gradually lose their efficacy against chronic Pseudomonas aeruginosa infections due to development of increased resistance mediated by biofilm formation, as well as the large arsenal of microbial virulence factors that are coordinated by the cell density-dependent phenomenon of quorum sensing. Here, we address this issue by using synthetic biology principles to rationally engineer quorum-quencher cells with closed-loop control to autonomously dampen virulence and interfere with biofilm integrity. Pathogen-derived signals dynamically activate a synthetic mammalian autoinducer sensor driving downstream expression of next-generation anti-infectives. Engineered cells were able to sensitively score autoinducer levels from P. aeruginosa clinical isolates and mount a 2-fold defense consisting of an autoinducer-inactivating enzyme to silence bacterial quorum sensing and a bipartite antibiofilm effector to dissolve the biofilm matrix. The self-guided cellular device fully cleared autoinducers, potentiated bacterial antibiotic susceptibility, substantially reduced biofilms, and alleviated cytotoxicity to lung epithelial cells. We believe this strategy of dividing otherwise coordinated pathogens and breaking up their shielded stronghold represents a blueprint for cellular anti-infectives in the postantibiotic era.

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)

Piper betle leaf extract affects the quorum sensing and hence virulence of Pseudomonas aeruginosa PAO1.

Science.gov (United States)

Datta, Siraj; Jana, Debanjan; Maity, Tilak Raj; Samanta, Aveek; Banerjee, Rajarshi

2016-06-01

Quorum sensing (QS) plays an important role in virulence of Pseudomonas aeruginosa, blocking of QS ability are viewed as viable antimicrobial chemotherapy and which may prove to be a safe anti-virulent drug. Bioactive components from Piper betle have been reported to possess antimicrobial ability. This study envisages on the anti-QS properties of ethanolic extract of P. betle leaf (PbLE) using P. aeruginosa PAO1 as a model organism. A marked reduction in swarming, swimming, and twitching ability of the bacteria is demonstrated in presence of PbLE. The biofilm and pyocyanin production also shows a marked reduction in presence of PbLE, though it does not affect the bacterial growth. Thus, the studies hint on the possible effect of the bioactive components of PbLE on reducing the virulent ability of the bacteria; identification of bioactive compounds should be investigated further.

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...

Anti-infective properties of Lactobacillus fermentum against Staphylococcus aureus and Pseudomonas aeruginosa.

Science.gov (United States)

Varma, Parvathi; Nisha, N; Dinesh, Kavitha R; Kumar, Anil V; Biswas, Raja

2011-01-01

Surgical wounds and implant-associated Staphylococcus aureus and Pseudomonas aeruginosa infections are often difficult to treat because of limited susceptibility of several of these strains to conventional antibiotics. As a result, there is a constant need for new alternative drugs. The aim of this study was to investigate the antimicrobial properties of Lactobacillus fermentum, a probiotic bacterium, which we have isolated from colonic biopsies. The inhibition of S. aureus and P. aeruginosa growth was evaluated by coincubating with L. fermentum strains. Growth inhibition was tested for several of their clinical isolates using agar well diffusion assays. For biofilm assay S. aureus and P. aeruginosa were grown on the glass slides and in 96-well plates in presence of 2.5 μg/ml culture filtrate of L. fermentum. Biofilms were photographed using confocal microscope or stained with 0.1% crystal violet. Reduction in the cytotoxicity of S. aureus and P. aeruginosa was observed in presence of 2.5 μg/ml L. fermentum-spent media. Using in vitroexperiments, we showed that L. fermentum-secreted compound(s) inhibits the growth, cytotoxicity and biofilm formation of several S. aureus and P. aeruginosa strains. Compound(s) present in the culture supernatant of L. fermentum may have promising applications in treating hospital-acquired infections. Copyright © 2011 S. Karger AG, Basel.

Inhibition of Quorum Sensing-Controlled Virulence Factor Production in Pseudomonas aeruginosa PAO1 by Ayurveda Spice Clove (Syzygium Aromaticum Bud Extract

Directory of Open Access Journals (Sweden)

Kok-Gan Chan

2012-03-01

Full Text Available Quorum sensing controls the virulence determinants in most proteobacteria. In this work, the hexane, chloroform and methanol extracts of an Ayurveda spice, namely clove (Syzygium aromaticum, shown anti-quorum sensing activity. Hexane and methanol extracts of clove inhibited the response of C. violaceum CV026 to exogenously supplied N‑hexanoylhomoserine lactone, in turn preventing violacein production. Chloroform and methanol extracts of clove significantly reduced bioluminescence production by E. coli [pSB1075] grown in the presence of N-(3-oxododecanoyl-L-homoserine lactone. We demonstrated that clove extract inhibited quorum sensing-regulated phenotypes in Pseudomonas aeruginosa PA01, including expression of lecA::lux (by hexane extract, swarming (maximum inhibition by methanol extract, pyocyanin (maximum inhibition by hexane extract. This study shows that the presence of natural compounds that exhibit anti-quorum sensing activity in the clove extracts may be useful as the lead of anti-infective drugs.

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

Study on Hydro-Alcoholic Extract Effect of Pomegranate Peel on Pseudomonas aeruginosa Biofilm Formation

Directory of Open Access Journals (Sweden)

R. Habibipour

2015-10-01

Full Text Available Introduction & Objective: Microorganisms form biomass as biofilm in response to many factors, in order to adapt to hostile extracellular environments and biocides. Using different herbal compounds are of those strategies to deal with biofilm. It has been proved that plants extracts such as pomegranate, raspberry and chamomile essential oils have anti-biofilm effects. This study aimed to evaluate the effect of different concentrations of black peel pomegranate ex-tract on Pseudomonas aeruginosa biofilm formation. Materials & Methods: In this experimental research the anti-biofilm effect, reducing the amount of biofilm formation and growth kinetics of Pseudomonas aeruginosa in different treatments was measured by microtiter and plate colorimetric crystal violet method. Biofilm formation was also examined using a microscope. Statistical analysis of data obtained from the reading of the ELISA was performed using SPSS software, P value 0.05. Results: Findings of this study showed that bacteria cannot form any biofilm in first 6 hours of incubation, in all treatments. The amount of biofilm formation after 12 hours in 0.01 and 0.05 g/ mL treatments were medium. Among treatments, after 18 and 24 hours of incubation 0.001 g/ mL concentration of pomegranate peel extract had medium and strong inhibitory effect on biofilm formation, respectively. Conclusion: Results of this study showed that biofilm formation and biofilm reduction percent-age is directly related to the duration of exposure of bacteria that could be due to the different phases of growth. Growth kinetics study also revealed that in the majority of treatments the growth was incremental up to about 15 hours and decrement afterwards due to the effective-ness of different treatments. After 18 hours, treatments have greatest influence on biofilm formation. The foregoing has been fully confirmed by the results of microscopic slides. (Sci J Hamadan Univ Med Sci 2015; 22 (3: 195-202

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

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.

Manejo médico de la exposición al virus de la hepatitis B

OpenAIRE

Mancel Martínez; Craig Shapiro; Ana Bracho; Fernando De La Hoz

1991-01-01

Se hace una revisión de los conocimientos actuales sobre el tratamiento en el caso de una probable exposición al virus de la hepatitis B. Se presenta la pormenorización de las diferentes clases de exposición así como la indicación y dosificación de la inmunoglobulina específica y de la vacuna anti-hepatitis B. Esta revisión tiene como fundamento las recomendaciones del CDC de Atlanta y de la Organización Mundial de la Salud.

Manejo médico de la exposición al virus de la hepatitis B

Directory of Open Access Journals (Sweden)

Mancel Martínez

1991-12-01

Full Text Available Se hace una revisión de los conocimientos actuales sobre el tratamiento en el caso de una probable exposición al virus de la hepatitis B. Se presenta la pormenorización de las diferentes clases de exposición así como la indicación y dosificación de la inmunoglobulina específica y de la vacuna anti-hepatitis B. Esta revisión tiene como fundamento las recomendaciones del CDC de Atlanta y de la Organización Mundial de la Salud.

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

Synthesis and pharmacological evaluation of pyrazolo[4,3-c]cinnoline derivatives as potential anti-inflammatory and antibacterial agents.

Science.gov (United States)

Tonk, Rajiv Kumar; Bawa, Sandhya; Chawla, Gita; Deora, Girdhar Singh; Kumar, Suresh; Rathore, Vandana; Mulakayala, Naveen; Rajaram, Azad; Kalle, Arunasree M; Afzal, Obaid

2012-11-01

A series of pyrazolo[4,3-c]cinnoline derivatives was synthesized, characterized and evaluated for anti-inflammatory and antibacterial activity. Test compounds that exhibited good anti-inflammatory activity were further screened for their ulcerogenic and lipid peroxidation activity. Compounds 4d and 4l showed promising anti-inflammatory activity with reduced ulcerogenic and lipid peroxidation activity when compared to naproxen. Docking results of these two compounds with COX-2 (PDB ID: 1CX2) also exhibited a strong binding profile. Among the test derivatives, compound 4i displayed significant antibacterial property against gram-negative (Escherichia coli and Pseudomonas aeruginosa) and gram-positive (Staphylococcus aureus) bacteria. However, compound 4b emerged as the best dual anti-inflammatory-antibacterial agent in the present study. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

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.).

Antibiotic resistance in Pseudomonas aeruginosa biofilms: towards the development of novel anti-biofilm therapies.

Science.gov (United States)

Taylor, Patrick K; Yeung, Amy T Y; Hancock, Robert E W

2014-12-10

The growth of bacteria as structured aggregates termed biofilms leads to their protection from harsh environmental conditions such as physical and chemical stresses, shearing forces, and limited nutrient availability. Because of this highly adapted ability to survive adverse environmental conditions, bacterial biofilms are recalcitrant to antibiotic therapies and immune clearance. This is particularly problematic in hospital settings where biofilms are a frequent cause of chronic and device-related infections and constitute a significant burden on the health-care system. The major therapeutic strategy against infections is the use of antibiotics, which, due to adaptive resistance, are often insufficient to clear biofilm infections. Thus, novel biofilm-specific therapies are required. Specific features of biofilm development, such as surface adherence, extracellular matrix formation, quorum sensing, and highly regulated biofilm maturation and dispersal are currently being studied as targets to be exploited in the development of novel biofilm-specific treatments. Using Pseudomonas aeruginosa for illustrative purposes, this review highlights the antibiotic resistance mechanisms of biofilms, and discusses current research into novel biofilm-specific therapies. Copyright © 2014 Elsevier B.V. All rights reserved.

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, ...

Panax ginseng has anti-infective activity against opportunistic pathogen Pseudomonas aeruginosa by inhibiting quorum sensing, a bacterial communication process critical for establishing infection

DEFF Research Database (Denmark)

Song, Z; Kong, K F; Wu, H

2010-01-01

Virulent factors produced by pathogens play an important role in the infectious process, which is regulated by a cell-to-cell communication mechanism called quorum sensing (QS). Pseudomonas aeruginosa is an important opportunistic human pathogen, which causes infections in patients with compromis...

A Novel Insight into Dehydroleucodine Mediated Attenuation of Pseudomonas aeruginosa Virulence Mechanism

Directory of Open Access Journals (Sweden)

S. Mustafi

2015-01-01

Full Text Available Increasing resistance of Pseudomonas aeruginosa (P. aeruginosa to conventional treatments demands the search for novel therapeutic strategies. In this study, the antimicrobial activity of dehydroleucodine (DhL, a sesquiterpene lactone obtained from Artemisia (A. douglasiana, was screened against several pathogenic virulence effectors of P. aeruginosa. In vitro, minimum inhibitory concentration of DhL was determined against P. aeruginosa strains PAO1, PA103, PA14, and multidrug resistant clinical strain, CDN118. Results showed that DhL was active against each strain where PAO1 and PA103 showed higher susceptibility (MIC 0.48 mg/mL as compared to PA14 (MIC 0.96 mg/mL and CDN118 (MIC 0.98 mg/mL. Also, when PAO1 strain was grown in the presence of DhL (MIC50, 0.12 mg/mL, a delay in the generation time was noticed along with significant inhibition of secretory protease and elastase activities, interruption in biofilm attachment phase in a stationary culture, and a significant decline in Type III effector ExoS. At MIC50, DhL treatment increased the sensitivity of P. aeruginosa towards potent antibiotics. Furthermore, treatment of P. aeruginosa with DhL prevented toxin-induced apoptosis in macrophages. These observations suggest that DhL activity was at the bacterial transcriptional level. Hence, antimicrobial activity of DhL may serve as leads in the development of new anti-Pseudomonas pharmaceuticals.

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.

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 ...

Mechanisms of humoral immune response against Pseudomonas aeruginosa biofilm infection in cystic fibrosis

DEFF Research Database (Denmark)

Mauch, Renan Marrichi; Jensen, Peter Østrup; Moser, Claus

2018-01-01

P. aeruginosa chronic lung infection is the major cause of morbidity and mortality in patients with cystic fibrosis (CF), and is characterized by a biofilm mode of growth, increased levels of specific IgG antibodies and immune complex formation. However, despite being designed to combat...... this infection, such elevated humoral response is not associated with clinical improvement, pointing to a lack of anti-pseudomonas effectiveness. The mode of action of specific antibodies, as well as their structural features, and even the background involving B-cell production, stimulation and differentiation...... into antibody-producing cells in the CF airways are poorly understood. Thus, the aim of this review is to discuss studies that have addressed the intrinsic features of the humoral immune response and provide new insights regarding its insufficiency in the CF context....

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.

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...

Controlled assembly of silver nano-fluid in Heliotropium crispum extract: A potent anti-biofilm and bactericidal formulation

Science.gov (United States)

Khan, Faria; Hashmi, Muhammad Uzair; Khalid, Nauman; Hayat, Muhammad Qasim; Ikram, Aamer; Janjua, Hussnain A.

2016-11-01

The study describes the optimized method for silver nanoparticle (AgNPs) synthesis using Heliotropium crispum (HC) plant extract. Optimization of physicochemical parameters resulted in stable and rapidly assembled AgNPs. FTIR results suggest presence of plant phytochemicals that helped in the reduction, stabilization and capping of AgNPs. The assembled Ag nano-composites displayed the peak surface plasmon resonance (SPR) around 428 nm. The presence of uniquely assembled Ag-biomolecule composites, cap and stabilize nanoparticles in aqueous plant suspension. Spherical, uniform-shaped AgNPs with low poly-dispersion and average particle size of 42 nm and was determined through dynamic light scattering (DLS) and scanning election microscopy (SEM) which present robust interaction with microbes. The study also evaluates the antimicrobial and anti-biofilm properties of biologically synthesized AgNPs on clinical isolates of MRSA, Pseudomonas aeruginosa and Acinetobacter baumannii. Minimum inhibitory concentration (0.5 mg mL-1) of nanoparticles that presented bactericidal effect was made through inhibition assays on bacterial strains. The concentration which presented potent bactericidal response was then evaluated through growth inhibition in liquid medium for anti-biofilm studies at 2.0 mg mL-1. HC-Ag nanoparticles mediated anti-biofilm effects on Pseudomonas aeruginosa was revealed through SEM. Complete breakdown of biofilm's extracellular polymeric substances resulted after incubation with AgNPs. Peptidoglycan cell wall destruction was also revealed on planktonic bacterial images after 24 h of incubation.

