Journal articles on the topic 'Pyocyanin'
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O'Malley, Yunxia Q., Maher Y. Abdalla, Michael L. McCormick, Krzysztof J. Reszka, Gerene M. Denning, and Bradley E. Britigan. "Subcellular localization ofPseudomonaspyocyanin cytotoxicity in human lung epithelial cells." American Journal of Physiology-Lung Cellular and Molecular Physiology 284, no. 2 (February 1, 2003): L420—L430. http://dx.doi.org/10.1152/ajplung.00316.2002.
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The Pseudomonas aeruginosa secretory product pyocyanin damages lung epithelium, likely due to redox cycling of pyocyanin and resultant superoxide and H2O2generation. Subcellular site(s) of pyocyanin redox cycling and toxicity have not been well studied. Therefore, pyocyanin's effects on subcellular parameters in the A549 human type II alveolar epithelial cell line were examined. Confocal and electron microscopy studies suggested mitochondrial redox cycling of pyocyanin and extracellular H2O2release, respectively. Pyocyanin decreased mitochondrial and cytoplasmic aconitase activity, ATP levels, cellular reduction of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide, and mitochondrial membrane potential. These effects were transient at low pyocyanin concentrations and were linked to apparent cell-mediated metabolism of pyocyanin. Overexpression of MnSOD, but not CuZnSOD or catalase, protected cellular aconitase, but not ATP, from pyocyanin-mediated depletion. This suggests that loss of aconitase activity is not responsible for ATP depletion. How pyocyanin leads to ATP depletion, the mechanism of cellular metabolism of pyocyanin, and the impact of mitochondrial pyocyanin redox cycling on other cellular events are important areas for future study.
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O'Malley, Yunxia Q., Krzysztof J. Reszka, George T. Rasmussen, Maher Y. Abdalla, Gerene M. Denning, and Bradley E. Britigan. "ThePseudomonassecretory product pyocyanin inhibits catalase activity in human lung epithelial cells." American Journal of Physiology-Lung Cellular and Molecular Physiology 285, no. 5 (November 2003): L1077—L1086. http://dx.doi.org/10.1152/ajplung.00198.2003.
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Pyocyanin, produced by Pseudomonas aeruginosa, has many deleterious effects on human cells that relate to its ability to generate reactive oxygen species (ROS), such as superoxide and hydrogen peroxide. Human cells possess several mechanisms to protect themselves from ROS, including manganese superoxide dismutase (MnSOD), copper zinc superoxide dismutase (CuZnSOD), and catalase. Given the link between pyocyanin-mediated epithelial cell injury and oxidative stress, we assessed pyocyanin's effect on MnSOD, CuZnSOD, and catalase levels in the A549 human alveolar epithelial cell line and in normal human bronchial epithelial cells. In both cell types, CuZnSOD and MnSOD were unaltered, but over 24 h pyocyanin significantly decreased cellular catalase activity and protein content. Pyocyanin also decreased catalase mRNA. Overexpression of MnSOD in A549 cells prevented pyocyanin-mediated loss of catalase protein, but catalase activity still declined. Furthermore, pyocyanin decreased catalase activity, but not protein, in A549 cells overexpressing human catalase. These data suggest a direct effect of pyocyanin on catalase activity. Addition of pyocyanin to catalase in a cell-free system also decreased catalase activity. Mammalian catalase binds four NADPH molecules, helping maintain enzyme activity. Spin-trapping data suggest that pyocyanin directly oxidizes this NADPH, producing superoxide. We conclude that pyocyanin may decrease cellular catalase activity via both transcriptional regulation and direct inactivation of the enzyme. Decreased cellular catalase activity and failure to augment MnSOD could contribute to pyocyanin-dependent cytotoxicity.
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O'Malley, Yunxia Q., Krzysztof J. Reszka, Douglas R. Spitz, Gerene M. Denning, and Bradley E. Britigan. "Pseudomonas aeruginosapyocyanin directly oxidizes glutathione and decreases its levels in airway epithelial cells." American Journal of Physiology-Lung Cellular and Molecular Physiology 287, no. 1 (July 2004): L94—L103. http://dx.doi.org/10.1152/ajplung.00025.2004.
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Production of pyocyanin enhances Pseudomonas aeruginosa virulence. Many of pyocyanin's in vitro and in vivo cytotoxic effects on human cells appear to result from its ability to redox cycle. Pyocyanin directly accepts electrons from NADH or NADPH with subsequent electron transfer to oxygen, generating reactive oxygen species. Reduced glutathione (GSH) is an important cellular antioxidant, and it contributes to the regulation of redox-sensitive signaling systems. Using the human bronchial epithelial (HBE) and the A549 human type II alveolar epithelial cell lines, we tested the hypothesis that pyocyanin can deplete airway epithelial cells of GSH. Incubation of both cell types with pyocyanin led to a concentration-dependent loss of cellular GSH (up to 50%) and an increase in oxidized GSH (GSSG) in the HBE, but not A549 cells, at 24 h. An increase in total GSH, mostly as GSSG, was detected in the culture media, suggesting export of GSH or GSSG from the pyocyanin-exposed cells. Loss of GSH could be due to pyocyanin-induced H2O2formation. However, overexpression of catalase only partially prevented the pyocyanin-mediated decline in cellular GSH. Cell-free electron paramagnetic resonance studies revealed that pyocyanin directly oxidizes GSH, forming pyocyanin free radical and O2−·. Pyocyanin oxidized other thiol-containing compounds, cysteine and N-acetyl-cysteine, but not methionine. Thus GSH may enhance pyocyanin-induced cytotoxicity by functioning as an alternative source of reducing equivalents for pyocyanin redox cycling. Pyocyanin-mediated alterations in cellular GSH may alter epithelial cell functions by modulating redox sensitive signaling events.
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فاطمة حسين بريج مورد, رغد أكرم عزيز, and محمد فرج شذر. "العلاقة التأزرية لصبغة البايوسيانين pyocyaninالمنتجة من بكتريا Pseudomonasaeruginosa و خميرة Saccharomyces cerevisiaeتجاه بعض انواع البكتريا المرضية و المعزولة من عينات سريرية متعددة." journal of the college of basic education 22, SI (August 24, 2022): 237–57. http://dx.doi.org/10.35950/cbej.v22isi.5898.
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تضمنت الدراسة تأكيد تشخيص 29 عزلة من بكتريا Pseudomonasaeruginosaبالأعتماد على الفحوص الزرعية و المجهرية و الكيموحيوية , وعزلتين منخميرة Saccharomyces cerevisiae, فضلا عن جمع 12 عزلة مرضية من عينات سريرية متعددة من بعض مستشفيات مدينة الطب شملت كلا من Staphylococcusaureus , Escherichia coli, و تم تأكيد تشخيص جميع العزلات بنظام VITEK2 وحسب الكارت الخاص بالبكتريا السالبة و الموجبة لصبغة كرام بالإضافة للكارت الخاص بالخميرة ,ثم اجريت غربلة لبكتريا Pseudomonasaeruginosaالمعزولة من الجروح و الحروقو القشع لغرض اختيار العزلة الأكفأ في انتاج صبغة البايوسيانين pyocyanin اذ بينت النتائج ان عزلة الجروح التي تمتلك اعلى تركيز و سجلت اعلى درجة امتصاصية هي الافضل في انتاج صبغة البايوسيانين pyocyanin , اختبرت حساسية البكتريا المرضية تجاه 10 انواع من المضادات الحياتية , وبينت النتائج ان اغلب العزلات مقاومة لمضادات (Ciprofloxacin, Imipenem, Amikacin) و متباينة التأثير لبقية المضادات , هذا و استعملت خمائر الخبز الجافة للحصول على عزلات خميرة Saccharomyces cerevisiae التي شملت كل من العزلةBy 1 من الخميرة Super mayaالصينية المنشأ والعزلة By2 من خميرة Glorpan الصينية المنشأ .كما أجريت غربلة لعزلات خميرة S.cerevisiae من اجل انتخاب العزلة الاكفأ في انتاج البروتينات المثبطة بإستعمال طريقة الانتشار في الحفر لمعرفة تأثير هذه المواد تجاه البكتريا المرضية قيد الدراسة , و قد اظهرت النتائج ان العزلة By 1 أعطت اعلى معدل تثبيط تجاه العزلات S .aureus , E .coli من العزلة By 2. ايضا تمقياس التركيز المثبط الادنى MIC لكل من صبغة البايوسيانين Pyocyaninو راشح خميرة S.cerevisiae تجاه العزلات البكتيرية قيد الدراسة و بإستعمال طريقة العكارة في الانابيب , واثبتت النتائج ان قيمة MIC كانت متباينة حسب تركيز الراشح و فعاليته و حسب تدرج البكتريا المرضية . كما درست العلاقة التأزرية بين صبغة البايوسيانين Pyocyanin و راشح S.cerevisiae تجاه البكتريا المرضية التي تم اختيارها لهذا الاختبار حسب درجة مقاومتها للمضادات الحيوية ,اذ اظهرت النتائج ان العلاقة كانت تآزرية و لا وجود لأي علاقة اخرى بسبب فعالية الصبغة مع الراشح على تثبيط فعل البكتريا المرضية . لذلك توصي الدراسة على التركيز على صبغة البايوسيانين Pyocyaninمع خميرةSaccharomycescerevisiae (كخلية كاملة او المواد المثبطة التي تنتجها ( علاجاللإصابات التي تسببها بعض انواع البكتريا المرضية .