Antimicrobial resistance of Pseudomonas spp. isolated from wastewater and wastewater-impacted marine coastal zone.

Science.gov (United States)

Luczkiewicz, Aneta; Kotlarska, Ewa; Artichowicz, Wojciech; Tarasewicz, Katarzyna; Fudala-Ksiazek, Sylwia

2015-12-01

In this study, species distribution and antimicrobial susceptibility of cultivated Pseudomonas spp. were studied in influent (INF), effluent (EFF), and marine outfall (MOut) of wastewater treatment plant (WWTP). The susceptibility was tested against 8 antimicrobial classes, active against Pseudomonas spp.: aminoglycosides, carbapenems, broad-spectrum cephalosporins from the 3rd and 4th generation, extended-spectrum penicillins, as well as their combination with the β-lactamase inhibitors, monobactams, fluoroquinolones, and polymyxins. Among identified species, resistance to all antimicrobials but colistin was shown by Pseudomonas putida, the predominant species in all sampling points. In other species, resistance was observed mainly against ceftazidime, ticarcillin, ticarcillin-clavulanate, and aztreonam, although some isolates of Pseudomonas aeruginosa, Pseudomonas fluorescens, Pseudomonas pseudoalcaligenes, and Pseudomonas protegens showed multidrug-resistance (MDR) phenotype. Among P. putida, resistance to β-lactams and to fluoroquinolones as well as multidrug resistance become more prevalent after wastewater treatment, but the resistance rate decreased in marine water samples. Obtained data, however, suggests that Pseudomonas spp. are equipped or are able to acquire a wide range of antibiotic resistance mechanisms, and thus should be monitored as possible source of resistance genes.

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

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.

Multiple antibiotic susceptibility of polyphosphate kinase mutants (ppk1 and ppk2 from Pseudomonas aeruginosa PAO1 as revealed by global phenotypic analysis

Directory of Open Access Journals (Sweden)

Javiera Ortiz-Severín

2015-01-01

Full Text Available BACKGROUND: Pseudomonas aeruginosa is known to be a multidrug resistant opportunistic pathogen. Particularly, P. aeruginosa PAO1 polyphosphate kinase mutant (ppk1 is deficient in motility, quorum sensing, biofilm formation and virulence FINDINGS: By using Phenotypic Microarrays (PM we analyzed near 2000 phenotypes of P. aeruginosa PAO1 polyP kinase mutants (ppk1 and ppk2. We found that both ppk mutants shared most of the phenotypic changes and interestingly many of them related to susceptibility toward numerous and different type of antibiotics such as Ciprofloxacin, Chloramphenicol and Rifampicin CONCLUSIONS: Combining the fact that ppk1 mutants have reduced virulence and are more susceptible to antibiotics, polyP synthesis and particularly PPK1, is a good target for the design of molecules with anti-virulence and anti-persistence properties.

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...

The Effects of Chinese Herbal Medicines on the Quorum Sensing-Regulated Virulence in Pseudomonas aeruginosa PAO1

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Yee Meng Chong

2018-04-01

Full Text Available The quorum sensing (QS system has been used by many opportunistic pathogenic bacteria to coordinate their virulence determinants in relation to cell-population density. As antibiotic-resistant bacteria are on the rise, interference with QS has been regarded as a novel way to control bacterial infections. As such, many plant-based natural products have been widely explored for their therapeutic roles. These natural products may contain anti-QS compounds that could block QS signals generation or transmission to combat QS pathogens. In this study, we report the anti-QS activities of four different Chinese herbal plant extracts: Poria cum Radix pini, Angelica dahurica, Rhizoma cibotii and Schizonepeta tenuifolia, on Pseudomonas aeruginosa PAO1. All the plants extracted using hexane, chloroform and methanol were tested and found to impair swarming motility and pyocyanin production in P. aeruginosa PAO1, particularly by Poria cum Radix pini. In addition, all the plant extracts also inhibited violacein production in C. violaceum CV026 up to 50% while bioluminescence activities were reduced in lux-based E. coli biosensors, pSB401 and pSB1075, up to about 57%. These anti-QS properties of the four medicinal plants are the first documentation that demonstrates a potential approach to attenuate pathogens’ virulence determinants.

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

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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.

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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

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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

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

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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.

High-throughput screening for novel anti-infectives using a C. elegans pathogenesis model.

Science.gov (United States)

Conery, Annie L; Larkins-Ford, Jonah; Ausubel, Frederick M; Kirienko, Natalia V

2014-03-14

In recent history, the nematode Caenorhabditis elegans has provided a compelling platform for the discovery of novel antimicrobial drugs. In this protocol, we present an automated, high-throughput C. elegans pathogenesis assay, which can be used to screen for anti-infective compounds that prevent nematodes from dying due to Pseudomonas aeruginosa. New antibiotics identified from such screens would be promising candidates for treatment of human infections, and also can be used as probe compounds to identify novel targets in microbial pathogenesis or host immunity. Copyright © 2014 John Wiley & Sons, Inc.

Facial Nerve Paralysis seen in Pseudomonas sepsis with ecthyma gangrenosum

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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

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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...

Antioxidant and Anti-quorum Sensing Potential of Acer monspessulanum subsp. monspessulanum Extracts.

Science.gov (United States)

Ceylan, Ozgur; Sahin, Mehtap Donmez; Akdamar, Gultekin

2016-10-01

In this study, anti-quorum sensing, and antioxidant activities, and chemical composition of Acer monspessulanum subsp. monspessulanum extracts were evaluated. Determination of the antioxidant activity was revealed by DPPH radical scavenging activity, the total phenolic content assay, and the β -carotene/linoleic acid assay. The detection of phenolic compounds was determined using RP-HPLC. Anti-quorum sensing activity and violacein inhibition activity were determined using Chromobacterium violaceum CV026 and C. violaceum ATCC 112 472, respectively. The determination of anti-swarming activity was carried out with Pseudomonas aeruginosa PA01. In DPPH and total phenolic content assays, the water extract exhibited good antioxidant activity. In the β -carotene-linoleic acid assay, ethyl acetate and ethanol extracts exhibited good lipid peroxidation inhibition activity, demonstrating 96.95 ± 0.03 % and 95.35 ± 0.00 % at 2.5 mg/mL concentrations, respectively. The predominant phenolic compounds of the extracts were determined as rutin, naringin, catechin hydrate, quercetin, and protocatechuic acid. Ethyl acetate and ethanol extracts were found to contain a high level of violacein inhibition and anti-quorum sensing activity. The ethanol extract also showed weak anti-swarming activity. In this first study that used Acer monspessulanum subsp. monspessulanum extracts, it was revealed that the water extract has antioxidant activity and the ethanol and ethyl acetate extracts have anti-quorum sensing activity depending on the phenolic compounds that it contained. Georg Thieme Verlag KG Stuttgart · New York.

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.

Biogenic synthesis of silver nanoparticle by using secondary metabolites from Pseudomonas aeruginosa DM1 and its anti-algal effect on Chlorella vulgaris and Chlorella pyrenoidosa.

Science.gov (United States)

Kumari, Rima; Barsainya, Manjari; Singh, Devendra Pratap

2017-02-01

Biogenic synthesis of silver nanoparticles (AgNPs) using extracellular metabolites from the bacterium Pseudomonas aeruginosa DM1 offers an eco-friendly and sustainable way of metal nanoparticle synthesis. The present work highlights the biotransformation of silver nitrate solution into AgNP, mediated by extracellular secondary metabolite pyoverdine, a siderophore produced by P. aeruginosa. The bioreduction of silver ions into AgNPs by using pyoverdine was recorded in terms of Fourier transform infrared spectroscopy (FTIR) analysis and color change in the reaction mixture (AgNO 3 + pyoverdine) from pale yellow to dark brown with absorption maxima at 415 nm. The results of X-ray diffraction (XRD) analysis of AgNPs showed its crystalline face-centered cubic structure. The scanning electron microscopy (SEM) and transmission electron microscopy (TEM) pictures of AgNPs showed spherical morphology of AgNP in the range of 45-100 nm, with tendency of agglomerations. The energy-dispersive X-ray (EDX) analysis of particles provided strong signal of elemental silver with few minor peaks of other impurities. The present approach offers a unique in vitro method of metal nanoparticle synthesis by exogenously produced bacterial secondary metabolites, where direct contact between the toxic metal and biological resource material can be avoided. The biologically synthesized AgNPs are found to have anti-algal effects against two species of Chlorella (Chlorella vulgaris and Chlorella pyenoidosa), as indicated by zone of growth inhibition on algal culture plates. Further results exhibit concentration-dependent progressive inhibition of chlorophyll content in the algal cells by AgNPs, confirming the algicidal effect of AgNPs.

Synthesized zinc peroxide nanoparticles (ZnO2-NPs): a novel antimicrobial, anti-elastase, anti-keratinase, and anti-inflammatory approach toward polymicrobial burn wounds.

Science.gov (United States)

Ali, Sameh Samir; Morsy, Reda; El-Zawawy, Nessma Ahmed; Fareed, Mervat F; Bedaiwy, Mohamed Yaser

2017-01-01

Increasing of multidrug resistance (MDR) remains an intractable challenge for burn patients. Innovative nanomaterials are also in high demand for the development of new antimicrobial biomaterials that inevitably have opened new therapeutic horizons in medical approaches and lead to many efforts for synthesizing new metal oxide nanoparticles (NPs) for better control of the MDR associated with the polymicrobial burn wounds. Recently, it seems that metal oxides can truly be considered as highly efficient inorganic agents with antimicrobial properties. In this study, zinc peroxide NPs (ZnO 2 -NPs) were synthesized using the co-precipitation method. Synthesized ZnO 2 -NPs were characterized by X-ray diffraction, Fourier transformed infrared, transmission electron microscopy, thermogravimetric analysis, differential scanning calorimetry, and ultraviolet-visible spectroscopy. The characterization techniques revealed synthesis of the pure phase of non-agglomerated ZnO 2 -NPs having sizes in the range of 15-25 nm with a transition temperature of 211°C. Antimicrobial activity of ZnO 2 -NPs was determined against MDR Pseudomonas aeruginosa (PA) and Aspergillus niger (AN) strains isolated from burn wound infections. Both strains, PA6 and AN4, were found to be more susceptible strains to ZnO 2 -NPs. In addition, a significant decrease in elastase and keratinase activities was recorded with increased concentrations of ZnO 2 -NPs until 200 µg/mL. ZnO 2 -NPs revealed a significant anti-inflammatory activity against PA6 and AN4 strains as demonstrated by membrane stabilization, albumin denaturation, and proteinase inhibition. Moreover, the results of in vivo histopathology assessment confirmed the potential role of ZnO 2 -NPs in the improvement of skin wound healing in the experimental animal models. Clearly, the synthesized ZnO 2 -NPs have demonstrated a competitive capability as antimicrobial, anti-elastase, anti-keratinase, and anti-inflammatory candidates, suggesting that the

Pseudomonas aeruginosa necrotizing chondritis complicating high helical ear piercing case report: clinical and public health perspectives.

Science.gov (United States)

Sandhu, Amonpreet; Gross, Melissa; Wylie, John; Van Caeseele, Paul; Plourde, Pierre

2007-01-01

Auricular or high helical ear piercing is an increasingly widespread fashion trend that is associated with an increased risk of potentially serious post-piercing complications such as auricular perichondritis. An 11-year-old girl developed severe auricular perichondritis following piercing of the upper helical cartilage of her ear at a hairdressing salon. Four days post piercing, she returned to the same salon for a haircut during which the pierced site was manipulated. She presented to her family physician and was treated unsuccessfully with oral cephalexin. She was then referred to an infectious diseases consultant and received antipseudomonal intravenous antibiotics with subsequent resolution. She also required debridement and removal of necrotic cartilage. Public health investigation evaluated potential sources of infection including the piercing gun, disinfectant solutions, and hair cutting spray water bottles. Final culture results of the ear helical aspirate grew Pseudomonas aeruginosa. Pseudomonas aeruginosa was also cultured from one of the water bottles used to wet her hair during the haircut. Although the pseudomonal strains from the water bottle were different than the infecting one, this contamination presents a potential source of wound infection. Damage to the helical cartilage caused by the piercing gun may also have contributed to this infection. Initial empiric antibiotic therapy for these kinds of infection must include anti-pseudomonal coverage. Auricular or high helical ear piercing using a piercing gun is not recommended.

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.

SYNTHESIS, CHARACTERIZATION AND ANTI-BACTERIAL ACTIVITY OF CERTAIN 2,3,4,5-TETRAHYDROPYRIDAZINONE ANALOGUES

Directory of Open Access Journals (Sweden)

Gaurav ALANG

2011-04-01

Full Text Available In the present study, six new derivatives of PYridazinone were synthesized and evaluate their anti-bacterial activity. The experimental work involves the synthesis of benzoyl propionic acid (a, then 6-phenyl-2,3,4,5-tetrahydro pyridazin-3-one (b which was then condensed with various, aldehydes to form respective derivatives, AH the synthesized compounds were identified by IR, 1HNMR and antimicrobial activity was performed on the compounds synthesized against Staphylococcus aureus (MTCC 737, Staphylococcus epidermidis (MTCC 3615, Pseudomonas aeruginosa (MTCC 424 and Escherichia coli (MTCC 1687

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

Inhibitory activity of Iranian plant extracts on growth and biofilm formation by Pseudomonas aeruginosa

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Mansouri, S.

2013-01-01

Full Text Available Aims: Pseudomonas aeruginosa is a drug resistance opportunistic bacterium. Biofilm formation is key factor for survivalof P. aeruginosa in various environments. Polysaccharides may be involved in biofilm formation. The purpose of thisstudy was to evaluate antimicrobial and anti-biofilm activities of seven plant extracts with known alpha-glucosidaseinhibitory activities on different strains of P. aeruginosa.Methodology and results: Plants were extracted with methanol by the maceration method. Antimicrobial activities weredetermined by agar dilution and by growth yield as measured by OD560nm of the Luria Bertani broth (LB culture with orwithout extracts. In agar dilution method, extracts of Quercus infectoria inhibited the growth of all, while Myrtuscommunis extract inhibited the growth of 3 out of 8 bacterial strains with minimum inhibitory concentration (MIC of 1000μg/mL. All extracts significantly (p≤0.003 reduced growth rate of the bacteria in comparison with the control withoutextracts in LB broth at sub-MIC concentrations (500 μg/mL. All plant extracts significantly (p≤0.003 reduced biofilmformation compared to the controls. Glycyrrhiza glabra and Q. infectoria had the highest anti-biofilm activities. Nocorrelation between the alpha-glucosidase inhibitory activity with growth or the intensity of biofilm formation was found.Conclusion, significance and impact of study: Extracts of Q. infectoria and M. communis had the most antimicrobial,while Q. infectoria and G. glabra had the highest anti-biofilm activities. All plant extracts had anti-biofilm activities withmarginal effect on growth, suggesting that the mechanisms of these activities are unrelated to static or cidal effects.Further work to understand the relation between antimicrobial and biofilm formation is needed for development of newmeans to fight the infectious caused by this bacterium in future.

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....

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

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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

Directory of Open Access Journals (Sweden)

Fatimah Fatimah

2012-02-01

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

Phloroglucinols from anti-microbial deposit-resins of Australian stingless bees (Tetragonula carbonaria).