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Jain, Preeti, Suman Kumari, and Ashish Malik. "INHIBITION OF PYOCYANIN PRODUCTION IN PSEUDOMONAS AERUGINOSA BY NATURAL ANTIMICROBIAL COMPOUNDS FROM HERBAL EXTRACTS." Asian Journal of Pharmaceutical and Clinical Research 10, no. 6 (June 1, 2017): 389. http://dx.doi.org/10.22159/ajpcr.2017.v10i6.18056.
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Objective: P. aeruginosa produces a range of metabolites including pyocyanin that enhance its ability to resist antibiotics and becomes capable of surviving adverse conditions.Method: In this report, eight plants (extracted with five solvents) were screened for antibacterial activity against P. aeruginosa by microbroth dilution method. Afterward tested for inhibition of pyocyanin in presence and absence of plant extracts.Result: Among these D. muricata and S. quitoenes exhibited good antibacterial potential. Inhibition of pyocyanin is identified as a potential anti-virulence strategy. Therefore, acetone extract of six plants exhibited MIC ≤3.125mg/ml and methanol extract of three plants exhibited MIC ≤6.25mg/ml were used to check pyocyanin inhibition in P. aeruginosa. In acetone extracts, significant pyocyanin inhibition was found in I. pestigirdis and C. colocynthis. In methanol extracts, C. colocynthis and D. muricata showed considerable pyocyanin inhibition.Conclusion: Overall result indicates that the best antimicrobial compound (growth inhibitor) may not be best inhibitor of pyocyanin biosynthesis or vice-versa. Moreover, I. pestigirdis, C. colocynthis and D. muricata seems to contain compounds which inhibit the growth of bacteria as well as the biosynthesis of pyocyanin.
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De Vleesschauwer, David, Pierre Cornelis, and Monica Höfte. "Redox-Active Pyocyanin Secreted by Pseudomonas aeruginosa 7NSK2 Triggers Systemic Resistance to Magnaporthe grisea but Enhances Rhizoctonia solani Susceptibility in Rice." Molecular Plant-Microbe Interactions® 19, no. 12 (December 2006): 1406–19. http://dx.doi.org/10.1094/mpmi-19-1406.
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Pseudomonas aeruginosa 7NSK2 induces resistance in dicots through a synergistic interaction of the phenazine pyocyanin and the salicylic acid-derivative pyochelin. Root inoculation of the monocot model rice with 7NSK2 partially protected leaves against blast disease (Magnaporthe grisea) but failed to consistently reduce sheath blight (Rhizoctonia solani). Only mutations interfering with pyocyanin production led to a significant decrease in induced systemic resistance (ISR) to M. grisea, and in trans complementation for pyocyanin production restored the ability to elicit ISR. Intriguingly, pyocyanin-deficient mutants, unlike the wild type, triggered ISR against R. solani. Hence, bacterial pyocyanin plays a differential role in 7NSK2-mediated ISR in rice. Application of purified pyocyanin to hydroponically grown rice seedlings increased H2O2 levels locally on the root surface as well as a biphasic H2O2 generation pattern in distal leaves. Co-application of pyocyanin and the antioxidant sodium ascorbate alleviated the opposite effects of pyocyanin on rice blast and sheath blight development, suggesting that the differential effectiveness of pyocyanin with respect to 7NSK2-triggered ISR is mediated by transiently elevated H2O2 levels in planta. The cumulative results suggest that reactive oxygen species act as a double-edged sword in the interaction of rice with the hemibiotroph M. grisea and the necrotroph R. solani.
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Pragana, Luiz Gustavo, Carlos Eduardo Tavares Norat, Diogo Simas Bernardes Dias, Elisângela Afonso de Moura Kretzschmar, Rafael de Almeida Travassos, and Ulrich Vasconcelos. "Summary of the role of pyocyanin in the transformation and biodegradation of Polycyclic Aromatic Hydrocarbons." Conjecturas 22, no. 15 (November 3, 2022): 405–29. http://dx.doi.org/10.53660/conj-1874-2p12.
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Pyocyanin is an active redox phenazine of intense blue color and specific to Pseudomonas aeruginosa. The synthesis of the molecule confers different benefits to the bacterium. Pyocyanin can control its growth and persistence in environments with high nutritional pressures, forming biofilms. As well, synthesis of pyocyanin enables P. aeruginosa tolerate and uptake highly toxic compounds such as polycyclic aromatic hydrocarbons (PAHs), considered the most dangerous compounds among all molecules found in crude oil and petroderivatives. Additionally, pyocyanin increases the bioavailability of PAHs and its metabolites are used to synthetize crucial molecules for the biodegradation of other PAHs. On the other hand, oil hydrocarbons can serve as oxygen vectors during the synthesis of pyocyanin, contributing to the sustainability of the biodegradation process. This review is a compilation of recent advances reported in the literature about the relationship between pyocyanin expression and the hydrocarbonoclastic activity of P. aeruginosa. This characteristic, for the pyocyanin-deficient strains, is important for the degradation of PAHs, a topic that has been unevenly studied.
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Price-Whelan, Alexa, Lars E. P. Dietrich, and Dianne K. Newman. "Pyocyanin Alters Redox Homeostasis and Carbon Flux through Central Metabolic Pathways in Pseudomonas aeruginosa PA14." Journal of Bacteriology 189, no. 17 (May 25, 2007): 6372–81. http://dx.doi.org/10.1128/jb.00505-07.
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ABSTRACT The opportunistic pathogen Pseudomonas aeruginosa produces colorful, redox-active antibiotics called phenazines. Excretion of pyocyanin, the best-studied natural phenazine, is responsible for the bluish tint of sputum and pus associated with P. aeruginosa infections in humans. Although the toxicity of pyocyanin for other bacteria, as well as its role in eukaryotic infection, has been studied extensively, the physiological relevance of pyocyanin metabolism for the producing organism is not well understood. Pyocyanin reduction by P. aeruginosa PA14 is readily observed in standing liquid cultures that have consumed all of the oxygen in the medium. We investigated the physiological consequences of pyocyanin reduction by assaying intracellular concentrations of NADH and NAD+ in the wild-type strain and a mutant defective in phenazine production. We found that the mutant accumulated more NADH in stationary phase than the wild type. This increased accumulation correlated with a decrease in oxygen availability and was relieved by the addition of nitrate. Pyocyanin addition to a phenazine-null mutant also decreased intracellular NADH levels, suggesting that pyocyanin reduction facilitates redox balancing in the absence of other electron acceptors. Analysis of extracellular organic acids revealed that pyocyanin stimulated stationary-phase pyruvate excretion in P. aeruginosa PA14, indicating that pyocyanin may also influence the intracellular redox state by decreasing carbon flux through central metabolic pathways.
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Norman, R. Sean, Peter Moeller, Thomas J. McDonald, and Pamela J. Morris. "Effect of Pyocyanin on a Crude-Oil-Degrading Microbial Community." Applied and Environmental Microbiology 70, no. 7 (July 2004): 4004–11. http://dx.doi.org/10.1128/aem.70.7.4004-4011.2004.
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ABSTRACT Pseudomonas aeruginosa is an n-alkane degrader that is frequently isolated from petroleum-contaminated sites and produces factors that enhance its competitiveness and survival in many environments. In this study, one such factor, pyocyanin, has been detected in an oil-degrading culture containing P. aeruginosa and is a redox-active compound capable of inhibiting microbial growth. To examine the effects of pyocyanin further, an oil-degrading culture was grown with and without 9.5 μM pyocyanin and microbial community structure and oil degradation were monitored for 50 days. Denaturing gradient gel electrophoresis (DGGE) analysis of cultures revealed a decrease in the microbial community diversity in the pyocyanin-amended cultures compared to that of the unamended cultures. Two members of the microbial community in pure culture exhibited intermediate and high sensitivities to pyocyanin corresponding to intermediate and low levels of activity for the antioxidant enzymes catalase and superoxide dismutase, respectively. Another member of the community that remained constant in the DGGE gels over the 50-day culture incubation period exhibited no sensitivity to pyocyanin, corresponding to a high level of catalase and superoxide dismutase when examined in pure culture. Pyocyanin also affected the overall degradation of the crude oil. At 50 days, the culture without pyocyanin had decreased polycyclic aromatic hydrocarbons compared to the pyocyanin-amended culture, with a specific reduction in the degradation of dibenzothiophenes, naphthalenes, and C29 and C30 hopanes. This study demonstrated that pyocyanin influenced the diversity of the microbial community and suggests the importance of understanding how interspecies interactions influence the degradation capability of a microbial community.
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Cheluvappa, Rajkumar, Ronald Shimmon, Michael Dawson, Sarah N. Hilmer, and David G. Le Couteur. "Reactions of Pseudomonas aeruginosa pyocyanin with reduced glutathione." Acta Biochimica Polonica 55, no. 3 (September 17, 2008): 571–80. http://dx.doi.org/10.18388/abp.2008_3063.
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Pseudomonas aeruginosa is the most common cause of chronic and recurrent lung infections in patients with cystic fibrosis (CF) whose sputa contain copious quantities of P. aeruginosa toxin, pyocyanin. Pyocyanin triggers tissue damage mainly by its redox cycling and induction of reactive oxygen species (ROS). The reactions between reduced glutathione (GSH) and pyocyanin were observed using absorption spectra from spectrophotometry and the reaction products analysed by nuclear magnetic resonance imaging. Pyocyanin reacted with GSH non-enzymatically at 37 degrees C resulting in the production of red-brown products, spectophotometrically visible as a 480 nm maximum absorption peak after 24 h of incubation. The reaction was concentration-dependent on reduced glutathione but not on pyocyanin. Minimizing the accessibility of oxygen to the reaction decreased its rate. The anti-oxidant enzyme catalase circumvented the reaction. Proton-NMR analysis demonstrated the persistence of the original aromatic ring and the methyl-group of pyocyanin in the red-brown products. Anti-oxidant agents having thiol groups produced similar spectophotometrically visible peaks. The presence of a previously unidentified non-enzymatic GSH-dependent metabolic pathway for pyocyanin has thus been identified. The reaction between pyocyanin and GSH is concentration-, time-, and O(2)-dependent. The formation of H(2)O(2) as an intermediate and the thiol group in GSH seem to be important in this reaction.
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Bacame-Valenzuela, Francisco Javier, Jesús Alberto Pérez-Garcia, Mayra Leticia Figueroa-Magallón, Fabricio Espejel-Ayala, Luis Antonio Ortiz-Frade, and Yolanda Reyes-Vidal. "Optimized Production of a Redox Metabolite (pyocyanin) by Pseudomonas aeruginosa NEJ01R Using a Maize By-Product." Microorganisms 8, no. 10 (October 10, 2020): 1559. http://dx.doi.org/10.3390/microorganisms8101559.
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Pseudomonas aeruginosa metabolizes pyocyanin, a redox molecule related to diverse biological activities. Culture conditions for the production of pyocyanin in a defined medium were optimized using a statistical design and response surface methodology. The obtained conditions were replicated using as substrate an alkaline residual liquid of cooked maize and its by-products. The untreated effluent (raw nejayote, RN) was processed to obtain a fraction without insoluble solids (clarified fraction, CL), then separated by a 30 kDa membrane where two fractions, namely, retentate (RE) and filtered (FI), were obtained. Optimal conditions in the defined medium were 29.6 °C, 223.7 rpm and pH = 6.92, which produced 2.21 μg mL−1 of pyocyanin, and by using the wastewater, it was possible to obtain 3.25 μg mL−1 of pyocyanin in the retentate fraction at 40 h. The retentate fraction presented the highest concentration of total solids related to the maximum concentration of pyocyanin (PYO) obtained. The pyocyanin redox behavior was analyzed using electrochemical techniques. In this way, valorization of lime-cooked maize wastewater (nejayote) used as a substrate was demonstrated in the production of a value-added compound, such as pyocyanin, a redox metabolite of Pseudomonas aeruginosa NEJ01R.
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Ortiz-Castro, Randy, Ramón Pelagio-Flores, Alfonso Méndez-Bravo, León Francisco Ruiz-Herrera, Jesús Campos-García, and José López-Bucio. "Pyocyanin, a Virulence Factor Produced by Pseudomonas aeruginosa, Alters Root Development Through Reactive Oxygen Species and Ethylene Signaling in Arabidopsis." Molecular Plant-Microbe Interactions® 27, no. 4 (April 2014): 364–78. http://dx.doi.org/10.1094/mpmi-08-13-0219-r.
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Pyocyanin acts as a virulence factor in Pseudomonas aeruginosa, a plant and animal pathogen. In this study, we evaluated the effect of pyocyanin on growth and development of Arabidopsis seedlings. Root inoculation with P. aeruginosa PAO1 strain inhibited primary root growth in wild-type (WT) Arabidopsis seedlings. In contrast, single lasI– and double rhlI–/lasI– mutants of P. aeruginosa defective in pyocyanin production showed decreased root growth inhibition concomitant with an increased phytostimulation. Treatment with pyocyanin modulates root system architecture, inhibiting primary root growth and promoting lateral root and root hair formation without affecting meristem viability or causing cell death. These effects correlated with altered proportions of hydrogen peroxide and superoxide in root tips and with an inhibition of cell division and elongation. Mutant analyses showed that pyocyanin modulation of root growth was likely independent of auxin, cytokinin, and abscisic acid but required ethylene signaling because the Arabidopsis etr1-1, ein2-1, and ein3-1 ethylene-related mutants were less sensitive to pyocyanin-induced root stoppage and reactive oxygen species (ROS) distribution. Our findings suggest that pyocyanin is an important factor modulating the interplay between ROS production and root system architecture by an ethylene-dependent signaling.
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Zeng, Bo, Chong Wang, Pansong Zhang, Zisheng Guo, Lin Chen, and Kangmin Duan. "Heat Shock Protein DnaJ in Pseudomonas aeruginosa Affects Biofilm Formation via Pyocyanin Production." Microorganisms 8, no. 3 (March 12, 2020): 395. http://dx.doi.org/10.3390/microorganisms8030395.
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Heat shock proteins (HSPs) play important biological roles, and they are implicated in bacterial response to environmental stresses and in pathogenesis of infection. The role of HSPs in P. aeruginosa, however, remains to be fully elucidated. Here, we report the unique role of HSP DnaJ in biofilm formation and pathogenicity in P. aeruginosa. A dnaJ mutant produced hardly any pyocyanin and formed significantly less biofilms, which contributed to decreased pathogenicity as demonstrated by reduced mortality rate in a Drosophila melanogaster infection model. The reduced pyocyanin production in the dnaJ mutant was a result of the decreased transcription of phenazine synthesis operons including phzA1, phzA2, phzS, and phzM. The reduction of biofilm formation and initial adhesion in the dnaJ mutant could be reversed by exogenously added pyocyanin or extracellular DNA (eDNA). Consistent with such observations, absence of dnaJ significantly reduced the release of eDNA in P. aeruginosa and addition of exogenous pyocyanin could restore eDNA release. These results indicate dnaJ mutation caused reduced pyocyanin production, which in turn caused the decreased eDNA, resulting in decreased biofilm formation. DnaJ is required for pyocyanin production and full virulence in P. aeruginosa; it affects biofilm formation and initial adhesion via pyocyanin, inducing eDNA release.