Science.gov (United States)

Massaro, C Flavia; Smyth, Thomas J; Smyth, W Franklin; Heard, Tim; Leonhardt, Sara D; Katouli, Mohammad; Wallace, Helen M; Brooks, Peter

2015-01-01

Stingless bees accumulate deposits of plant resins that are mixed with beeswax to produce propolis. Previous studies have reported anti-microbial constituents of stingless bee (Tetragonula carbonaria) propolis from East Australia, but several components remained to be characterized. In the search of natural products yet unreported for Australian propolis, four bee deposit-resins of T. carbonaria bees were analysed by gas and liquid chromatography mass spectrometry with accurate mass measurements. Ethanolic extracts of the deposit-resins were tested in vitro against Staphylococcus aureus ATCC 25983 and Pseudomonas aeruginosa ATCC 27853 by the agar diffusion method. Phloroglucinols, flavonoids and isoprenoids were identified in samples. The crude extracts showed strong anti-staphylococcal effects but were less active against the Gram-negative bacterium. The diagnostic data enabled the identification of markers that can be used for profiling other Australian propolis sources and to target the isolation of bioactive phloroglucinols in future studies against antibiotic resistant S. aureus strains. Copyright © 2014 John Wiley & Sons, Ltd.

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.

Anti-quorum sensing activity of essential oils from Colombian plants.

Science.gov (United States)

Jaramillo-Colorado, Beatriz; Olivero-Verbel, Jesus; Stashenko, Elena E; Wagner-Döbler, Irene; Kunze, Brigitte

2012-01-01

Essential oils from Colombian plants were characterised by GC-MS, and assayed for anti-quorum sensing activity in bacteria sensor strains. Two major chemotypes were found for Lippia alba, the limonene-carvone and the citral (geranial-neral). For other species, the main components included α-pinene (Ocotea sp.), β-pinene (Swinglea glutinosa), cineol (Elettaria cardamomun), α-zingiberene (Zingiber officinale) and pulegone (Minthostachys mollis). Several essential oils presented promising inhibitory properties for the short chain AHL quorum sensing (QS) system, in Escherichia coli containing the biosensor plasmid pJBA132, in particular Lippia alba. Moderate activity as anti-QS using the same plasmid, were also found for selected constituents of essential oils studied here, such as citral, carvone and α-pinene, although solely at the highest tested concentration (250 µg mL(-1)). Only citral presented some activity for the long chain AHL QS system, in Pseudomonas putida containing the plasmid pRK-C12. In short, essential oils from Colombian flora have promising properties as QS modulators.

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

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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.

In ova angiogenesis analgesic and anti inflammatory potency of Aerva monsoniae (Amaranthaceae

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Sandhya S

2012-10-01

Full Text Available Objective: To evaluate the wound healing potency of aqueous extract of Aerva monsoniae (A. monsoniae by in vitro method using fertilized eggs, in vivo analgesic and anti inflammatory activity in rodents and the anti bacterial activity on the bacterial strains that infect the wound. Methods: The whole plant of A. monsoniae was extracted with water and then subjected to preliminary chemical screening. It was then evaluated for in ova angiogenesis on fertilized white leg horn eggs using the concentrations of 200-600 毺 g/mL. The analgesic activity was evaluated in mice using the dose 100 and 250 mg/kg. The anti inflammatory activity was evaluated in rats using the dose 250 mg/kg and 500 mg/kg. In both the parameters water was used as the control and diclofenac was used the standard. The anti bacterial activity on Staphylococcus aureus and Pseudomonas aerugenosa was performed. Results: The phytochemical screening revealed the presence of tannins, flavonoids and saponins. The in ova angiogenesis revealed a dose dependent activity which proves the wound healing claim of the plant as more number of blood capillaries were formed at the site of the drug. The plant proved to be a potent analgesic and anti inflammatory agent at doses 1 00 mg/kg and 250 mg/kg. The anti bacterial activity was present but at higher doses. Conclusions: The parameters studied in the present investigation proved that the plant is a potent wound healer. Further in vivo wound healing studies on animal model is desired. As the extract showed potent analgesic, anti inflammatory and anti bacterial properties, it can be considered that when formulated into suitable formulation, and it can reduce the pain, inflammation and infections related to wound very well.

A case of orbital apex syndrome due to Pseudomonas aeruginosa infection

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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 ...

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).

Determination of the spatiotemporal dependence of Pseudomonas aeruginosa biofilm viability after treatment with NLC-colistin

Directory of Open Access Journals (Sweden)

Sans-Serramitjana E

2017-06-01

Full Text Available Eulalia Sans-Serramitjana,1 Marta Jorba,1 José Luis Pedraz,2 Teresa Vinuesa,1 Miguel Viñas1 1Laboratory of Molecular Microbiology and Antimicrobials, Department of Pathology and Experimental Therapeutics, University of Barcelona, Barcelona, 2Laboratory of Pharmaceutics, University of the Basque Country (UPV/EHU, Centro de Investigación Biomédica en Red de Bioingeniería, Biomateriales y Nanomedicina, Vitoria, Spain Abstract: The emergence of colistin-resistant Pseudomonas aeruginosa in cystic fibrosis (CF patients, particularly after long-term inhalation treatments, has been recently reported. Nanoencapsulation may enable preparations to overcome the limitations of conventional pharmaceutical forms. We have determined the time-dependent viability of P. aeruginosa biofilms treated with both free and nanoencapsulated colistin. We also examined the relationship between the optimal anti-biofilm activity of nanostructured lipid carrier (NLC-colistin and the structural organization of the biofilm itself. The results showed the more rapid killing of P. aeruginosa bacterial biofilms by NLC-colistin than by free colistin. However, the two formulations did not differ in terms of the final percentages of living and dead cells, which were higher in the inner than in the outer layers of the treated biofilms. The effective anti-biofilm activity of NLC-colistin and its faster killing effect recommend further studies of its use over free colistin in the treatment of P. aeruginosa infections in CF patients. Keywords: cystic fibrosis, colistin sulfate, lipid nanoparticles, P. aeruginosa, confocal laser scanning microscopy, anti-biofilm activity

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

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, ...

CARACTERIZACIÓN DE IGYS ANTI-LECTINA DE Salvia bogotensis Y SU APLICACIÓN EN ESTUDIOS CITOQUÍMICOS PARA LA DETECCIÓN DEL ANTÍGENO TN

Directory of Open Access Journals (Sweden)

Nohora Vega

2010-02-01

Full Text Available Las inmunoglobulinas aisladas de la yema de huevo (IgY son muy utilizadas actualmente en diversos campos de las ciencias biológicas, dadas sus ventajas frente a las IgG séricas de mamíferos. En un trabajo previo establecimos las condiciones de obtención de IgY dirigidas contra la lectinas de Salvia bogotensis; su utilización en estudios inmunocitoquímicos requiere conocer sus principales características moleculares y las condiciones para la interacción IgY-lectina. La lectina de Salvia bogotensis (SBoL reconoce específicamente el antígeno Tn, marcador tumoral en muchos tipos de cáncer, pero se requieren herramientas adicionales para evidenciar esta interacción a nivel celular. Dada la disponibilidad de IgY anti-lectina de S. bogotensis, se realizó este trabajo con el objeto de caracterizar molecularmente estas IgY y evaluar su utilización en estudios inmunocitoquímicos para la detección del antígeno Tn en células tumorales. A las IgY purificadas se les determinó su punto isoeléctrico, peso molecular y contenido de carbohidratos. Para establecer la especificidad de interacción IgY-SBoL se obtuvieron lectinas homólogas y heterólogas y se ensayaron por ELLSA. La detección del antígeno Tn en las líneas celulares MCF-7 y HeLa con la lectina y las IgYs marcadas con biotina o peroxidasa se realizó por CELISA e inmunocitoquímica. Los resultados mostraron que los anticuerpos IgY anti-SBoL son una herramienta de una alta sensibilidad para los ensayos de reconocimiento específico del antígeno Tn.

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

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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

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...

Inhibition of biofilm development of uropathogens by curcumin - an anti-quorum sensing agent from Curcuma longa.

Science.gov (United States)

Packiavathy, Issac Abraham Sybiya Vasantha; Priya, Selvam; Pandian, Shunmugiah Karutha; Ravi, Arumugam Veera

2014-04-01

Urinary tract infection is caused primarily by the quorum sensing (QS)-dependent biofilm forming ability of uropathogens. In the present investigation, an anti-quorum sensing (anti-QS) agent curcumin from Curcuma longa (turmeric) was shown to inhibit the biofilm formation of uropathogens, such as Escherichia coli, Pseudomonas aeruginosa PAO1, Proteus mirabilis and Serratia marcescens, possibly by interfering with their QS systems. The antibiofilm potential of curcumin on uropathogens as well as its efficacy in disturbing the mature biofilms was examined under light microscope and confocal laser scanning microscope. The treatment with curcumin was also found to attenuate the QS-dependent factors, such as exopolysaccharide production, alginate production, swimming and swarming motility of uropathogens. Furthermore, it was documented that curcumin enhanced the susceptibility of a marker strain and uropathogens to conventional antibiotics. Copyright © 2012 Elsevier Ltd. All rights reserved.

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...

Evaluation of phytochemicals from medicinal plants of Myrtaceae family on virulence factor production by Pseudomonas aeruginosa.

Science.gov (United States)

Musthafa, Khadar Syed; Sianglum, Wipawadee; Saising, Jongkon; Lethongkam, Sakkarin; Voravuthikunchai, Supayang Piyawan

2017-05-01

Virulence factors regulated by quorum sensing (QS) play a critical role in the pathogenesis of an opportunistic human pathogen, Pseudomonas aeruginosa in causing infections to the host. Hence, in the present work, the anti-virulence potential of the medicinal plant extracts and their derived phytochemicals from Myrtaceae family was evaluated against P. aeruginosa. In the preliminary screening of the tested medicinal plant extracts, Syzygium jambos and Syzygium antisepticum demonstrated a maximum inhibition in QS-dependent violacein pigment production by Chromobacterium violaceum DMST 21761. These extracts demonstrated an inhibitory activity over a virulence factor, pyoverdin, production by P. aeruginosa ATCC 27853. Gas chromatography-mass spectrometric (GC-MS) analysis revealed the presence of 23 and 12 phytochemicals from the extracts of S. jambos and S. antisepticum respectively. Three top-ranking phytochemicals, including phytol, ethyl linoleate and methyl linolenate, selected on the basis of docking score in molecular docking studies lowered virulence factors such as pyoverdin production, protease and haemolytic activities of P. aeruginosa to a significant level. In addition, the phytochemicals reduced rhamnolipid production by the organism. The work demonstrated an importance of plant-derived compounds as anti-virulence drugs to conquer P. aeruginosa virulence towards the host. © 2017 APMIS. Published by John Wiley & Sons Ltd.

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)).

Natural isothiocyanates express antimicrobial activity against developing and mature biofilms of Pseudomonas aeruginosa.

Science.gov (United States)

Kaiser, Stefan J; Mutters, Nico T; Blessing, Brigitte; Günther, Frank

2017-06-01

The antimicrobial properties of natural isothiocyanates (ITCs) found in plants such as nasturtium (Tropaeolum majus) and horseradish (Armoracia rusticana), and the need of new chemotherapeutic options for treatment of infections caused by multidrug-resistant and biofilm-forming Gram-negative bacteria such as Pseudomonas aeruginosa (Pa), led us to evaluate the effects of three major ITCs, allylisothiocyanate (AITC), benzylisothiocyanate (BITC), and phenylethyl-isothiocyanate (PEITC), and a mixture (ITCM) adapted to the ITC composition after release of active components out of natural sources. Out of 105Pa isolates 27 isolates with increased biofilm formation were selected for testing. The effects of ITCs on Pa were evaluated regarding (1) planktonic bacterial proliferation, (2) biofilm formation, (3) metabolic activity in mature biofilms, and (4) synergism of ITCs and antibiotics. (1) Each ITC had anti-Pa activity. Mean minimum inhibitory concentrations (MICs) were (μg/ml, mean±standard deviation): AITC 103±6.9; BITC, 2145±249; PEITC 29,423±1652; and ITCM, 140±5. (2) Treating bacteria with PEITC and ITCM in concentrations below the MIC significantly inhibited biofilm formation. Particularly, ITCM reduced biofilm mass and bacterial proliferation. (3) ITCs significantly inhibited metabolic activity in mature biofilms. (4) Combining ITCs with meropenem synergistically increased antimicrobial efficacy on Pa biofilms. ITCs represent a promising group of natural anti-infective compounds with activity against Pa biofilms. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Anti-biofouling function of amorphous nano-Ta2O5 coating for VO2-based intelligent windows

Science.gov (United States)

Li, Jinhua; Guo, Geyong; Wang, Jiaxing; Zhou, Huaijuan; Shen, Hao; Yeung, Kelvin W. K.

2017-04-01

From environmental and health perspectives, the acquisition of a surface anti-biofouling property holds important significance for the usability of VO2 intelligent windows. Herein, we firstly deposited amorphous Ta2O5 nanoparticles on VO2 film by the magnetron sputtering method. It was found that the amorphous nano-Ta2O5 coating possessed a favorable anti-biofouling capability against Pseudomonas aeruginosa as an environmental microorganism model, behind which lay the mechanism that the amorphous nano-Ta2O5 could interrupt the microbial membrane electron transport chain and significantly elevate the intracellular reactive oxygen species (ROS) level. A plausible relationship was established between the anti-biofouling activity and physicochemical nature of amorphous Ta2O5 nanoparticles from the perspective of defect chemistry. ROS-induced oxidative damage gave rise to microbial viability loss. In addition, the amorphous nano-Ta2O5 coating can endow VO2 with favorable cytocompatibility with human skin fibroblasts. This study may provide new insights into understanding the anti-biofouling and antimicrobial actions of amorphous transition metal oxide nanoparticles, which is conducive to expanding their potential applications in environmental fields.

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...

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

Royal Jelly Inhibits Pseudomonas aeruginosa Adherence and Reduces Excessive Inflammatory Responses in Human Epithelial Cells

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Heni Susilowati

2017-01-01

Full Text Available Pseudomonas aeruginosa is a Gram-negative bacterium and causes respiratory infection especially in elderly patients. Royal jelly has been used worldwide as a traditional remedy and as a nutrient; however, the effect against P. aeruginosa is unclear. The aim of this study was to analyze antibacterial, antiadherent, and anti-inflammatory effects of royal jelly against P. aeruginosa. Wild-type strain PAO1 and clinical isolates of P. aeruginosa were used for antibacterial assay and antiadherent assay to abiotic surface and epithelial cells, which are pharynx (Detroit 562 and lung (NCI-H292 epithelial cells. In anti-inflammatory assay, epithelial cells were pretreated with royal jelly before bacterial exposure to investigate its inhibitory effect on interleukin (IL-8 and macrophage inflammatory protein-3α/CCL20 overproduction. Although royal jelly did not have antibacterial activity at concentration of 50% w/v, antiadherent activity was confirmed on the abiotic surface and epithelial cells under concentration of 25%. Pretreatment with royal jelly significantly inhibited overproduction of IL-8 and CCL20 from both cells. These results demonstrated that royal jelly inhibits P. aeruginosa adherence and protects epithelial cells from excessive inflammatory responses against P. aeruginosa infection. Our findings suggested that royal jelly may be a useful supplement as complementary and alternative medicine for preventing respiratory infection caused by P. aeruginosa.