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Audenaert, Kris, Theresa Pattery, Pierre Cornelis, and Monica Höfte. "Induction of Systemic Resistance to Botrytis cinerea in Tomato by Pseudomonas aeruginosa 7NSK2: Role of Salicylic Acid, Pyochelin, and Pyocyanin." Molecular Plant-Microbe Interactions® 15, no. 11 (November 2002): 1147–56. http://dx.doi.org/10.1094/mpmi.2002.15.11.1147.
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The rhizobacterium Pseudomonas aeruginosa 7NSK2 produces secondary metabolites such as pyochelin (Pch), its precursor salicylic acid (SA), and the phenazine compound pyocyanin. Both 7NSK2 and mutant KMPCH (Pch-negative, SA-positive) induced resistance to Botrytis cinerea in wild-type but not in transgenic NahG tomato. SA-negative mutants of both strains lost the capacity to induce resistance. On tomato roots, KMPCH produced SA and induced phenylalanine ammonia lyase activity, while this was not the case for 7NSK2. In 7NSK2, SA is probably very efficiently converted to Pch. However, Pch alone appeared not to be sufficient to induce resistance. In mammalian cells, Fe-Pch and pyocyanin can act synergistically to generate highly reactive hydroxyl radicals that cause cell damage. Reactive oxygen species are known to play an important role in plant defense. To study the role of pyocyanin in induced resistance, a pyocyanin-negative mutant of 7NSK2, PHZ1, was generated. PHZ1 is mutated in the phzM gene encoding an O-methyltransferase. PHZ1 was unable to induce resistance to B. cinerea, whereas complementation for pyocyanin production or co-inoculation with mutant 7NSK2-562 (Pch-negative, SA-negative, pyocyanin-positive) restored induced resistance. These results suggest that pyocyanin and Pch, rather than SA, are the determinants for induced resistance in wild-type P. aeruginosa 7NSK2.
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WEBSTER, THADDAEUS A., HUNTER J. SISMAET, and EDGAR D. GOLUCH. "AMPEROMETRIC DETECTION OF PYOCYANIN IN NANOFLUIDIC CHANNELS." Nano LIFE 03, no. 01 (March 2013): 1340011. http://dx.doi.org/10.1142/s1793984413400114.
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Microfabricated nanofluidic electrode assemblies (NEAs) with integrated palladium references were used to amperometrically monitor changes in pyocyanin concentration. Pyocyanin is an electroactive molecule that is produced by the opportunistic pathogen Pseudomonas aeruginosa and is directly linked to cellular processes that increase both robustness and virulence in this bacterium. This is the first time that pyocyanin has been measured in real time using microfabricated sensors. A linear response in faradaic current (R2= 0.96) was observed over a biomedically relevant range of pyocyanin concentrations (0–100 μM) while continuously measuring the current for 2 h. Measurement of the current that results from the repeated oxidation and reduction of pyocyanin at two closely spaced electrodes inside the device nanochannel yielded a 1.07 μM limit of detection without electrical isolation of the electrochemical cell. Since a reference electrode is integrated inside the nanofluidic channel of these sensors, they can potentially be employed to detect pyocyanin and other redox-active molecules in wide range of medical and environmental settings where space is limited. NEAs were also used with an external Ag/AgCl reference electrode to determine the concentration of pyocyanin in trypticase soy broth samples. This type of analysis is completed in less than 2 min and the detection limit was determined to be 441 nM.
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Morkunas, Bernardas, Balint Gal, Warren R. J. D. Galloway, James T. Hodgkinson, Brett M. Ibbeson, Yaw Sing Tan, Martin Welch, and David R. Spring. "Discovery of an inhibitor of the production of the Pseudomonas aeruginosa virulence factor pyocyanin in wild-type cells." Beilstein Journal of Organic Chemistry 12 (July 11, 2016): 1428–33. http://dx.doi.org/10.3762/bjoc.12.137.
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Pyocyanin is a small molecule produced by Pseudomonas aeruginosa that plays a crucial role in the pathogenesis of infections by this notorious opportunistic pathogen. The inhibition of pyocyanin production has been identified as an attractive antivirulence strategy for the treatment of P. aeruginosa infections. Herein, we report the discovery of an inhibitor of pyocyanin production in cultures of wild-type P. aeruginosa which is based around a 4-alkylquinolin-2(1H)-one scaffold. To the best of our knowledge, this is the first reported example of pyocyanin inhibition by a compound based around this molecular framework. The compound may therefore be representative of a new structural sub-class of pyocyanin inhibitors, which could potentially be exploited in in a therapeutic context for the development of critically needed new antipseudomonal agents. In this context, the use of wild-type cells in this study is notable, since the data obtained are of direct relevance to native situations. The compound could also be of value in better elucidating the role of pyocyanin in P. aeruginosa infections. Evidence suggests that the active compound reduces the level of pyocyanin production by inhibiting the cell–cell signalling mechanism known as quorum sensing. This could have interesting implications; quorum sensing regulates a range of additional elements associated with the pathogenicity of P. aeruginosa and there is a wide range of other potential applications where the inhibition of quorum sensing is desirable.
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Amly, Dina Auliya, Puspita Hajardhini, Alma Linggar Jonarta, Heribertus Dedy Kusuma Yulianto, and Heni Susilowati. "Enhancement of pyocyanin production by subinhibitory concentration of royal jelly in Pseudomonas aeruginosa." F1000Research 10 (January 11, 2021): 14. http://dx.doi.org/10.12688/f1000research.27915.1.
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Background: Pseudomonas aeruginosa, a multidrug resistant Gram-negative bacterium, produces pyocyanin, a virulence factor associated with antibiotic tolerance. High concentrations of royal jelly have an antibacterial effect, which may have the potential to overcome antibacterial resistance. However, in some cases, antibiotic tolerance can occur due to prolonged stress of low-dose antibacterial agents. This study aimed to investigate the effect of subinhibitory concentrations of royal jelly on bacterial growth and pyocyanin production of P. aeruginosa. Methods: Pseudomonas aeruginosa ATCC® 10145™ and clinical isolates were cultured in BHI media for 18 hours followed by optical density measurements at 600 nm wavelength to determine minimum inhibitory concentration (MIC). After 36 hours of incubation, pyocyanin production was observed by measuring the absorbance at 690 nm. Pyocyanin concentrations were calculated using extinction coefficient 4310 M-1cm-1. Results: Results of the MIC tests of both strains were 25%. The highest production of pyocyanin was observed in the subinhibitory concentration group 6.25%, which gradually decreased along with the decrease of royal jelly concentration. Results of one-way ANOVA tests differed significantly in pyocyanin production of the two strains between the royal jelly groups. Tukey HSD test showed concentrations of 12.5%, 6.25%, and 3.125% significantly increased pyocyanin production of ATCC® 10145™, and the concentrations of 12.5% and 6.25% significantly increased production of the clinical isolates. Conclusions: This study concluded royal jelly concentrations of 25% or above could inhibit bacterial growth; however, only the concentrations of 12.5% and 6.25% could increase pyocyanin production in P. aeruginosa, both in ATCC® 10145™ and clinical isolates. In conclusion, it is advisable to determine the appropriate concentration of royal jelly to obtain beneficial virulence inhibiting activity.
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Alatraktchi, Fatima AlZahra’a, Winnie E. Svendsen, and Søren Molin. "Electrochemical Detection of Pyocyanin as a Biomarker for Pseudomonas aeruginosa: A Focused Review." Sensors 20, no. 18 (September 13, 2020): 5218. http://dx.doi.org/10.3390/s20185218.
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Pseudomonas aeruginosa (PA) is a pathogen that is recognized for its advanced antibiotic resistance and its association with serious diseases such as ventilator-associated pneumonia and cystic fibrosis. The ability to rapidly detect the presence of pathogenic bacteria in patient samples is crucial for the immediate eradication of the infection. Pyocyanin is one of PA’s virulence factors used to establish infections. Pyocyanin promotes virulence by interfering in numerous cellular functions in host cells due to its redox-activity. Fortunately, the redox-active nature of pyocyanin makes it ideal for detection with simple electrochemical techniques without sample pretreatment or sensor functionalization. The previous decade has seen an increased interest in the electrochemical detection of pyocyanin either as an indicator of the presence of PA in samples or as a tool for quantifying PA virulence. This review provides the first overview of the advances in electrochemical detection of pyocyanin and offers an input regarding the future directions in the field.