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

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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

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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....

Anti-microbial principles of selected remedial plants from Southern India.

Science.gov (United States)

Tirupathi, Rao G; Suresh, Babu K; Ujwal, Kumar J; Sujana, P; Raoa, A Veerabhadr; Sreedhar, A S

2011-08-01

To examine the anti-bacterial activity of leaf extracts of Morus alba L. (Moraceae) and Piper betel L. (Piperaceae), and seed extracts of Bombax ceiba L. (Borabacaceae). We have partially purified plant extracts by solvent extraction method, and evaluated the effect of individual fractions on bacterial growth using Escherichia coli (E. coli), Pseudomonas aeruginosa (P. aeruginosa) and Staphylococcus aureus (S. aureus) bacterial strains. Compared with Morus and Bombax fractions, Piper fractions showed significant growth inhibition on all the three types of bacteria studied. The EtOAc-hexane fractions of Piper leaves exhibited significant anti-bacterial activity with minimum inhibitory concentrations (MIC) of 50 µg/mL culture against both gram-positive and gram-negative bacteria. The EtOAc-fractions I, II, and IV inhibited bacterial colony formation on soft agar in addition to growth inhibition. A combination treatment of piper fractions with ampicillin resulted in significant growth inhibition in E. coli and P. aeruginosa, and combination with anticancer drug geldanamycin (2µg/mL) showed selective growth inhibition against P. aeruginosa and S. aureus. Three major compounds, i.e., eugenol, 3-hexene-ol and stigmasterol, were primarily identified from Piper betel leaf extractions. Among the individual compounds, eugenol treatment showed improved growth inhibition compared with stigmasterol and 3-hexene-ol. We are reporting potential anti-bacterial compounds from Piper betel against both gram-positive and gram-negative bacteria either alone or in combination with drug treatment.

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.

Anti-bacteria activity of carbon nanotubes grown on trimetallic catalyst

Science.gov (United States)

Ibrahim, S. O.; Abdulkareem, A. S.; Isah, K. U.; Ahmadu, U.; Bankole, M. T.; Kariim, I.

2018-06-01

Trimetallic catalyst was prepared using wet impregnation method to produce carbon nanotubes (CNTs) through the method of catalytic chemical vapor deposition (CCVD). Characterization of the developed catalyst and CNTs were carried out using thermogravimetric analysis (TGA), x-ray diffraction (XRD), specific surface area Brunauer-Emmett-Teller (BET), Fourier-transform infrared spectroscopy (FTIR), high-resolution scanning electron microscopy (HRSEM)/energy dispersive x-ray spectroscopy (EDS) and high-resolution transmission electron microscopy (HRTEM)/selected area electron diffraction (SAED). The BET and TGA analysis indicated that the catalyst has a high surface area and is thermally stable. The FTIR of the developed catalyst shows notable functional group with presence of unbound water. The HRSEM of the catalyst revealed agglomerated, homogeneous and porous particles while the HRSEM/HRTEM of the produced CNTs gave the formation of long strand of multiwalled carbon nanotubes (MWCNTs), and homogeneous crystalline fringe like structure with irregular diameter. EDS revealed the dominance of carbon in the elemental composition. XRD/SAED patterns of the catalyst suggest high dispersion of the metallic particles in the catalyst mixture while that of the CNTs confirmed that the produced MWCNTs were highly graphitized and crystalline in nature with little structural defects. The anti-bacteria activity of the produced MWCNTs on Klebsiella pneumoneae, Escherichia coli, and Pseudomonas aeruginosa was also carried out. It was observed that the produced MWCNTs have an inhibitory property on bacteria; Escherichia coli and Klebsiella pneumoneae from zero day ( and ) through to twelfth day (Nil count) respectively. It has no effect on Pseudomonas aeruginosa with too numerous to count at zero-sixth day, but a breakdown in its growth at ninth-twelfth day (). This study implied that MWCNTs with varying diameter and well-ordered nano-structure can be produced from catalyst via CCVD

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 ...

Flavonoids Suppress Pseudomonas aeruginosa Virulence through Allosteric Inhibition of Quorum-sensing Receptors*

Science.gov (United States)

Paczkowski, Jon E.; Mukherjee, Sampriti; McCready, Amelia R.; Cong, Jian-Ping; Aquino, Christopher J.; Kim, Hahn; Henke, Brad R.; Smith, Chari D.; Bassler, Bonnie L.

2017-01-01

Quorum sensing is a process of cell-cell communication that bacteria use to regulate collective behaviors. Quorum sensing depends on the production, detection, and group-wide response to extracellular signal molecules called autoinducers. In many bacterial species, quorum sensing controls virulence factor production. Thus, disrupting quorum sensing is considered a promising strategy to combat bacterial pathogenicity. Several members of a family of naturally produced plant metabolites called flavonoids inhibit Pseudomonas aeruginosa biofilm formation by an unknown mechanism. Here, we explore this family of molecules further, and we demonstrate that flavonoids specifically inhibit quorum sensing via antagonism of the autoinducer-binding receptors, LasR and RhlR. Structure-activity relationship analyses demonstrate that the presence of two hydroxyl moieties in the flavone A-ring backbone are essential for potent inhibition of LasR/RhlR. Biochemical analyses reveal that the flavonoids function non-competitively to prevent LasR/RhlR DNA binding. Administration of the flavonoids to P. aeruginosa alters transcription of quorum sensing-controlled target promoters and suppresses virulence factor production, confirming their potential as anti-infectives that do not function by traditional bacteriocidal or bacteriostatic mechanisms. PMID:28119451

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

Antibacterial and anti-adhesion effects of the silver nanoparticles-loaded poly(L-lactide) fibrous membrane

International Nuclear Information System (INIS)

Liu, Shen; Zhao, Jingwen; Ruan, Hongjiang; Wang, Wei; Wu, Tianyi; Cui, Wenguo; Fan, Cunyi

2013-01-01

The complications of tendon injury are frequently compromised by peritendinous adhesions and tendon sheath infection. Physical barriers for anti-adhesion may increase the incidence of postoperative infection. This study was designed to evaluate the potential of silver nanoparticles (AgNPs)-loaded poly(L-lactide) (PLLA) electrospun fibrous membranes to prevent adhesion formation and infection. Results of an in vitro drug release study showed that a burst release was followed by sustained release from electrospun fibrous membranes with a high initial silver content. Fewer fibroblasts adhered to and proliferated on the AgNP-loaded PLLA electrospun fibrous membranes compared with pure PLLA electrospun fibrous membrane. In the antibacterial test, the AgNP-loaded PLLA electrospun fibrous membranes can prevent the adhesion of Gram-positive Staphylococcus aureus and Staphylococcus epidermidis and Gram-negative Pseudomonas aeruginosa. Taken together, these results demonstrate that AgNP-loaded PLLA electrospun fibrous membranes have the convenient practical medical potential of reduction of infection and adhesion formation after tendon injury. - Highlights: ► Silver nanoparticles are directly electrospun into PLLA fibrous membrane. ► Long-lasting release of Ag + ions is achieved. ► Cytotoxicity of silver ions benefits the anti-proliferation of physical barriers. ► Broad anti-microbial effect of drug-loaded fibrous membrane is revealed. ► Antibacterial and anti-adhesion effects of the physical barriers are combined

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.

Investigation of Pseudomonas aeruginosa quorum-sensing signaling system for identifying multiple inhibitors using molecular docking and structural analysis methodology.

Science.gov (United States)

Soheili, Vahid; Bazzaz, Bibi Sedigheh Fazly; Abdollahpour, Nooshin; Hadizadeh, Farzin

2015-12-01

Pseudomonas aeruginosa is an opportunistic human pathogen and a common Gram-negative bacterium in hospital-acquired infections. It causes death in many burn victims, cystic-fibrosis and neutropenic-cancer patients. It is known that P. aeruginosa biofilm maturation and production of cell-associated and extracellular virulence factors such as pyocyanin, elastase and rhamnolipids are under the control of a quorum-sensing (QS) system. Among several proteins involved in the Pseudomonas QS mechanism, LasR and PqsE play an important role in its cascade signaling system. They can cause increases in QS factors, biofilm maturation, and the production of virulence factors. Therefore, inhibition of these proteins can reduce the pathogenicity of P. aeruginosa. According to the structure of corresponding auto-inducers bound to these proteins, in silico calculations were performed with some non-steroidal anti-inflammatory drugs (NSAIDs) to estimate possible interactions and find the co-inhibitors of LasR and PqsE. The results showed that oxicams (Piroxicam and Meloxicam) can interact well with active sites of both proteins with the Ki of 119.43 nM and 4.0 μM for Meloxicam and 201.39 nM and 4.88 μM against LasR and PqsE, respectively. These findings suggested that Piroxicam and Meloxicam can be used as potential inhibitors for control of the P. aeruginosa QS signaling system and biofilm formation, and may be used in the design of multiple inhibitors. Copyright © 2015 Elsevier Ltd. All rights reserved.

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...

Glucocorticoids can affect Pseudomonas aeruginosa (ATCC 27853) internalization and intracellular calcium concentration in cystic fibrosis bronchial epithelial cells.

Science.gov (United States)

Hussain, Rashida; Shahror, Rami; Karpati, Ferenc; Roomans, Godfried M

2015-01-01

Glucocorticoids (GCs) are anti-inflammatory agents, but their use in cystic fibrosis (CF) is controversial. In CF, the early colonization with Pseudomonas aeruginosa is mainly due to nonmucoid strains that can internalize, and induce apoptosis in the epithelial cells. Uptake of P. aeruginosa by the epithelial cells and subsequent apoptosis may prevent colonization of P. aeruginosa in CF airways. In the airway epithelia, several other biological effects, including an anti-secretory role by decreasing intracellular Ca(2+) concentration have been described for this anti-inflammatory drug. However, the effects of GCs on the nonmucoid P. aeruginosa internalization and intracellular Ca(2+) in CF bronchial epithelial cells have not been evaluated. We used cultured human CF bronchial airway epithelial cell (CFBE) monolayers to determine P. aeruginosa internalization, apoptosis, and intracellular Ca(2+)concentration in CF bronchial epithelial cells. Cells were treated with IL-6, IL-8, dexamethasone, betamethasone, or budesonide. GCs in co-treatments with IL-6 reversed the effect of IL-6 by decreasing the internalization of P. aeruginosa in the CFBE cells. GCs decreased the extent of apoptosis in CFBE cells infected with internalized P. aeruginosa, and increased the intracellular Ca(2+) concentration. These findings suggest that if internalization of P. aeruginosa reduces infection, GC therapy would increase the risk of pulmonary infection by decreasing the internalization of P. aeruginosa in CF cells, but GCs may improve airway hydration by increasing the intracellular Ca(2+) concentration. Whether the benefits of GC treatment outweigh the negative effects is questionable, and further clinical studies need to be carried out.

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.

Bioprospecting Deep-Sea Actinobacteria for Novel Anti-infective Natural Products

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Dongbo Xu

2018-04-01

Full Text Available The global prevalence of drug resistance has created an urgent need for the discovery of novel anti-infective drugs. The major source of antibiotics in current clinical practice is terrestrial actinobacteria; the less-exploited deep-sea actinobacteria may serve as an unprecedented source of novel natural products. In this study, we evaluated 50 actinobacteria strains derived from diverse deep water sponges and environmental niches for their anti-microbial activities against a panel of pathogens including Candida albicans, Clostridium difficile, Staphylococcus aureus, and methicillin-resistant S. aureus (MRSA, and Pseudomonas aeruginosa. More than half of the tested strains (27 were identified as active in at least one assay. The rare earth salt lanthanum chloride (LaCl3 was shown to be as an effective elicitor. Among the 27 strains, the anti-microbial activity of 15 were induced or enhanced by the addition of LaCl3. This part of study focused on one strain R818, in which potent antifungal activity was induced by the addition of LaCl3. We found that the LaCl3-activated metabolites in R818 are likely antimycin-type compounds. One of them, compound 1, has been purified. Spectroscopic analyses including HR-MS and 1D NMR indicated that this compound is urauchimycin D. The antifungal activity of compound 1 was confirmed with a minimal inhibitory concentration (MIC of 25 μg/mL; the purified compound also showed a moderate activity against C. difficile. Additional notable strains are: strain N217 which showed both antifungal and antibacterial (including P. aeruginosa activities and strain M864 which showed potent activity against C. difficile with an MIC value (0.125 μg/mL lower than those of vancomycin and metronidazole. Our preliminary studies show that deep-sea actinobacteria is a promising source of anti-infective natural products.

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

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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

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...

The Diguanylate Cyclase HsbD Intersects with the HptB Regulatory Cascade to Control Pseudomonas aeruginosa Biofilm and Motility.

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Martina Valentini

2016-10-01

Full Text Available The molecular basis of second messenger signaling relies on an array of proteins that synthesize, degrade or bind the molecule to produce coherent functional outputs. Cyclic di-GMP (c-di-GMP has emerged as a eubacterial nucleotide second messenger regulating a plethora of key behaviors, like the transition from planktonic cells to biofilm communities. The striking multiplicity of c-di-GMP control modules and regulated cellular functions raised the question of signaling specificity. Are c-di-GMP signaling routes exclusively dependent on a central hub or can they be locally administrated? In this study, we show an example of how c-di-GMP signaling gains output specificity in Pseudomonas aeruginosa. We observed the occurrence in P. aeruginosa of a c-di-GMP synthase gene, hsbD, in the proximity of the hptB and flagellar genes cluster. We show that the HptB pathway controls biofilm formation and motility by involving both HsbD and the anti-anti-sigma factor HsbA. The rewiring of c-di-GMP signaling into the HptB cascade relies on the original interaction between HsbD and HsbA and on the control of HsbD dynamic localization at the cell poles.

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...

The anti-Phytophthora effect of selected potato-associated Pseudomonas strains: from the laboratory to the field

Directory of Open Access Journals (Sweden)

Anouk eGuyer

2015-11-01

Full Text Available Late blight, caused by the oomycete Phytophthora infestans, is the most devastating disease of potato. In organic farming, late Late blight, caused by the oomycete Phytophthora infestans, is the most devastating disease of potato. In organic farming, late blight is controlled by repeated applications of copper-based products, which negatively impact the environment. To find alternative solutions for late blight management, we have previously isolated a large collection of bacteria from the phyllosphere and the rhizosphere of potatoes. Here we report the antagonistic potential of these strains when co-cultivated with P. infestans as well as with other potato pathogens. We then focused on three Pseudomonas strains and compared their protective impact against late blight to that of well-known biocontrol strains in planta using a high-throughput leaf disc assay with automated picture analysis. When sprayed on the leaves of potatoes in the greenhouse, the strains were able to survive for at least 15 days. Under field conditions, populations decreased faster but all tested strains could still be retrieved after 8 days. The most active strain in vitro, P. chlororaphis R47, was also the best protectant on leaf discs from plants grown in the greenhouse experiment, but its protection potential could not be verified in the field due to unfavourable infection conditions. However, its protective effect against P. infestans in planta, its survival in the phyllosphere as well as its ability to colonise the potato rhizosphere in very high population densities, suggest a potential for field application, e.g. in the form of tuber treatment or leaf spray.

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...

Microbiological analysis of common preservatives used in food items and demonstration of their in vitro anti-bacterial activity

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Tohora Sultana

2014-12-01

Full Text Available Objective: To quantify the microorganisms contaminating the common preservatives used in food as well as to detect their in vitro anti-bacterial traits. Methods: A total of 9 preservatives were subjected to conventional cultural and biochemical methods for microbial enumeration. Anti-bacterial activities were demonstrated through the agar well diffusion method. Results: All samples were found to be contaminated with bacteria up to 105 CFU/g and with the fungal flora within a range of 1 01-1 02 CFU/g. Escherichia coli, Pseudomonas spp. and Staphylococcus spp. were demonstrated in most of the samples. Sodium sulfite and citric acid possessed the strongest anti-bacterial trait against all of the test bacteria. Acetic acid exhibited activity against 6 out of 8 test bacteria while vinegar exhibited the activity against 4 bacteria. Activity of salt was demonstrated only against Listeria spp. and Bacillus spp., while activity of sugar and honey was found only against Escherichia coli and Klebsiella spp., respectively. Conclusions: According to the current investigation, sodium sulfite and citric acid samples were found to be satisfactory preservatives both in terms of microbiological criteria and their antibacterial traits.

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

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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

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

Inhibitory effect of Thymus vulgaris and Origanum vulgare essential oils on virulence factors of phytopathogenic Pseudomonas syringae strains.

Science.gov (United States)

Carezzano, M E; Sotelo, J P; Primo, E; Reinoso, E B; Paletti Rovey, M F; Demo, M S; Giordano, W F; Oliva, M de Las M

2017-07-01

Pseudomonas syringae is a phytopathogenic bacterium that causes lesions in leaves during the colonisation process. The damage is associated with production of many virulence factors, such as biofilm and phytotoxins. The essential oils of Thymus vulgaris (thyme) and Origanum vulgare (oregano) have been demonstrated to inhibit P. syringae. The aim of this study was to investigate the effects of T. vulgaris and O. vulgare essential oils on production of virulence factors of phytopathogenic P. syringae strains, including anti-biofilm and anti-toxins activities. The broth microdilution method was used for determination of MIC and biofilm inhibition assays. Coronatine, syringomycin and tabtoxin were pheno- and genotypically evaluated. Both oils showed good inhibitory activity against P. syringae, with MIC values from 1.43 to 11.5 mg·ml -1 for thyme and 5.8 to 11.6 mg·ml -1 for oregano. Biofilm formation, production of coronatine, syringomycin and tabtoxin were inhibited by thyme and oregano essential oil in most strains. The results presented here are promising, demonstrating the bactericidal activity and reduction of virulence factor production after treatment with thyme and oregano oil, providing insight into how they exert their antibacterial activity. These natural products could be considered in the future for the control of diseases caused by P. syringae. © 2017 German Botanical Society and The Royal Botanical Society of the Netherlands.

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

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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.

Isolation, Phylogenetic Analysis and Anti-infective Activity Screening of Marine Sponge-Associated Actinomycetes

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Safwat Ahmed

2010-02-01

Full Text Available Terrestrial actinomycetes are noteworthy producers of a multitude of antibiotics, however the marine representatives are much less studied in this regard. In this study, 90 actinomycetes were isolated from 11 different species of marine sponges that had been collected from offshore Ras Mohamed (Egypt and from Rovinj (Croatia. Phylogenetic characterization of the isolates based on 16S rRNA gene sequencing supported their assignment to 18 different actinomycete genera representing seven different suborders. Fourteen putatively novel species were identified based on sequence similarity values below 98.2% to other strains in the NCBI database. A putative new genus related to Rubrobacter was isolated on M1 agar that had been amended with sponge extract, thus highlighting the need for innovative cultivation protocols. Testing for anti-infective activities was performed against clinically relevant, Gram-positive (Enterococcus faecalis, Staphylococcus aureus and Gram-negative (Escherichia coli, Pseudomonas aeruginosa bacteria, fungi (Candida albicans and human parasites (Leishmania major, Trypanosoma brucei. Bioactivities against these pathogens were documented for 10 actinomycete isolates. These results show a high diversity of actinomycetes associated with marine sponges as well as highlight their potential to produce anti-infective agents.

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

The LasB Elastase of Pseudomonas aeruginosa Acts in Concert with Alkaline Protease AprA To Prevent Flagellin-Mediated Immune Recognition.

Science.gov (United States)

Casilag, Fiordiligie; Lorenz, Anne; Krueger, Jonas; Klawonn, Frank; Weiss, Siegfried; Häussler, Susanne

2016-01-01

The opportunistic pathogen Pseudomonas aeruginosa is capable of establishing severe and persistent infections in various eukaryotic hosts. It encodes a wide array of virulence factors and employs several strategies to evade immune detection. In the present study, we screened the Harvard Medical School transposon mutant library of P. aeruginosa PA14 for bacterial factors that modulate interleukin-8 responses in A549 human airway epithelial cells. We found that in addition to the previously identified alkaline protease AprA, the elastase LasB is capable of degrading exogenous flagellin under calcium-replete conditions and prevents flagellin-mediated immune recognition. Our results indicate that the production of two proteases with anti-flagellin activity provides a failsafe mechanism for P. aeruginosa to ensure the maintenance of protease-dependent immune-modulating functions. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

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

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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

Selective inhibition of Erwinia amylovora by the herbicidally active germination-arrest factor (GAF) produced by Pseudomonas bacteria.

Science.gov (United States)

Halgren, A; Azevedo, M; Mills, D; Armstrong, D; Thimmaiah, M; McPhail, K; Banowetz, G

2011-10-01

 The germination-arrest factor (GAF) produced by Pseudomonas fluorescens WH6, and identified as 4-formylaminooxyvinylglycine, specifically inhibits the germination of a wide range of grassy weeds. This study was undertaken to determine whether GAF has antimicrobial activity in addition to its inhibitory effects on grass seed germination. Culture filtrate from Ps. fluorescens WH6 had little or no effect on 17 species of bacteria grown in Petri dish lawns, but the in vitro growth of Erwinia amylovora, the causal agent of the disease of orchard crops known as fire blight, was strongly inhibited by the filtrate. The anti-Erwinia activity of WH6 culture filtrate was shown to be due to its GAF content, and a commercially available oxyvinylglycine, 4-aminoethoxyvinylglycine (AVG), exhibited anti-Erwinia activity similar to that of GAF. The effects of GAF on Erwinia were reversed by particular amino acids. The biological properties of GAF include a rather specific antimicrobial activity against Erw. amylovora. This may be a general property of oxyvinylglycines as AVG exhibited similar activity. The ability of particular amino acids to reverse GAF inhibition is consistent with a potential effect of this compound on the activity of aminotransferases. The results presented here demonstrate a novel antimicrobial activity of oxyvinylglycines and suggest that GAF and/or GAF-producing bacteria may have potential for the control of fire blight. Journal of Applied Microbiology © 2011 The Society for Applied Microbiology. No claim to US Government works.

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

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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

Kinetic characterisation of arylamine N-acetyltransferase from Pseudomonas aeruginosa

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Sim Edith

2007-03-01

Full Text Available Abstract Background Arylamine N-acetyltransferases (NATs are important drug- and carcinogen-metabolising enzymes that catalyse the transfer of an acetyl group from a donor, such as acetyl coenzyme A, to an aromatic or heterocyclic amine, hydrazine, hydrazide or N-hydroxylamine acceptor substrate. NATs are found in eukaryotes and prokaryotes, and they may also have an endogenous function in addition to drug metabolism. For example, NAT from Mycobacterium tuberculosis has been proposed to have a role in cell wall lipid biosynthesis, and is therefore of interest as a potential drug target. To date there have been no studies investigating the kinetic mechanism of a bacterial NAT enzyme. Results We have determined that NAT from Pseudomonas aeruginosa, which has been described as a model for NAT from M. tuberculosis, follows a Ping Pong Bi Bi kinetic mechanism. We also describe substrate inhibition by 5-aminosalicylic acid, in which the substrate binds both to the free form of the enzyme and the acetyl coenzyme A-enzyme complex in non-productive reaction pathways. The true kinetic parameters for the NAT-catalysed acetylation of 5-aminosalicylic acid with acetyl coenzyme A as the co-factor have been established, validating earlier approximations. Conclusion This is the first reported study investigating the kinetic mechanism of a bacterial NAT enzyme. Additionally, the methods used herein can be applied to investigations of the interactions of NAT enzymes with new chemical entities which are NAT ligands. This is likely to be useful in the design of novel potential anti-tubercular agents.

Methanol Extract from Anogeissus leiocarpus (DC Guill. et Perr. (Combretaceae Stem Bark Quenches the Quorum Sensing of Pseudomonas aeruginosa PAO1

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Vincent Ouedraogo

2016-10-01

Full Text Available Background: Due to its extensive arsenal of virulence factors and inherent resistance to antibiotics, Pseudomonas aeruginosa is a threat particularly in immunocompromised patients. Considering the central role of quorum sensing in the production of virulence factors, inhibition of bacterial communication mechanism constitute an opportunity to attenuate pathogenicity of bacteria resistant to available antibiotics. Our study aimed to assess the anti-quorum sensing activity of Anogeissus leiocarpus, traditionally used in Burkina Faso, for the treatment of infected burn wounds. Methods: Investigations were carried out on methanol extract from A. leiocarpus stem bark. The reporter strains Chromobacterium violaceum CV026 and P. aeruginosa PAO1 derivatives were used to evidence any interference with the bacterial quorum sensing and expression of related genes. P. aeruginosa PAO1 was used to measure the impact on pyocyanin production. Results: At a sub-inhibitory concentration (100 µg/mL, A. leiocarpus methanol extract quenched the quorum sensing mechanism of P. aeruginosa PAO1 by down-streaming the rhlR gene, with a subsequent reduction of pyocyanin production. Moreover, the antioxidant polyphenols evidenced are able to reduce the oxidative stress induced by pyocyanin. Conclusion: The antioxidant and anti-quorum sensing activities of A. leiocarpus stem bark could justify its traditional use in the treatment of infected burn wounds.

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

Antibiotic resistant Pseudomonas spp. in the aquatic environment: A prevalence study under tropical and temperate climate conditions.

Science.gov (United States)

Devarajan, Naresh; Köhler, Thilo; Sivalingam, Periyasamy; van Delden, Christian; Mulaji, Crispin K; Mpiana, Pius T; Ibelings, Bastiaan W; Poté, John

2017-05-15

Microbial populations which are resistant to antibiotics are an emerging environmental concern with potentially serious implications for public health. Thus, there is a growing concern in exploring the occurrence of antibiotic resistance in the environment with no limitations to the factors that contribute to their emergence. The aquatic environment is considered to be a hot-spot for the acquisition and spread of antibiotic resistance due to pollution with emerging contaminants derived from anthropogenic activities. In this study, we report on the isolation and characterization of 141 Pseudomonas spp. from aquatic sediments receiving partially (un)treated hospital and communal effluents from three distinct geographical locations: Democratic Republic of the Congo (DRC), India (IN), and Switzerland (CH). P. putida (42%) and P. aeruginosa (39%) were the dominant Pseudomonas species. The highest frequency of antibiotic resistance against eight anti-pseudomonas agents was found among IN isolates (35-60%), followed by DRC (18-50%) and CH (12-54%). CTX-M was the most frequent β-lactamase found in CH (47% of isolates), while VIM-1 was dominant in isolates from DRC (61%) and IN (29%). NDM-1 was found in 29% of the total IN isolates and surprisingly also in 6% of CH isolates. Chromosomally-encoded efflux mechanisms were overexpressed in P. aeruginosa isolates from all three geographic locations. In vitro conjugative transfers of antibiotic resistance plasmids occurred more frequently under tropical temperatures (30 and 37 °C) than under temperate conditions (10 °C). The presence of Extended Spectrum β-lactamases (ESBLs) and Metallo β-lactamases (MBLs) in the isolates from environmental samples has important implications for humans who depend on public water supply and sanitation facilities. To our knowledge, this is the first study to demonstrate a comparison between treated/untreated effluents from urban and hospital settings as a source of microbial resistance

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

Chemical Characterization and Antioxidant, Antimicrobial, and Anti-Inflammatory Activities of South Brazilian Organic Propolis

Science.gov (United States)

Tiveron, Ana Paula; Rosalen, Pedro Luiz; Franchin, Marcelo; Lacerda, Risia Cristina Coelho; Bueno-Silva, Bruno; Benso, Bruna; Denny, Carina; Ikegaki, Masaharu; de Alencar, Severino Matias

2016-01-01

South Brazilian organic propolis (OP), which has never been studied before, was assessed and its chemical composition, scavenging potential of reactive oxygen species, antimicrobial and anti-inflammatory activities are herein presented. Based on the chemical profile obtained using HPLC, OP was grouped into seven variants (OP1–OP7) and all of them exhibited high scavenging activity, mainly against superoxide and hypochlorous acid species. OP1, OP2, and OP3 had the smallest minimal inhibitory concentration (MIC) against Gram-positive bacteria Streptococcus mutans, Streptococcus oralis, and Streptococcus aureus (12.5–100 μg/mL). OP1, OP2, OP3, and OP4 were more effective against Pseudomonas aeruginosa (Gram-negative), with MIC values ranging from 100 to 200 μg/mL. OP6 showed anti-inflammatory activity by decreasing NF-kB activation and TNF-α release in RAW 264.7 macrophages, and expressing the NF-κB-luciferase reporter stable gene. Therefore, south Brazilian OP can be considered an excellent source of bioactive compounds with great potential of application in the pharmaceutical and food industry. PMID:27802316

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.

Propolis-Sahara honeys preparation exhibits antibacterial and anti-biofilm activity against bacterial biofims formed on urinary catheters

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Saad Aissat

2016-11-01

Full Text Available Objective: To evaluate the antibacterial effect of Sahara honeys (SHs against bacterial biofilms formed on urinary catheters in combination with propolis-Sahara honeys (P-SHs. Methods: Three clinical isolates were subjected to biofilm detection methods. The antibacterial and anti-biofilm activity for SHs and P-SHs were determined using agar well diffusion and the percentage of biofilm inhibition (PBI methods. Results: The PBI for Gram-positive bacteria [Staphylococcus aureus (S. aureus] was in the range of 0%–20%, while PBI for Gram-negative bacteria [Pseudomonas aeruginosa and Escherichia coli (E. coli] were in range of 17%–57% and 16%–65%, respectively. The highest PBI (65% was produced by SH2 only on E. coli. In agar well diffusion assay, zones of inhibition ranged from 11–20 mm (S. aureus, 9–19 mm (Pseudomonas aeruginosa and 11–19 mm (E. coli. The highest inhibition (20 mm was produced by SH1 only on S. aureus. In addition, the treatment of SHs and P-SHs catheters with a polymicrobial biofilms reduced biofilm formation after 48 h exposure period. Conclussions: SHs and P-SHs applied as a natural agent can be used as a prophylactic agent to prevent the formation of in vitro biofilm.

Adhesion inhibition of F1C-fimbriated Escherichia coli and Pseudomonas aeruginosa PAK and PAO by multivalent carbohydrate ligands.