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Britigan, Bradley E., Michelle A. Railsback, and Charles D. Cox. "The Pseudomonas aeruginosa Secretory Product Pyocyanin Inactivates α1 Protease Inhibitor: Implications for the Pathogenesis of Cystic Fibrosis Lung Disease." Infection and Immunity 67, no. 3 (March 1, 1999): 1207–12. http://dx.doi.org/10.1128/iai.67.3.1207-1212.1999.
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ABSTRACT α1 Protease inhibitor (α1PI) modulates serine protease activity in the lung. Reactive oxygen species inactivate α1PI, and this process has been implicated in the pathogenesis of a variety of forms of lung injury. An imbalance of protease-antiprotease activity is also detected in the airways of patients with cystic fibrosis-associated lung disease who are infected withPseudomonas aeruginosa. P. aeruginosa secretes pyocyanin, which, through its ability to redox cycle, induces cells to generate reactive oxygen species. We tested the hypothesis that redox cycling of pyocyanin could lead to inactivation of α1PI. When α1PI was exposed to NADH and pyocyanin, a combination that results in superoxide production, α1PI lost its ability to form an inhibitory complex with both porcine pancreatic elastase (PPE) and trypsin. Similarly, addition of pyocyanin to cultures of human airway epithelial cells to which α1PI was also added resulted in a loss of the ability of α1PI to form a complex with PPE or trypsin. Neither superoxide dismutase, catalase, nor dimethylthiourea nor depletion of the media of O2 to prevent formation of reactive oxygen species blocked pyocyanin-mediated inactivation of α1PI. These data raise the possibility that a direct interaction between reduced pyocyanin and α1PI is involved in the process. Consistent with this possibility, pretreatment of α1PI with the reducing agent β-mercaptoethanol also inhibited binding of trypsin to α1PI. These data suggest that pyocyanin could contribute to lung injury in the P. aeruginosa-infected airway of cystic fibrosis patients by decreasing the ability of α1PI to control the local activity of serine proteases.
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Muller, Michael, and Neil D. Merrett. "Pyocyanin Production by Pseudomonas aeruginosa Confers Resistance to Ionic Silver." Antimicrobial Agents and Chemotherapy 58, no. 9 (July 7, 2014): 5492–99. http://dx.doi.org/10.1128/aac.03069-14.
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ABSTRACTSilver in its ionic form (Ag+), but not the bulk metal (Ag0), is toxic to microbial life forms and has been used for many years in the treatment of wound infections. The prevalence of bacterial resistance to silver is considered low due to the nonspecific nature of its toxicity. However, the recent increased use of silver as an antimicrobial agent for medical, consumer, and industrial products has raised concern that widespread silver resistance may emerge.Pseudomonas aeruginosais a common pathogen that produces pyocyanin, a redox toxin and a reductant for molecular oxygen and ferric (Fe3+) ions. The objective of this study was to determine whether pyocyanin reduces Ag+to Ag0, which may contribute to silver resistance due to lower bioavailability of the cation. Using surface plasmon resonance spectroscopy and scanning electron microscopy, pyocyanin was confirmed to be a reductant for Ag+, forming Ag0nanoparticles and reducing the bioavailability of free Ag+by >95% within minutes. Similarly, a pyocyanin-producing strain ofP. aeruginosa(PA14) reduced Ag+but not a pyocyanin-deficient (ΔphzM) strain of the bacterium. Challenge of each strain with Ag+(as AgNO3) gave MICs of 20 and 5 μg/ml for the PA14 and ΔphzMstrains, respectively. Removal of pyocyanin from the medium strain PA14 was grown in or its addition to the medium that ΔphzMmutant was grown in gave MICs of 5 and 20 μg/ml, respectively. Clinical isolates demonstrated similar pyocyanin-dependent resistance to Ag+. We conclude that pseudomonal silver resistance exists independently of previously recognized intracellular mechanisms and may be more prevalent than previously considered.
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Denning, Gerene M., Laura A. Wollenweber, Michelle A. Railsback, Charles D. Cox, Lynn L. Stoll, and Bradley E. Britigan. "Pseudomonas Pyocyanin Increases Interleukin-8 Expression by Human Airway Epithelial Cells." Infection and Immunity 66, no. 12 (December 1, 1998): 5777–84. http://dx.doi.org/10.1128/iai.66.12.5777-5784.1998.
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ABSTRACT Pseudomonas aeruginosa, an opportunistic human pathogen, causes acute pneumonia in patients with hospital-acquired infections and is commonly associated with chronic lung disease in individuals with cystic fibrosis (CF). Evidence suggests that the pathophysiological effects of P. aeruginosa are mediated in part by virulence factors secreted by the bacterium. Among these factors is pyocyanin, a redox active compound that increases intracellular oxidant stress. We find that pyocyanin increases release of interleukin-8 (IL-8) by both normal and CF airway epithelial cell lines and by primary airway epithelial cells. Moreover, pyocyanin synergizes with the inflammatory cytokines tumor necrosis factor alpha and IL-1α. RNase protection assays indicate that increased IL-8 release is accompanied by increased levels of IL-8 mRNA. The antioxidant n -acetyl cysteine, general inhibitors of protein tyrosine kinases, and specific inhibitors of mitogen-activated protein kinases diminish pyocyanin-dependent increases in IL-8 release. Conversely, inhibitors of protein kinases C (PKC) and PKA have no effect. In contrast to its effects on IL-8 expression, pyocyanin inhibits cytokine-dependent expression of the monocyte/macrophage/T-cell chemokine RANTES. Increased release of IL-8, a potent neutrophil chemoattractant, in response to pyocyanin could contribute to the marked infiltration of neutrophils and subsequent neutrophil-mediated tissue damage that are observed inPseudomonas-associated lung disease.
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Mohandas, Laxmi, Anju T. R., and Sarita G. Bhat*. "Confocal and SEM imaging to demonstrate food pathogen- biofilm biocontrol by pyocyanin from Pseudomonas aeruginosa BTRY1." International Journal of Bioassays 6, no. 01 (December 31, 2016): 5218. http://dx.doi.org/10.21746/ijbio.2017.01.007.
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An assortment of redox-active phenazine compounds like pyocyanin with their characteristic blue-green colour are synthesized by Pseudomonas aeruginosa, Gram-negative opportunistic pathogens, which are also considered one of the most commercially valuable microorganisms. In this study, pyocyanin from Pseudomonas aeruginosa BTRY1 from food sample was assessed for its antibiofilm activity by micro titer plate assay against strong biofilm producers belonging to the genera Bacillus, Staphylococcus, Brevibacterium and Micrococcus. Pyocyanin inhibited biofilm activity in very minute concentrations. This was also confirmed by Scanning Electron Microscopy (SEM) and Confocal Laser Scanning Microscopy (CLSM). Both SEM and CLSM helped to visualize the biocontrol of biofilm formation by eight pathogens. The imaging and quantification by CLSM also established the impact of pyocyanin on biofilm-biocontrol mainly in the food industry.
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Donchenko, A. S., V. V. Fomenko, V. G. Vasiliev, V. N. Afonyushkin, N. A. Donchenko, Yu N. Kozlova, and V. Yu Koptev. "THE STUDY OF THE ANTAGONISTIC ACTIVITY OF BACTERIA SUPPRESSING THE SYNTHESIS OF PHENAZINES PSEUDOMONAS AERUGINOSA." Siberian Herald of Agricultural Science 48, no. 5 (January 9, 2019): 23–29. http://dx.doi.org/10.26898/0370-8799-2018-5-3.
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The purpose of the study was the search for microorganisms capable of suppressing quorum feelings associated with the production of phenazines (pyocyanin). The formation of pyocyanine, related to oxyphenazines, is one of the indicators of the quorum-sensing reaction. In order to search for antagonistically active bacterial strains, the microorganisms were co-cullured with the cultures of Pseudomonas aeruginosa wherein the suppression of oxyphenazine production was determined. We used 14 cultures of bacteria from the genera Pseudomonas, Acinetobacter, Enterobacter, Staphylococcus, Microbacterium, Serratia, Sphingobacterium, Lactobacillus, Weisella to find strains suppressing the production of pyocyanin. Piocanin was successively extracted with chloroform and 0.2 M hydrochloric acid, after which its content was determined spectrophotometrically at a wavelength of 520 nm. Several bacterial cultures characterized by the ability to inhibit the production of oxyphenazine in co-cultivation tests with Pseudomonas aeruginosa were found. The identified microorganisms belonged to the microorganisms of the genera Acinetobacter and Pseudomonas, Lactobacillus and Weisella. The Kruskal-Wallis criterion - H (5, N = 21) = 11.86902 is statistically significant (p = 0.0366). The distribution of cultures in the inhibition of the production of oxyphenazines in the experiments on co-cultivation with Pseudomonas aeruginosa was not binomial, which implies the non-random nature of the distribution of cultures according to the results of co-cultivation. Thus, the levels of inhibition of the production of phenazines for different taxa of bacteria in the co-cultivation tests were statistically significantly different from each other. The largest sum of ranks belongs to the group Lactobacillus spp. and this taxon has the greatest effect on the content of phenazines. The decrease in the concentration of fhe final product (pyocyanin), the synthesis of which is initiated by butanol-homoserine lactone, can be associated with the mechanisms of quorum-quenching, and the mechanisms of antagonistic activity of microorganisms that affect the production of the aforementioned metabolites of P. aeruginosa.
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Amly, Dina Auliya, Puspita Hajardhini, Alma Linggar Jonarta, Heribertus Dedy Kusuma Yulianto, and Heni Susilowati. "Enhancement of pyocyanin production by subinhibitory concentration of royal jelly in Pseudomonas aeruginosa." F1000Research 10 (December 7, 2021): 14. http://dx.doi.org/10.12688/f1000research.27915.4.
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Background: Pseudomonas aeruginosa, a multidrug-resistant Gram-negative bacterium, produces pyocyanin, a virulence factor associated with antibiotic tolerance. High concentrations of royal jelly have an antibacterial effect, which may potentially overcome antibacterial resistance. However, in some cases, antibiotic tolerance can occur due to prolonged stress of low-dose antibacterial agents. This study aimed to investigate the effect of subinhibitory concentrations of royal jelly on bacterial growth, pyocyanin production, and biofilm formation of P. aeruginosa. Methods: Pseudomonas aeruginosa ATCC 10145 and clinical isolates were cultured in a royal jelly-containing medium to test the antibacterial activity. Pyocyanin production was observed by measuring the absorbance at 690 nm after 36 h culture and determined using extinction coefficient 4310 M-1 cm-1. Static microtiter plate biofilm assay performed to detect the biofilm formation, followed by scanning electron microscopy. Results: Royal jelly effectively inhibited the viability of both strains from a concentration of 25%. The highest production of pyocyanin was observed in the subinhibitory concentration group 6.25%, which gradually decreased along with the decrease of royal jelly concentration. Results of one-way ANOVA tests differed significantly in pyocyanin production of the two strains between the royal jelly groups. Tukey HSD test showed concentrations of 12.5%, 6.25%, and 3.125% significantly increased pyocyanin production of ATCC 10145, and the concentrations of 12.5% and 6.25% significantly increased production of the clinical isolates. Concentrations of 12.5% and 6.125% significantly induced biofilm formation of P. aeruginosa ATCC 10145, in line with the results of the SEM analysis. Conclusions: The royal jelly concentration of 25% or higher inhibits bacterial growth; however, the subinhibitory concentration increases pyocyanin production and biofilm formation in P. aeruginosa. It is advisable to determine the appropriate concentration of royal jelly to obtain beneficial virulence inhibiting activity.
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Amly, Dina Auliya, Puspita Hajardhini, Alma Linggar Jonarta, Heribertus Dedy Kusuma Yulianto, and Heni Susilowati. "Enhancement of pyocyanin production by subinhibitory concentration of royal jelly in Pseudomonas aeruginosa." F1000Research 10 (September 28, 2021): 14. http://dx.doi.org/10.12688/f1000research.27915.3.
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Background: Pseudomonas aeruginosa, a multidrug-resistant Gram-negative bacterium, produces pyocyanin, a virulence factor associated with antibiotic tolerance. High concentrations of royal jelly have an antibacterial effect, which may potentially overcome antibacterial resistance. However, in some cases, antibiotic tolerance can occur due to prolonged stress of low-dose antibacterial agents. This study aimed to investigate the effect of subinhibitory concentrations of royal jelly on bacterial growth, pyocyanin production, and biofilm formation of P. aeruginosa. Methods: Pseudomonas aeruginosa ATCC 10145 and clinical isolates were cultured in a royal jelly-containing medium to test the antibacterial activity. Pyocyanin production was observed by measuring the absorbance at 690 nm after 36 h culture and determined using extinction coefficient 4310 M-1 cm-1. Static microtiter plate biofilm assay performed to detect the biofilm formation, followed by scanning electron microscopy. Results: Royal jelly effectively inhibited the viability of both strains from a concentration of 25%. The highest production of pyocyanin was observed in the subinhibitory concentration group 6.25%, which gradually decreased along with the decrease of royal jelly concentration. Results of one-way ANOVA tests differed significantly in pyocyanin production of the two strains between the royal jelly groups. Tukey HSD test showed concentrations of 12.5%, 6.25%, and 3.125% significantly increased pyocyanin production of ATCC 10145, and the concentrations of 12.5% and 6.25% significantly increased production of the clinical isolates. Concentrations of 12.5% and 6.125% significantly induced biofilm formation of P. aeruginosa ATCC 10145, in line with the results of the SEM analysis. Conclusions: The royal jelly concentration of 25% or higher inhibits bacterial growth; however, the subinhibitory concentration increases pyocyanin production and biofilm formation in P. aeruginosa. It is advisable to determine the appropriate concentration of royal jelly to obtain beneficial virulence inhibiting activity.
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Amly, Dina Auliya, Puspita Hajardhini, Alma Linggar Jonarta, Heribertus Dedy Kusuma Yulianto, and Heni Susilowati. "Enhancement of pyocyanin production by subinhibitory concentration of royal jelly in Pseudomonas aeruginosa." F1000Research 10 (July 13, 2021): 14. http://dx.doi.org/10.12688/f1000research.27915.2.
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Background: Pseudomonas aeruginosa, a multidrug-resistant Gram-negative bacterium, produces pyocyanin, a virulence factor associated with antibiotic tolerance. High concentrations of royal jelly have an antibacterial effect, which may potentially overcome antibacterial resistance. However, in some cases, antibiotic tolerance can occur due to prolonged stress of low-dose antibacterial agents. This study aimed to investigate the effect of subinhibitory concentrations of royal jelly on bacterial growth, pyocyanin production, and biofilm formation of P. aeruginosa. Methods: Pseudomonas aeruginosa ATCC 10145 and clinical isolates were cultured in a royal jelly-containing medium to test the antibacterial activity. Pyocyanin production was observed by measuring the absorbance at 690 nm after 36 h culture and determined using extinction coefficient 4310 M-1 cm-1. Static microtiter plate biofilm assay performed to detect the biofilm formation, followed by scanning electron microscopy. Results: Royal jelly effectively inhibited the viability of both strains from a concentration of 25%. The highest production of pyocyanin was observed in the subinhibitory concentration group 6.25%, which gradually decreased along with the decrease of royal jelly concentration. Results of one-way ANOVA tests differed significantly in pyocyanin production of the two strains between the royal jelly groups. Tukey HSD test showed concentrations of 12.5%, 6.25%, and 3.125% significantly increased pyocyanin production of ATCC 10145, and the concentrations of 12.5% and 6.25% significantly increased production of the clinical isolates. Concentrations of 12.5% and 6.125% significantly induced biofilm formation of P. aeruginosa ATCC 10145, in line with the results of the SEM analysis. Conclusions: Royal jelly concentrations of 25% or higher can inhibit bacterial growth; however, subinhibitory concentrations could increase pyocyanin production and biofilm formation in P. aeruginosa. It is advisable to determine the appropriate concentration of royal jelly to obtain beneficial virulence inhibiting activity.
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Gonzalez, Claudio F., Anatoli Tchigvintsev, Greg Brown, Robert Flick, Elena Evdokimova, Xiaohui Xu, Jerzy Osipiuk, et al. "Structure and activity of the Pseudomonas aeruginosa hotdog-fold thioesterases PA5202 and PA2801." Biochemical Journal 444, no. 3 (May 29, 2012): 445–55. http://dx.doi.org/10.1042/bj20112032.