Science.gov (United States)

Autar, Reshma; Khan, A Salam; Schad, Matthias; Hacker, Jörg; Liskamp, Rob M J; Pieters, Roland J

2003-12-05

In order to evaluate their inhibition of bacterial adhesion, the carbohydrate sequences GalNAcbeta1-->4Gal and GalNAcbeta1-->4Galbeta1-->4Glc were synthesized. The disaccharide was conjugated to dendrons based on the 3,5-di-(2-aminoethoxy)-benzoic acid branching unit to yield di- and tetravalent versions of these compounds. A divalent compound was also prepared that had significantly longer spacer arms. Relevant monovalent compounds were prepared for comparison. Their anti-adhesion properties against F1C-fimbriated uropathogenic Escherichia coli were evaluated in an ELISA-type assay by using a recombinant strain and also by using Pseudomonas aeruginosa strains PAO and PAK. Adhesion inhibition was observed in all cases, and multivalency effects of up to one order of magnitude were observed. The combination of spacer and multivalency effects led to a 38-fold increase in the potency of a divalent inhibitor with long spacer arms towards the PAO strain when compared with the free carbohydrate.

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.

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.

Ellagic acid derivatives from Terminalia chebula Retz. downregulate the expression of quorum sensing genes to attenuate Pseudomonas aeruginosa PAO1 virulence.

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Sajal Sarabhai

Full Text Available BACKGROUND: Burgeoning antibiotic resistance in Pseudomonas aeruginosa has necessitated the development of anti pathogenic agents that can quench acylhomoserine lactone (AHL mediated QS with least risk of resistance. This study explores the anti quorum sensing potential of T. chebula Retz. and identification of probable compounds(s showing anti QS activity and the mechanism of attenuation of P. aeruginosa PAO1 virulence factors. METHODS AND RESULTS: Methanol extract of T. chebula Retz. fruit showed anti QS activity using Agrobacterium tumefaciens A136. Bioactive fraction (F7, obtained by fractionation of methanol extract using Sephadex LH20, showed significant reduction (p<0.001 in QS regulated production of extracellular virulence factors in P. aeruginosa PAO1. Biofilm formation and alginate were significantly (p<0.05 reduced with enhanced (20% susceptibility to tobramycin. Real Time PCR of F7 treated P. aeruginosa showed down regulation of autoinducer synthase (lasI and rhlI and their cognate receptor (lasR and rhlR genes by 89, 90, 90 and 93%, respectively. Electrospray Ionization Mass Spectrometry also showed 90 and 64% reduction in the production of 3-oxo-C(12HSL and C(4HSL after treatment. Decrease in AHLs as one of the mechanisms of quorum quenching by F7 was supported by the reversal of inhibited swarming motility in F7-treated P. aeruginosa PAO1 on addition of C(4HSL. F7 also showed antagonistic activity against 3-oxo-C(12HSL-dependent QS in E. coli bioreporter. C. elegans fed on F7-treated P. aeruginosa showed enhanced survival with LT50 increasing from 24 to 72 h. LC-ESI-MS of F7 revealed the presence of ellagic acid derivatives responsible for anti QS activity in T. chebula extract. CONCLUSIONS: This is the first report on anti QS activity of T. chebula fruit linked to EADs which down regulate the expression of lasIR and rhlIR genes with concomitant decrease in AHLs in P. aeruginosa PAO1 causing attenuation of its virulence factors

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...

Qingfei Xiaoyan Wan, a traditional Chinese medicine formula, ameliorates Pseudomonas aeruginosa–induced acute lung inflammation by regulation of PI3K/AKT and Ras/MAPK pathways

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Yuanyuan Hou

2016-05-01

Full Text Available Gram-negative pathogen–induced nosocomial infections and resistance are a most serious menace to global public health. Qingfei Xiaoyan Wan (QF, a traditional Chinese medicine (TCM formula, has been used clinically in China for the treatment of upper respiratory tract infections, acute or chronic bronchitis and pulmonary infection. In this study, the effects of QF on Pseudomonas aeruginosa–induced acute pneumonia in mice were evaluated. The mechanisms by which four typical anti-inflammatory ingredients from QF, arctigenin (ATG, cholic acid (CLA, chlorogenic acid (CGA and sinapic acid (SPA, regulate anti-inflammatory signaling pathways and related targets were investigated using molecular biology and molecular docking techniques. The results showed that pretreatment with QF significantly inhibits the release of cytokines (TNF-α and IL-6 and chemokines (IL-8 and RANTES, reduces leukocytes recruitment into inflamed tissues and ameliorates pulmonary edema and necrosis. In addition, ATG was identified as the primary anti-inflammatory agent with action on the PI3K/AKT and Ras/MAPK pathways. CLA and CGA enhanced the actions of ATG and exhibited synergistic NF-κB inactivation effects possibly via the Ras/MAPK signaling pathway. Moreover, CLA is speculated to target FGFR and MEK firstly. Overall, QF regulated the PI3K/AKT and Ras/MAPK pathways to inhibit pathogenic bacterial infections effectively.

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.

Aplicación del método inmunocitoquímico de la fosfatasa alcalina anti-fosfatasa alcalina para la clasificación inmunológica de las leucemias mieloides agudas Application of the alkaline phosphatase anti-alkaline phosphatase immunocytochemical method for the immunological classification of acute myeloid leukemias

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Bertha B Socarrás Ferrer

2006-04-01

Full Text Available Se realizó el inmunofenotipaje celular de 30 pacientes con el diagnóstico de leucemia mieloide aguda por el método inmunocitoquímico fosfatasa alcalina anti-fosfatasa alcalina (APAAP introducido en nuestro laboratorio. Los marcadores estudiados fueron: CD3, CD13, CD15, CD19, CD33 y CD41. Para el estudio se utilizaron extendidos de médula ósea o sangre periférica fijados en acetona pura e incubados con el respectivo anticuerpo monoclonal. Posteriormente se añadió la inmunoglobulina anti ratón obtenida en conejo ( Linking y por último, el complejo APAAP. Los períodos de incubación fueron de 30 minutos y se realizaron lavados con solución amortiguadora entre cada uno de los pasos. La lectura de las láminas se realizó en microscopio óptico y se consideró positivo cuando el número de células marcadas era mayor o igual a 20 %. De los pacientes estudiados, el 93,3 % y el 90 %, respectivamente, expresaron antígenos pan mieloides CD13 y CD33; 16 de ellos expresaron el CD15 (53,3 %; 3 el CD19 (10 % y 2 el CD41 (6,6 %. Se concluyó que el método APAAP es rápido y de bajo costo y puede ser aplicado con confiabilidad en la clasificación inmunológica de las leucemias mieloides agudasThe cellular immunophenotyping of 30 patients with the diagnosis of acute myeloid leukemia was conducted by the alkaline phosphatase anti-alkaline phosphatase immunocytochemical method (APAAP introduced in our laboratory. The markers studied were: CD3, CD13, CD15, CD19, CD33 y CD41. Specimens of bone marrow or peripheral blood fixed in pure acetone and incubated with the respective monoclonal antibody were used for the study. Later on, the anti-mouse immunoglobulin obtained in rabbit (Linking was added and, finally, the APAAP complex. The incubation periods were of 30 minutes and lavages with buffer solution were carried out between one step and the other. The reading of the slides was performed on the optical microscope and it was considered positive when

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.

Antimicrobial activity of synthetic cationic peptides and lipopeptides derived from human lactoferricin against Pseudomonas aeruginosa planktonic cultures and biofilms.

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Sánchez-Gómez, Susana; Ferrer-Espada, Raquel; Stewart, Philip S; Pitts, Betsey; Lohner, Karl; Martínez de Tejada, Guillermo

2015-07-07

Infections by Pseudomonas aeruginosa constitute a serious health threat because this pathogen -particularly when it forms biofilms - can acquire resistance to the majority of conventional antibiotics. This study evaluated the antimicrobial activity of synthetic peptides based on LF11, an 11-mer peptide derived from human lactoferricin against P. aeruginosa planktonic and biofilm-forming cells. We included in this analysis selected N-acylated derivatives of the peptides to analyze the effect of acylation in antimicrobial activity. To assess the efficacy of compounds against planktonic bacteria, microdilution assays to determine the minimal inhibitory concentration (MIC), minimum bactericidal concentration (MBC) and time-kill studies were conducted. The anti-biofilm activity of the agents was assessed on biofilms grown under static (on microplates) and dynamic (in a CDC-reactor) flow regimes. The antimicrobial activity of lipopeptides differed from that of non-acylated peptides in their killing mechanisms on planktonic and biofilm-forming cells. Thus, acylation enhanced the bactericidal activity of the parental peptides and resulted in lipopeptides that were uniformly bactericidal at their MIC. In contrast, acylation of the most potent anti-biofilm peptides resulted in compounds with lower anti-biofilm activity. Both peptides and lipopeptides displayed very rapid killing kinetics and all of them required less than 21 min to reduce 1,000 times the viability of planktonic cells when tested at 2 times their MBC. The peptides, LF11-215 (FWRIRIRR) and LF11-227 (FWRRFWRR), displayed the most potent anti-biofilm activity causing a 10,000 fold reduction in cell viability after 1 h of treatment at 10 times their MIC. At that concentration, these two compounds exhibited low citotoxicity on human cells. In addition to its bactericidal activity, LF11-227 removed more that 50 % of the biofilm mass in independent assays. Peptide LF11-215 and two of the shortest and least

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

[Analytic study of dot blotting for the detection of anti-Jo-1, anti-M2, anti-ribosomes and anti-LKM].

Science.gov (United States)

Huguet, S; Sghiri, R; Ballot, E; Johanet, C

2004-01-01

The Cyto-Dot 4 HM043 kit commercialised by BMD, has replaced the Cyto-Dot HM010 kit that allowed three auto-antibodies detection (anti-Jo-1, anti-M2 and anti-ribosomal protein). Detection of anti-LKM1 auto-antibody was added. These four auto-antibodies have in common only the intracytoplasmic localisation of their respective antigen. The aim of our study was to evaluate this new kit using 104 sera and to compare our results with reference techniques (indirect immunofluorescence IF for anti-M2, anti-ribosomal protein and anti-LKM1, double immunodiffusion ID for anti-Jo-1 and anti-LKM1, western blotting WB for anti-M2) and with Cyto-Dot HM010. The one hundred and four sera were divided into five groups: Group I (n = 12) with anti-Jo-1 detected by ID; Group II (n = 28) with 26 anti-M2 positive by IF and WB, 2 anti-M2 positive only by WB; Group III (n = 10) with anti-ribosomal protein detected by IF 5 of which precipitated by ID; Group IV (n = 32) with anti-LKM1 by IF and ID divided into 18 AIH2 and 14 HCV; Group V (n = 22) consisting of 14 healthy individuals and 8 patients with hypergammaglobulinemia. Results of this study are similar to those of Cyto-Dot HM010 for the three auto-antibodies already in use. Cyto-Dot 4 is a very good anti-LKM1 confirmation method as it is ID. Copyright John Libbey Eurotext 2003.

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

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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

Directory of Open Access Journals (Sweden)

Vladimír Vietoris

2012-02-01

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

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...

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

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.)

Fabrication and characterization of functionalized surfaces with 3-amino propyltrimethoxysilane films for anti-infective therapy applications

Energy Technology Data Exchange (ETDEWEB)

Grumezescu, Valentina [Department of Science and Engineering of Oxide Materials and Nanomaterials, Faculty of Applied Chemistry and Materials Science, University Politehnica of Bucharest, 1–7 Polizu Street, 011061 Bucharest (Romania); Lasers Department, National Institute for Lasers, Plasma & Radiation Physics, P.O. Box MG-36, Magurele, Bucharest (Romania); Andronescu, Ecaterina [Lasers Department, National Institute for Lasers, Plasma & Radiation Physics, P.O. Box MG-36, Magurele, Bucharest (Romania); Holban, Alina Maria [Department of Science and Engineering of Oxide Materials and Nanomaterials, Faculty of Applied Chemistry and Materials Science, University Politehnica of Bucharest, 1–7 Polizu Street, 011061 Bucharest (Romania); Microbiology Immunology Department, Faculty of Biology, Research Institute of the University of Bucharest – ICUB, University of Bucharest, 1–3 Portocalelor Lane, Sector 5, 77206 Bucharest (Romania); Socol, Gabriel [Lasers Department, National Institute for Lasers, Plasma & Radiation Physics, P.O. Box MG-36, Magurele, Bucharest (Romania); Grumezescu, Alexandru Mihai, E-mail: grumezescu@yahoo.com [Department of Science and Engineering of Oxide Materials and Nanomaterials, Faculty of Applied Chemistry and Materials Science, University Politehnica of Bucharest, 1–7 Polizu Street, 011061 Bucharest (Romania); Ficai, Anton [Department of Science and Engineering of Oxide Materials and Nanomaterials, Faculty of Applied Chemistry and Materials Science, University Politehnica of Bucharest, 1–7 Polizu Street, 011061 Bucharest (Romania); Lazar, Veronica; Chifiriuc, Mariana Carmen [Microbiology Immunology Department, Faculty of Biology, Research Institute of the University of Bucharest – ICUB, University of Bucharest, 1–3 Portocalelor Lane, Sector 5, 77206 Bucharest (Romania); Trusca, Roxana [S.C Metav-CD S.A., 31 Rosetti Str., 020015 Bucharest (Romania); and others

2015-05-01

Graphical abstract: - Highlights: • Thin coatings based on 3-amino propyltrimethoxysilane with anti-adherent properties. • PVC modified surfaces with improved resistance to microbial colonization. • Firstly report on antimicrobial properties of 3-amino propyltrimethoxysilane. - Abstract: The purpose of this study was the fabrication of functionalized anti-adherent surfaces based on the polyvinyl chloride (PVC) coated with 3-amino propyltrimethoxysilane (APTMS) by matrix assisted pulsed laser evaporation (MAPLE) in order to improve the resistance of PVC based prosthetic devices to microbial colonization. Infrared microscopy (IRM) investigations of APTMS thin films proved the compositional homogeneity of the prepared thin film. Scanning electron microscopy (SEM) micrographs revealed a granular morphology with microspheres harboring a diameter between 15 and 60 nm. The microbiological assays proved that MAPLE deposited APTMS films inhibited the adherence capacity and biofilm development of Pseudomonas aeruginosa and Staphylococcus aureus strains. Furthermore, this material proved to be highly biocompatible, allowing the normal growth and development of human endothelial cells. These traits highlight the fact that the fabricated APTMS thin films may be efficiently used for improving different surfaces of medical use, including prostheses and implantable devices.

Fabrication and characterization of functionalized surfaces with 3-amino propyltrimethoxysilane films for anti-infective therapy applications

International Nuclear Information System (INIS)

Grumezescu, Valentina; Andronescu, Ecaterina; Holban, Alina Maria; Socol, Gabriel; Grumezescu, Alexandru Mihai; Ficai, Anton; Lazar, Veronica; Chifiriuc, Mariana Carmen; Trusca, Roxana

2015-01-01

Graphical abstract: - Highlights: • Thin coatings based on 3-amino propyltrimethoxysilane with anti-adherent properties. • PVC modified surfaces with improved resistance to microbial colonization. • Firstly report on antimicrobial properties of 3-amino propyltrimethoxysilane. - Abstract: The purpose of this study was the fabrication of functionalized anti-adherent surfaces based on the polyvinyl chloride (PVC) coated with 3-amino propyltrimethoxysilane (APTMS) by matrix assisted pulsed laser evaporation (MAPLE) in order to improve the resistance of PVC based prosthetic devices to microbial colonization. Infrared microscopy (IRM) investigations of APTMS thin films proved the compositional homogeneity of the prepared thin film. Scanning electron microscopy (SEM) micrographs revealed a granular morphology with microspheres harboring a diameter between 15 and 60 nm. The microbiological assays proved that MAPLE deposited APTMS films inhibited the adherence capacity and biofilm development of Pseudomonas aeruginosa and Staphylococcus aureus strains. Furthermore, this material proved to be highly biocompatible, allowing the normal growth and development of human endothelial cells. These traits highlight the fact that the fabricated APTMS thin films may be efficiently used for improving different surfaces of medical use, including prostheses and implantable devices

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

Directory of Open Access Journals (Sweden)

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.

Anti-G with concomitant anti-C and anti-D: A case report in a pregnant woman.

Science.gov (United States)

Yousuf, Rabeya; Mustafa, Ahmad Nasirudin; Ho, Siew-Ling; Tang, Yee-Loong; Leong, Chooi-Fun

2017-01-01

The G antigen of Rh blood group system is present in almost all D-positive or C-positive red cells but absent from red cells lacking D and C antigens. The differentiation of anti-D and anti-C from anti-G is not necessary for routine transfusion; however, during pregnancy, it is important because anti-G can masquerade as anti-D and anti-C with initial antibody testing. The false presence of anti-D will exclude the patient from receiving anti-D immunoglobulin (RhIG) when the patient actually is a candidate for RhIG prophylaxis. Moreover, patients with positive anti-D or anti-G are at risk of developing hemolytic disease of the fetus and newborn and need close monitoring. Thus, proper identification allows the clinicians to manage patients properly. This case report highlights a rare case of anti-G together with anti-D and anti-C in a pregnant woman. This report disseminates knowledge on identification of anti-G and its importance in pregnant women.

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

Anti-Cyclic Citrullinated Peptide (Anti-CCP and Anti-Mutated Citrullinated Vimentin (Anti-MCV Relation with Extra-Articular Manifestations in Rheumatoid Arthritis

Directory of Open Access Journals (Sweden)

Laura Gonzalez-Lopez

2014-01-01

Full Text Available We evaluated the association between anti-cyclic citrullinated peptide antibodies (anti-CCP and anti-mutated citrullinated vimentin antibodies (anti-MCV with the presence of extra-articular (ExRA manifestations in 225 patients with rheumatoid arthritis (RA. Ninety-five patients had ExRA and 130 had no ExRA. There was no association of anti-CCP and anti-MCV levels with the presence of ExRA as total group (P=0.40 and P=0.91, resp.. Making an analysis of individual manifestations, rheumatoid nodules were associated with positivity for rheumatoid factor (RF; (P=0.01, anti-CCP (P=0.048, and anti-MCV (P=0.02. Instead, RF, anti-CCP, or anti-MCV were not associated with SS, chronic anemia, or peripheral neuropathy. Levels of anti-CCP correlated with the score of the Health Assessment Questionnaire-Disability Index (HAQ-Di (r=0.154, P=0.03, erythrocyte sedimentation rate (ESR; (r=0.155, P=0.03, and RF (P=0.254, P<0.001, whereas anti-MCV titres only correlated with RF (r=0.169, P=0.02. On adjusted analysis, ExRA was associated with longer age (P=0.015, longer disease duration (P=0.007, higher DAS-28 score (P=0.002, and higher HAQ-DI score (P=0.007, but serum levels of anti-CCP and anti-MCV were not associated. These findings show the need to strengthen the evaluation of the pathogenic mechanisms implied in each specific ExRA manifestation.

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

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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.

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.

Anti-G with concomitant anti-C and anti-D: A case report in a pregnant woman

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Rabeya Yousuf

2017-01-01

Full Text Available The G antigen of Rh blood group system is present in almost all D-positive or C-positive red cells but absent from red cells lacking D and C antigens. The differentiation of anti-D and anti-C from anti-G is not necessary for routine transfusion; however, during pregnancy, it is important because anti-G can masquerade as anti-D and anti-C with initial antibody testing. The false presence of anti-D will exclude the patient from receiving anti-D immunoglobulin (RhIG when the patient actually is a candidate for RhIG prophylaxis. Moreover, patients with positive anti-D or anti-G are at risk of developing hemolytic disease of the fetus and newborn and need close monitoring. Thus, proper identification allows the clinicians to manage patients properly. This case report highlights a rare case of anti-G together with anti-D and anti-C in a pregnant woman. This report disseminates knowledge on identification of anti-G and its importance in pregnant women.

Biotransformation of isoeugenol to vanillin by Pseudomonas putida IE27 cells.

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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.

Anti-bacterial Efficacy of Bacteriocin Produced by Marine Bacillus subtilis Against Clinically Important Extended Spectrum Beta-Lactamase Strains and Methicillin-Resistant Staphylococcus aureus

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Suresh Mickymaray

2018-02-01

Full Text Available Objective: To investigate the anti-bacterial efficacy of bacteriocin produced by Bacillus subtilis SM01 (GenBank accession no: KY612347, a Gram-positive marine bacterium, against Extended Spectrum Beta-Lactamase (ESBL producing Gram-negative pathogens Acinetobacter baumannii, Pseudomonas aeruginosa, and Escherichia coli, and Gram-positive pathogen Methicillin-Resistant Staphylococcus aureus (MRSA. Methods: A marine bacterium was isolated from mangrove sediment from the Red Sea coast of Jeddah, Kingdom of Saudi Arabia, and identified based on its morphological, biochemical, and molecular characteristics. The bacteriocin production using this isolate was carried out in brain heart infusion broth (BHIB medium. The Anti-bacterial activity of bacteriocin was evaluated against selected ESBL strains and MRSA by the well agar method. The effects of incubation time, pH, and temperature on the Anti-bacterial activity were studied. Results: The bacteriocin Bac-SM01 produced by B. subtilis SM01 demonstrated broad-spectrum Anti-bacterial activity against both Gram-negative and -positive bacteria. The present study is the first report that the bacteriocin Bac-SM01 inhibits the growth of ESBL producing Gram-negative strains A. baumannii, P. aeruginosa, and E. coli, and a Gram-positive MRSA strain. The optimum incubation time, pH, and temperature for the Anti-bacterial activity of Bac-SM01 was 24 h, 7, and 37°C respectively. Conclusion: The overall investigation can conclude that the bacteriocin Bac-SM01 from the marine isolate Bacillus subtilis SM01 could be used as an alternative Anti-bacterial agent in pharmaceutical products.

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

Respuesta neuroinmunológica en la encefalitis asociada al virus del dengue

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Bárbara Padilla-Docal

2013-12-01

Full Text Available El virus del dengue es un virus ARN miembro de la familia Flaviviridae, la cual incluye, además, el de la fiebre amarilla, el del Nilo del Oeste y la encefalitis japonesa. Se realizó un estudio retrospectivo con tres pacientes diagnosticados de encefalitis asociada al dengue, en cuyas muestras de suero y líquido cefalorraquídeo se cuantificaron los niveles de las clases mayores de inmunoglobulinas por inmunodifusión radial y la manosa de unión a lectina, proteína de la vía de las lectinas del sistema del complemento por fluorometría. En el reibergrama se muestra la presencia de síntesis intratecal de las tres clases de inmunoglobulinas y ausencia de síntesis intratecal de lectina de unión a manosa. Existieron diferencias en cuanto al por ciento de síntesis intratecal de inmunoglobulinas, las cuales estuvieron relacionadas con el momento de la infección por el virus y la aparición de las manifestaciones neurológicas compatibles con una encefalitis. Este es el primer reporte de afectaciones neurológicas en pacientes cubanos con dengue. La respuesta inmune intratecal puede ser utilizada para el mejor conocimiento de la enfermedad y contribuir al desarrollo de posibles candidatos vacunales.

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

Science.gov (United States)

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

2016-01-01

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

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.

Model independent calculation of B(anti B0→D(*)+τ- anti ν)/B(anti B0→D(*)+e- anti ν)

International Nuclear Information System (INIS)

Hwang, D.S.

2000-01-01

Using the formulas for the dΓ/dq 2 distribution with non-zero lepton mass and experimentally determined form factors, we calculate the dΓ(D (*)+ l - anti ν)/dq 2 spectra and branching fractions for l=e,μ and τ. We obtain the results B(anti B 0 →D + τ - anti ν)/B(anti B 0 →D + e - anti ν)=0.278 +0.049 -0.035 and B(anti B 0 →D *+ τ - anti ν)/B(anti B 0 →D *+ e - anti ν)=0.256 +0.014 -0.013 . Since we used the experimentally measured form factors, these results are independent of theoretical models of the form factors. (orig.)

Advances toward the elucidation of hypertonic saline effects on Pseudomonas aeruginosa from cystic fibrosis patients.

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Anne-Laure Michon

Full Text Available OBJECTIVES: Nebulized hypertonic saline (HTS has beneficial effects including reducing pulmonary exacerbations in Cystic Fibrosis (CF patients. Several mechanisms may explain these effects but antimicrobial activity of NaCl remains largely unexplored. We aimed to measure the antimicrobial effect of NaCl on Pseudomonas aeruginosa isolated from the respiratory tract in CF patients. METHODS: NaCl minimal inhibitory concentration (MIC and minimal bactericidal concentration (MBC were determined for strains characterized for mucoidy, antimicrobial resistance, and ability to form biofilm using 0,9% to 15% NaCl solutions. NaCl effects on biofilm formation, preformed biofilm, and mobility were evaluated. Kinetics of antimicrobial effects was studied. RESULTS: The growth of all isolates (n = 85 from 34 patients was inhibited by 6% NaCl solution. A 10% concentration had a bactericidal activity on 90% of the isolates. Mucoid and multidrug resistant (MDR isolates displayed lower MICs compared to non-mucoid and to non-MDR isolates, respectively. Time-kill kinetics showed that NaCl exhibited a rapid, dose and growth phase dependent bactericidal effect. Three percent or more of NaCl inhibited biofilm formation for 69% of strongly adherent isolates. A dose-dependent decrease of preformed biofilm viability and an inhibitory activity on bacterial motility were observed. CONCLUSIONS: NaCl inhibited the growth of all isolates and killed 38% of tested isolates within concentration range currently used in therapeutics. Our results suggest that anti-pseudomonal activity is another mechanism of action of HTS to add to those already established. Clinical trials are needed to compare diverse HTS conditions of use (rhythm, dose and mode of delivery to obtain efficient and optimized anti-P. aeruginosa effects. More generally, NaCl effect on other opportunistic pathogens as well as on global microbiotae recovered during polymicrobial diseases warrants further investigations.

A Marine Actinomycete Rescues Caenorhabditis elegans from Pseudomonas aeruginosa Infection through Restitution of Lysozyme 7

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Siti N. Fatin

2017-11-01

Full Text Available The resistance of Pseudomonas aeruginosa to conventional antimicrobial treatment is a major scourge in healthcare. Therefore, it is crucial that novel potent anti-infectives are discovered. The aim of the present study is to screen marine actinomycetes for chemical entities capable of overcoming P. aeruginosa infection through mechanisms involving anti-virulence or host immunity activities. A total of 18 actinomycetes isolates were sampled from marine sediment of Songsong Island, Kedah, Malaysia. Upon confirming that the methanolic crude extract of these isolates do not display direct bactericidal activities, they were tested for capacity to rescue Caenorhabditis elegans infected with P. aeruginosa strain PA14. A hexane partition of the extract from one isolate, designated as Streptomyces sp. CCB-PSK207, could promote the survival of PA14 infected worms by more than 60%. Partial 16S sequence analysis on this isolate showed identity of 99.79% with Streptomyces sundarbansensis. This partition did not impair feeding behavior of C. elegans worms. Tested on PA14, the partition also did not affect bacterial growth or its ability to colonize host gut. The production of biofilm, protease, and pyocyanin in PA14 were uninterrupted, although there was an increase in elastase production. In lys-7::GFP worms, this partition was shown to induce the expression of lysozyme 7, an important innate immunity defense molecule that was repressed during PA14 infection. GC-MS analysis of the bioactive fraction of Streptomyces sp. CCB-PSK207 revealed the presence of methyl esters of branched saturated fatty acids. In conclusion, this is the first report of a marine actinomycete producing metabolites capable of rescuing C. elegans from PA14 through a lys-7 mediated activity.

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

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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.

What is it really? Anti-G or Anti-D plus Anti-C: Clinical Significance in Antenatal Mothers.

Science.gov (United States)

Das, Soumya; Shastry, Shamee; Murugesan, M; B, Poornima Baliga; Shastry, Shamee

2017-06-01

G antigen of Rh blood group system is present either along with D and/or C positive red cells. Hence, [serologically anti-G presents with the similar picture as that of multiple antibodies (anti-D + anti-C). Differentiating them is important as anti-D + anti-C causes severe hemolytic disease of the fetus and newborn than anti-G. In pregnancies with anti-G alone, alloimmunization due to D antigen could be prevented by prophylactic administration of RhIg. Differentiating between anti-D + C from anti-G in alloimmunized pregnant mothers becomes essential. Sera from antenatal mothers, whose antibody identification by 11-cell panel gave a pattern for anti-D and anti-C were selected. Extended phenotyping for Rh system was performed for these antenatal cases. Differential adsorption and elution testing using R 2 R 2 cells initially and r'r cells subsequently were performed to distinguish anit-G from anti-D + anti-C. Antibody titers of these antibodies were determined and their clinical outcome in the newborn was followed. A pattern suggestive of anti D and anti C on antibody identification were observed in six antenatal cases. On further workup 50 % of them confirmed to have anti G. Antibody titers of anti-G and anti-C were lower than that of Anti-D. All newborns were sensitized in vivo and the antibody specificity in them were confirmed with elution studies. The mothers who had only anti-G were subsequently administered with an appropriate dose of RhIg.Differential adsorption and elution studies help in identifying anti-G and distinguishing it from anti-D plus anti-C, thus helping in better patient management.

Mechanism of action and in vitro activity of short hybrid antimicrobial peptide PV3 against Pseudomonas aeruginosa

International Nuclear Information System (INIS)

Memariani, Hamed; Shahbazzadeh, Delavar; Sabatier, Jean-Marc; Memariani, Mojtaba; Karbalaeimahdi, Ali; Bagheri, Kamran Pooshang

2016-01-01

Antimicrobial peptides are attractive candidates for developing novel therapeutic agents, since they are lethal to a broad spectrum of pathogens and have a unique low tendency for resistance development. In this study, mechanism of action and in vitro anti-pseudomonal activity of previously designed short hybrid antimicrobial peptide PV3 were investigated. Compared to ceftazidime, PV3 had not only higher antibacterial activity but also faster bactericidal activity. PV3 reduced biofilm biomass and viability of biofilm embedded bacteria in a concentration-dependent manner. Although the antimicrobial activity of PV3 was reduced in Mueller-Hinton broth (MHB) containing human serum, it was still active enough to eradication of bacteria at low concentrations. Compared with standard condition (MHB only), there was no significant decrease in antibacterial activity of PV3 against P. aeruginosa strains under 150 mM NaCl (p = 0.615) and 1 mM MgCl 2 (p = 0.3466). Fluorescence microscopy and field emission scanning electron microscopy further indicated that PV3 killed bacteria by disrupting the cell membrane. Since PV3 has potent anti-pseudomonal activity and has little cytotoxicity in vitro, it seems plausible that the peptide should be further investigated with animal studies to support future pharmacological formulations and potential topical applications. - Highlights: • PV3 killed Pseudomonas aeruginosa by membrane-disrupting mechanism. • PV3 reduced biofilm biomass and viability of biofilm embedded bacteria in a concentration-dependent manner. • Short hybrid antimicrobial peptide PV3 exhibited higher and faster bactericidal activity comparing to ceftazidime.