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The hotdog fold is one of the basic protein folds widely present in bacteria, archaea and eukaryotes. Many of these proteins exhibit thioesterase activity against fatty acyl-CoAs and play important roles in lipid metabolism, cellular signalling and degradation of xenobiotics. The genome of the opportunistic pathogen Pseudomonas aeruginosa contains over 20 genes encoding predicted hotdog-fold proteins, none of which have been experimentally characterized. We have found that two P. aeruginosa hotdog proteins display high thioesterase activity against 3-hydroxy-3-methylglutaryl-CoA and glutaryl-CoA (PA5202), and octanoyl-CoA (PA2801). Crystal structures of these proteins were solved (at 1.70 and 1.75 Å for PA5202 and PA2801 respectively) and revealed a hotdog fold with a potential catalytic carboxylate residue located on the long α-helix (Asp57 in PA5202 and Glu35 in PA2801). Alanine residue replacement mutagenesis of PA5202 identified four residues (Asn42, Arg43, Asp57 and Thr76) that are critical for its activity and are located in the active site. A P. aeruginosa PA5202 deletion strain showed an increased secretion of the antimicrobial pigment pyocyanine and an increased expression of genes involved in pyocyanin biosynthesis, suggesting a functional link between PA5202 activity and pyocyanin production. Thus the P. aeruginosa hotdog thioesterases PA5202 and PA2801 have similar structures, but exhibit different substrate preferences and functions.
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De Oliveira, Bianca Teixeira Morais, Kaíque Yago Gervazio De Lima, Ray Ravilly Alves Arruda, and Ulrich Vasconcelos. "Distinct stress responses to pyocyanin by planktonic and sessile Staphylococcus aureus UFPEDA 02 and Escherichia coli UFPEDA 224 / Respostas distintas ao estresse causado pela piocianina em células planctônicas e sésseis de Staphylococcus aureus UFPEDA 02 e Escherichia coli UFPEDA 224." Brazilian Journal of Development 7, no. 10 (October 18, 2021): 98074–88. http://dx.doi.org/10.34117/bjdv7n10-227.
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Antimicrobial activity of pyocyanin against competing organisms of Pseudomonas aeruginosa is related to the oxidative stress that the compound promotes in susceptible cells. The objective of this work was to produce, extract and verify the activity of pyocyanin in planktonic and sessile forms from clinical strains, Staphylococcus aureus UFPEDA 02 and Escherichia coli UFPEDA 224. About 600 µg/mL of pyocyanin were obtained. The planktonic cells were highly sensitive. The MIC determined for S. aureus UFPEDA 02 and E. coli UFPEDA 224 were 18.75 and 37.5 µg/mL, respectively. The pyocyanin demonstrated biocidal effect against S. aureus UFPEDA 02. On the other hand, pyocyanin was not active in either sessile strain. The presence of the pigment allowed a greater adherence of the strains, forming more robust biofilms compared to the control. S. aureus UFPEDA 02 and E. coli UFPEDA 224 presented moderate and high hydrophobicity, respectively. Glass and dolomite surfaces were tested in the in vitro biofilm test. Both strains formed the biofilm better on the dolomite surface, obtaining a cell concentration (MPN/cm2) in the order of 3 log units after 48h of incubation.
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Mavrodi, Dmitri V., Robert F. Bonsall, Shannon M. Delaney, Marilyn J. Soule, Greg Phillips, and Linda S. Thomashow. "Functional Analysis of Genes for Biosynthesis of Pyocyanin and Phenazine-1-Carboxamide from Pseudomonas aeruginosa PAO1." Journal of Bacteriology 183, no. 21 (November 1, 2001): 6454–65. http://dx.doi.org/10.1128/jb.183.21.6454-6465.2001.
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ABSTRACT Two seven-gene phenazine biosynthetic loci were cloned fromPseudomonas aeruginosa PAO1. The operons, designatedphzA1B1C1D1E1F1G1 and phzA2B2C2D2E2F2G2, are homologous to previously studied phenazine biosynthetic operons from Pseudomonas fluorescens and Pseudomonas aureofaciens. Functional studies of phenazine-nonproducing strains of fluorescent pseudomonads indicated that each of the biosynthetic operons from P. aeruginosa is sufficient for production of a single compound, phenazine-1-carboxylic acid (PCA). Subsequent conversion of PCA to pyocyanin is mediated in P. aeruginosa by two novel phenazine-modifying genes,phzM and phzS, which encode putative phenazine-specific methyltransferase and flavin-containing monooxygenase, respectively. Expression of phzS alone inEscherichia coli or in enzymes, pyocyanin-nonproducingP. fluorescens resulted in conversion of PCA to 1-hydroxyphenazine. P. aeruginosa with insertionally inactivated phzM or phzS developed pyocyanin-deficient phenotypes. A third phenazine-modifying gene,phzH, which has a homologue in Pseudomonas chlororaphis, also was identified and was shown to control synthesis of phenazine-1-carboxamide from PCA in P. aeruginosa PAO1. Our results suggest that there is a complex pyocyanin biosynthetic pathway in P. aeruginosaconsisting of two core loci responsible for synthesis of PCA and three additional genes encoding unique enzymes involved in the conversion of PCA to pyocyanin, 1-hydroxyphenazine, and phenazine-1-carboxamide.
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Polisetti, Sneha, Nameera F. Baig, Nydia Morales-Soto, Joshua D. Shrout, and Paul W. Bohn. "Spatial Mapping of Pyocyanin in Pseudomonas Aeruginosa Bacterial Communities Using Surface Enhanced Raman Scattering." Applied Spectroscopy 71, no. 2 (July 20, 2016): 215–23. http://dx.doi.org/10.1177/0003702816654167.
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Surface enhanced Raman spectroscopy (SERS) imaging was used in conjunction with principal component analysis (PCA) for the in situ spatiotemporal mapping of the virulence factor pyocyanin in communities of the pathogenic bacterium Pseudomonas aeruginosa. The combination of SERS imaging and PCA analysis provides a robust method for the characterization of heterogeneous biological systems while circumventing issues associated with interference from sample autofluorescence and low reproducibility of SERS signals. The production of pyocyanin is found to depend both on the growth carbon source and on the specific strain of P. aeruginosa studied. A cystic fibrosis lung isolate strain of P. aeruginosa synthesizes and secretes pyocyanin when grown with glucose and glutamate, while the laboratory strain exhibits detectable production of pyocyanin only when grown with glutamate as the source of carbon. Pyocyanin production in the laboratory strain grown with glucose was below the limit of detection of SERS. In addition, the combination of SERS imaging and PCA can elucidate subtle differences in the molecular composition of biofilms. PCA loading plots from the clinical isolate exhibit features corresponding to vibrational bands of carbohydrates, which represent the mucoid biofilm matrix specific to that isolate, features that are not seen in the PCA loading plots of the laboratory strain.
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Houshaymi, Bilal, Rana Awada, Mamdouh Kedees, and Zeina Soayfane. "Pyocyanin, a Metabolite of Pseudomonas Aeruginosa, Exhibits Antifungal Drug Activity Through Inhibition of a Pleiotropic Drug Resistance Subfamily FgABC3." Drug Research 69, no. 12 (June 28, 2019): 658–64. http://dx.doi.org/10.1055/a-0929-4380.
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AbstractThe fungus Fusarium graminearum is the causative agent of economically significant plant diseases such as Fusarium Healed Blight (FHB) of cereals, its mycotoxins as deoxynivalenol (DON), Nivalenol (NIV) and Zearalenone (ZEN) contaminate wheat and other grains. The objectives of the present study were to determine the mechanism by which the bacterium Pseudomonas aeruginosa inhibits the growth of F. graminearum. Our results indicate that P. aeruginosa metabolites as pyocyanin has effective antifungal properties. Pyocyanin was produced by P. aeruginosa when cultured on mineral salt medium and reached a maximum concentration after 72 h. Pyocyanin significantly decreased mycotoxins of F. graminearum, a 25 mg/ml of pyocyanin for 72 h decreased DON by 68.7% and NIV by 57.7%.Real-Time PCR analysis demonstrated that the antifungal effect is mediated by downregulation of the Pleiotropic Drug Resistance (PDR) subfamily FgABC3. 25 mg/ml of pyocyanin decreased FgABC3-mRNA by 60%, inhibited the fungal growth and decreased the area of mycelial growth at 12, 24, 36 and 72 h post incubation by 40–50%. Deletion of FgABC3 led to enhanced accumulation of DON and NIV by 40 and 60%, respectively.The data presented in this report may have significance in understanding mechanism by which certain bacterial metabolites exert a beneficial effect and for developing antifungal drugs.