Fragment library screening identifies hits that bind to the non-catalytic surface of Pseudomonas aeruginosa DsbA1

Science.gov (United States)

Headey, Stephen J.; Vazirani, Mansha; Shouldice, Stephen R.; Coinçon, Mathieu; Tay, Stephanie; Morton, Craig J.; Simpson, Jamie S.; Martin, Jennifer L.

2017-01-01

At a time when the antibiotic drug discovery pipeline has stalled, antibiotic resistance is accelerating with catastrophic implications for our ability to treat bacterial infections. Globally we face the prospect of a future when common infections can once again kill. Anti-virulence approaches that target the capacity of the bacterium to cause disease rather than the growth or survival of the bacterium itself offer a tantalizing prospect of novel antimicrobials. They may also reduce the propensity to induce resistance by removing the strong selection pressure imparted by bactericidal or bacteriostatic agents. In the human pathogen Pseudomonas aeruginosa, disulfide bond protein A (PaDsbA1) plays a central role in the oxidative folding of virulence factors and is therefore an attractive target for the development of new anti-virulence antimicrobials. Using a fragment-based approach we have identified small molecules that bind to PaDsbA1. The fragment hits show selective binding to PaDsbA1 over the DsbA protein from Escherichia coli, suggesting that developing species-specific narrow-spectrum inhibitors of DsbA enzymes may be feasible. Structures of a co-complex of PaDsbA1 with the highest affinity fragment identified in the screen reveal that the fragment binds on the non-catalytic surface of the protein at a domain interface. This biophysical and structural data represent a starting point in the development of higher affinity compounds, which will be assessed for their potential as selective PaDsbA1 inhibitors. PMID:28346540

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.

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

Anti-Pseudomonas aeruginosa IgY Antibodies Induce Specific Bacterial Aggregation and Internalization in Human Polymorphonuclear Neutrophils

DEFF Research Database (Denmark)

Thomsen, K.; Christophersen, L.; Bjarnsholt, T.

2015-01-01

with P. aeruginosa by augmenting the phagocytic competence of PMNs may postpone the deteriorating chronic biofilm infection. Anti-P. aeruginosa IgY antibodies significantly increase the PMN-mediated respiratory burst and subsequent bacterial killing of P. aeruginosa in vitro. The mode of action...... is attributed to IgY-facilitated formation of immobilized bacteria in aggregates, as visualized by fluorescence microscopy and the induction of increased bacterial hydrophobicity. Thus, the present study demonstrates that avian egg yolk immunoglobulins (IgY) targeting P. aeruginosa modify bacterial fitness...

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.

Effects of Chinese medicinal herbs on a rat model of chronic Pseudomonas aeruginosa lung infection.

Science.gov (United States)

Song, Z; Johansen, H K; Moser, C; Høiby, N

1996-05-01

The aim of the study was to evaluate the effects of two kinds of Chinese medicinal herbs, Isatis tinctoria L (ITL) and Daphne giraldii Nitsche (DGN), on a rat model of chronic Pseudomonas aeruginosa lung infection mimicking cystic fibrosis (CF). Compared to the control group, both drugs were able to reduce the incidence of lung abscess (p < 0.05) and to decrease the severity of the macroscopic pathology in lungs (p < 0.05). In the great majority of the rats, the herbs altered the inflammatory response in the lungs from an acute type inflammation, dominated by polymorphonuclear leukocytes (PMN), to a chronic type inflammation, dominated by mononuclear leukocytes (MN). DGN also improved the clearance of P. aeruginosa from the lungs (p < 0.03) compared with the control group. There were no significant differences between the control group and the two herbal groups with regard to serum IgG and IgA anti-P. aeruginosa sonicate antibodies. However, the IgM concentration in the ITL group was significantly lower than in the control group (p < 0.03). These results suggest that the two medicinal herbs might be helpful to CF patients with chronic P. aeruginosa lung infection, DGN being the most favorable.

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...

Characterization of five ECF sigma factors in the genome of Pseudomonas syringae pv. syringae B728a.

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Poulami Basu Thakur

Full Text Available Pseudomonas syringae pv. syringae B728a, a bacterial pathogen of bean, utilizes large surface populations and extracellular signaling to initiate a fundamental change from an epiphytic to a pathogenic lifestyle. Extracytoplasmic function (ECF sigma (σ factors serve as important regulatory factors in responding to various environmental signals. Bioinformatic analysis of the B728a genome revealed 10 ECF sigma factors. This study analyzed deletion mutants of five previously uncharacterized ECF sigma factor genes in B728a, including three FecI-type ECF sigma factors (ECF5, ECF6, and ECF7 and two ECF sigma factors placed in groups ECF11 and ECF18. Transcriptional profiling by qRT-PCR analysis of ECF sigma factor mutants was used to measure expression of their associated anti-sigma and outer membrane receptor proteins, and expression of genes associated with production of extracellular polysaccharides, fimbriae, glycine betaine and syringomycin. Notably, the B728aΔecf7 mutant displayed reduced swarming and had decreased expression of CupC fimbrial genes. Growth and pathogenicity assays, using a susceptible bean host, revealed that none of the tested sigma factor genes are required for in planta growth and lesion formation.

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.

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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

Biocidal properties of anti-icing additives for aircraft fuels.

Science.gov (United States)

Neihof, R A; Bailey, C A

1978-04-01

The biocidal and biostatic activities of seven glycol monoalkyl ether compounds were evaluated as part of an effort to find an improved anti-icing additive for jet aircraft fuel. Typical fuel contaminants, Cladosporium resinae, Gliomastix sp., Candida sp., Pseudomonas aeruginosa, and a mixed culture containing sulfate-reducing bacteria were used as assay organisms. Studies were carried out over 3 to 4 months in two-phase systems containing jet fuel and aqueous media. Diethylene glycol monomethyl ether, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, and 2-methoxyethanol were generally biocidal in aqueous concentrations of 10 to 17% for all organisms except Gliomastix, which required 25% or more. 2-Ethoxyethanol, 2-propoxyethanol, and 2-butoxyethanol were biocidal at progressively lower concentrations down to 1 to 2% for 2-butoxyethanol. The enhanced antimicrobial activity of these three compounds was attributed to cytoplasmic membrane damage because of the correlation between surface tension measurements and lytic activity with P. aeruginosa cells. The mechanism of action of the less active compounds appeared to be due to osmotic (dehydrating) effects. When all requirements are taken into account, diethylene glycol monomethyl ether appears to be the most promising replacement for the currently used additive, 2-methoxyethanol.

Anti-mutated citrullinated vimentin (anti-MCV) and anti-65 kDa heat shock protein (anti-hsp65): new biomarkers in ankylosing spondylitis.

Science.gov (United States)

Bodnár, Nóra; Szekanecz, Zoltán; Prohászka, Zoltán; Kemény-Beke, Adám; Némethné-Gyurcsik, Zsuzsanna; Gulyás, Katalin; Lakos, Gabriella; Sipka, Sándor; Szántó, Sándor

2012-01-01

Citrullination as well as anti-citrullinated protein/peptide antibodies (ACPA) have been implicated in the pathogenesis of rheumatoid arthritis (RA). While ACPAs are specific and sensitive markers for RA, there have been hardly any reports regarding ACPAs in ankylosing spondylitis (AS). The possible role of antibodies to Mycobacterial 65 kDa heat shock protein (hsp65) has not been characterized in AS. As new laboratory biomarkers of AS are needed, we investigated the prevalence of anti-mutated citrullinated vimentin (MCV) and anti-hsp65 antibodies in AS. Altogether 43 AS and 44 healthy controls were included in the study. Anti-MCV and anti-hsp65 were determined in sera by commercial and in-house ELISA, respectively. Serum autoantibody levels were correlated with ESR, CRP, HLA-B27 status, smoking habits, pain intensity, BASDAI, BASFI and BASMI indices. Patients with AS had significantly higher serum anti-MCV levels (17.3 U/mL, range: 8.3-31.5 U/mL) in comparison to healthy subjects (8.9 U/mL, range: 5.4-13.3 U/mL) (p20 U/mL). The mean anti-hsp65 concentration in AS sera was 124.8 AU/mL (range: 27.2-1000 AU/mL), while controls exerted significantly lower anti-hsp65 levels (mean: 51.8 AU/mL; range: 22.5-88.5 AU/mL) (p<0.001). Correlation analysis revealed that both anti-MCV positivity (r=0.613; p=0.012) and absolute serum anti-MCV levels (r=0.553; p=0.021) correlated with anti-hsp65 levels. Anti-MCV positivity also correlated with ESR (r=0.437; p=0.03). Anti-MCV and anti-hsp65 may be novel biomarkers in AS. Copyright © 2011. Published by Elsevier SAS.

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

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

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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

Transfer of several phytopathogenic Pseudomonas species to Acidovorax as Acidovorax avenae subsp. avenae subsp. nov., comb. nov., Acidovorax avenae subsp. citrulli, Acidovorax avenae subsp. cattleyae, and Acidovorax konjaci.

Science.gov (United States)

Willems, A; Goor, M; Thielemans, S; Gillis, M; Kersters, K; De Ley, J

1992-01-01

DNA-rRNA hybridizations, DNA-DNA hybridizations, polyacrylamide gel electrophoresis of whole-cell proteins, and a numerical analysis of carbon assimilation tests were carried out to determine the relationships among the phylogenetically misnamed phytopathogenic taxa Pseudomonas avenae, Pseudomonas rubrilineans, "Pseudomonas setariae," Pseudomonas cattleyae, Pseudomonas pseudoalcaligenes subsp. citrulli, and Pseudomonas pseudoalcaligenes subsp. konjaci. These organisms are all members of the family Comamonadaceae, within which they constitute a separate rRNA branch. Only P. pseudoalcaligenes subsp. konjaci is situated on the lower part of this rRNA branch; all of the other taxa cluster very closely around the type strain of P. avenae. When they are compared phenotypically, all of the members of this rRNA branch can be differentiated from each other, and they are, as a group, most closely related to the genus Acidovorax. DNA-DNA hybridization experiments showed that these organisms constitute two genotypic groups. We propose that the generically misnamed phytopathogenic Pseudomonas species should be transferred to the genus Acidovorax as Acidovorax avenae and Acidovorax konjaci. Within Acidovorax avenae we distinguished the following three subspecies: Acidovorax avenae subsp. avenae, Acidovorax avenae subsp. cattleyae, and Acidovorax avenae subsp. citrulli. Emended descriptions of the new taxa are presented.

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

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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.

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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

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)

Impact du séchage sur la viabilité de Pseudomonas fluorescens (synthèse bibliographique

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Mputu Kanyinda, JN.

2014-01-01

Full Text Available Impact of drying on Pseudomonas fluorescens viability. A review. Drying Pseudomonas fluorescens makes for more economical storage, transportation and marketing. The aim of the drying process is to stop and to stabilize all biological activity for optimal storage, compatible with the conservation of the maximum desired viability of the microorganisms. However, the viability rate of the bacteria after drying depends on the operating conditions of the drying process. One of the most important criteria to consider during the drying of biologically active products is the quality of the final dried product. Freeze-drying is the drying method most commonly used for Pseudomonas fluorescens. After their production, the bacteria are harvested by centrifugation and are freeze-dried, but the changes in temperature induced by freeze-drying are not without consequence for the cells. The freeze-drying process induces cell damage: peroxidation of fatty acids and proteins and DNA oxidation. However, use of protective compounds during freeze-drying and during storage increases significantly the rate of cell viability.

Silver against Pseudomonas aeruginosa biofilms

DEFF Research Database (Denmark)

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

2007-01-01

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

Investigation of the decays anti B0 → D*+l-anti ν and anti B → D**l-anti ν

International Nuclear Information System (INIS)

Albrecht, H.; Ehrlichmann, H.; Hamacher, T.; Hofmann, R.P.; Kirchhoff, T.; Nau, A.; Nowak, S.; Schroeder, H.; Schulz, H.D.; Walter, M.; Wurth, R.; Appuhn, R.D.; Hast, C.; Kolanoski, H.; Lange, A.; Lindner, A.; Mankel, R.; Schieber, M.; Siegmund, T.; Spaan, B.; Thurn, H.; Toepfer, D.; Walther, A.; Wegener, D.; Britton, D.I.; Charlesworth, C.E.K.; Edwards, K.W.; Hyatt, E.R.F.; Kapitza, H.; Krieger, P.; MacFarlane, D.B.; Patel, P.M.; Prentice, J.D.; Saull, P.R.B.; Tzamariudaki, K.; Van de Water, R.G.; Yoon, T.S.; Ressing, D.; Schmidtler, M.; Schneider, M.; Schubert, K.R.; Strahl, K.; Waldi, R.; Weseler, S.

1993-01-01

Exclusive semileptonic B decays with a D *+ meson in the final state have been studied using the ARGUS detector at the DORIS II storage ring. The branching ratio for the decay anti B 0 →D *+ l - anti ν, where l - is either e - or μ - , has been measured to be (5.2±0.5±0.6)%. A significant rate for the decay anti B→D ** l - anti ν has been observed. From an angular analysis of the cascade anti B 0 →D *+ (→D 0 π + )l - anti ν the forward-backward asymmetry A FB and the D *+ polarization parameter α have been determined to be A FB =0.20±0.08±0.06 and α=1.1±0.4±0.2. (orig.)

Pseudomonas Endocarditis with an unstable phenotype: the challenges of isolate characterization and Carbapenem stewardship with a partial review of the literature

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Emil Lesho

2017-08-01

transcriptome analysis, and multiple sequence alignment, might have revealed the mechanism and better informed the optimal choice of β-lactam, such approaches are neither rapid, nor feasible for hospital laboratories. In this era of escalating drug resistance and dwindling antibiotics, use of the most potent anti-pseudomonals must be balanced with stewardship. Clinicians need access to validated genomic correlates of resistance, and faster, more informative diagnostics. Therefore, we placed these isolates and their sequences in the public domain for inclusion in the Pseudomonas pan-genome and database projects for further countermeasure development.

Pseudomonas Endocarditis with an unstable phenotype: the challenges of isolate characterization and Carbapenem stewardship with a partial review of the literature.

Science.gov (United States)

Lesho, Emil; Snesrud, Erik; Kwak, Yoon; Ong, Ana; Maybank, Rosslyn; Laguio-Vila, Maryrose; Falsey, Ann R; Hinkle, Mary

2017-01-01

, might have revealed the mechanism and better informed the optimal choice of β-lactam, such approaches are neither rapid, nor feasible for hospital laboratories. In this era of escalating drug resistance and dwindling antibiotics, use of the most potent anti-pseudomonals must be balanced with stewardship. Clinicians need access to validated genomic correlates of resistance, and faster, more informative diagnostics. Therefore, we placed these isolates and their sequences in the public domain for inclusion in the Pseudomonas pan-genome and database projects for further countermeasure development.