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Munro, N. C., A. Barker, A. Rutman, G. Taylor, D. Watson, W. J. McDonald-Gibson, R. Towart, W. A. Taylor, R. Wilson, and P. J. Cole. "Effect of pyocyanin and 1-hydroxyphenazine on in vivo tracheal mucus velocity." Journal of Applied Physiology 67, no. 1 (July 1, 1989): 316–23. http://dx.doi.org/10.1152/jappl.1989.67.1.316.
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Products of the bacterium Pseudomonas aeruginosa have been shown to slow the beating of human respiratory tract cilia in vitro. We have tested the effects of two of these compounds, pyocyanin and 1-hydroxyphenazine (given as a bolus dose dissolved in 2 microliters Ringer solution), on tracheal mucus velocity of radiolabeled erythrocytes in anesthetized guinea pigs. 1-Hydroxyphenazine (200 ng) caused a rapid slowing of tracheal mucus velocity (maximum fall 47% at 20 min) with recovery by 1 h. The effect of pyocyanin was slower in onset, 600 ng causing 60% reduction in tracheal mucus velocity at 3 h, and no recovery occurred. A combination of pyocyanin and 1-hydroxyphenazine produced an initial rapid slowing equivalent to the same dose of 1-hydroxyphenazine given alone, but the later slowing attributed to pyocyanin was greater than the same dose administered alone. This study demonstrates one mechanism by which products of P. aeruginosa may facilitate its colonization of the respiratory tract.
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Narisawa, Naoki, Shin Haruta, Hiroyuki Arai, Masaharu Ishii, and Yasuo Igarashi. "Coexistence of Antibiotic-Producing and Antibiotic-Sensitive Bacteria in Biofilms Is Mediated by Resistant Bacteria." Applied and Environmental Microbiology 74, no. 12 (April 25, 2008): 3887–94. http://dx.doi.org/10.1128/aem.02497-07.
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ABSTRACT Antibiotic-sensitive bacteria have been found to coexist with antibiotic-producing bacteria in biofilms, but little is known about how the former develop in such an environment. Here we isolated pyocyanin-sensitive bacteria belonging to the genus Brevibacillus from a biofilm derived from soil extract and based on the preestablished biofilm of a pyocyanin producer, Pseudomonas aeruginosa strain P1. In addition, pyocyanin-resistant strains belonging to the genus Raoultella were isolated from the same biofilm. Microbial relationships within biofilms were examined by using three strains, strain P1, Brevibacillus strain S1, and Raoultella strain R1, each of which individually formed a biofilm within 2 days in a flow cell. Strain S1 did not fully develop on the preestablished biofilm of strain P1 during 4 days of cultivation, whereas a mutant of strain P1 which was deficient in pyocyanin production allowed strain S1 to cocolonize within a biofilm. On the other hand, strain R1 developed on the biofilm of strain P1 regardless of pyocyanin production. When mixed 1:1 inocula of strains S1 and R1 were introduced into the strain P1 biofilm, all three species were found in the 4-day biofilm. In the mixed biofilm, strain S1 was surrounded by the layer of strain R1 and seemed to be separated from strain P1 and the outflow solution. However, strain S1 did not survive in a three-species mixed culture under planktonic conditions. These results indicate that the survival of sensitive bacteria in biofilm with a pyocyanin producer is achieved by covering them with a layer of resistant bacteria. We also evaluated the influence of antibiotic production on the producer.
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Naik, Varsha, and Girish Mahajan. "Quorum Sensing: A Non-conventional Target for Antibiotic Discovery." Natural Product Communications 8, no. 10 (October 2013): 1934578X1300801. http://dx.doi.org/10.1177/1934578x1300801030.
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Quorum sensing (QS) is known to regulate different functions viz. pathogenesis, biofilm formation, and host colonization, along with other functions by regulating bacterial virulence determinants. Therefore, QS is deemed to be an interesting target to modulate pathogenesis. Also, there have been global reports of continuous emergence of antibiotic-resistant microbes; hence, an alternative treatment that compliments antibiotic activity is highly desirable. One such approach is to look for QS inhibitors, which can quench the virulence phenotypes exerted by pathogenic bacteria and compliment antibiotic treatment. In the present study, Pseudomonas aeruginosa strain was used as the model organism which produces three pigments viz. pyocyanin, pyoverdin and pyorubin. Pyocyanin synthesis is reported to be QS dependent and is one of the virulence factors of P. aeruginosa. Hence, we envisage inhibition of pyocyanin pigment would indicate QS inhibition (QSI). Auto-inducers like N-(3-oxododecanoyl)-L-homoserine lactone (OdDHL/3-oxo-C12-HSL) and N-butyryl-L- homoserine lactone (BHL/C4-HSL) were used to enhance the pyocyanin pigment production by the model strain at different doses and time points. BHL, at 25 μM was found to be a better inducer of pyocyanin. Tannic acid (TA) was tested to suppress this pigment synthesis and it was found to be effective when assessed at different time points. About 5.12 mg/mL TA was found to be the optimum concentration at which pyocyanin was inhibited by 77.3%. Thus, we confirm that TA can be used as a QSI, either in its purest form or in the crude form found in various plant species, and could be considered for development to compliment antibiotic therapy.
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Huang, Jiaofang, Elisabeth Sonnleitner, Bin Ren, Yuquan Xu, and Dieter Haas. "Catabolite Repression Control of Pyocyanin Biosynthesis at an Intersection of Primary and Secondary Metabolism in Pseudomonas aeruginosa." Applied and Environmental Microbiology 78, no. 14 (May 4, 2012): 5016–20. http://dx.doi.org/10.1128/aem.00026-12.
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ABSTRACTInPseudomonas aeruginosa, the catabolite repression control (Crc) protein repressed the formation of the blue pigment pyocyanin in response to a preferred carbon source (succinate) by interacting withphzMmRNA, which encodes a key enzyme in pyocyanin biosynthesis. Crc bound to an extended imperfect recognition sequence that was interrupted by the AUG translation initiation codon.
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Mojsoska, Biljana, Melanie Ghoul, Gabriel G. Perron, Håvard Jenssen, and Fatima AlZahra’a Alatraktchi. "Changes in toxin production of environmental Pseudomonas aeruginosa isolates exposed to sub-inhibitory concentrations of three common antibiotics." PLOS ONE 16, no. 3 (March 4, 2021): e0248014. http://dx.doi.org/10.1371/journal.pone.0248014.
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Pseudomonas aeruginosa is an environmental pathogen that can cause severe infections in immunocompromised patients. P. aeruginosa infections are typically treated with multiple antibiotics including tobramycin, ciprofloxacin, and meropenem. However, antibiotics do not always entirely clear the bacteria from the infection site, where they may remain virulent. This is because the effective antibiotic concentration and diffusion in vitro may differ from the in vivo environment in patients. Therefore, it is important to understand the effect of non-lethal sub-inhibitory antibiotic concentrations on bacterial phenotype. Here, we investigate if sub-inhibitory antimicrobial concentrations cause alterations in bacterial virulence factor production using pyocyanin as a model toxin. We tested this using the aforementioned antibiotics on 10 environmental P. aeruginosa strains. Using on-the-spot electrochemical screening, we were able to directly quantify changes in production of pyocyanin in a measurement time of 17 seconds. Upon selecting 3 representative strains to further test the effects of sub-minimum inhibitory concentration (MICs), we found that pyocyanin production changed significantly when the bacteria were exposed to 10-fold MIC of the 3 antibiotics tested, and this was strain specific. A series of biologically relevant measured pyocyanin concentrations were also used to assess the effects of increased virulence on a culture of epithelial cells. We found a decreased viability of the epithelial cells when incubated with biologically relevant pyocyanin concentrations. This suggests that the antibiotic-induced virulence also is a value worth being enclosed in regular testing of pathogens.
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Petrovic, Snjezana, Jasmina Basic, Zoran Mandinic, Dragana Bozic, Marina Milenkovic, and Zorica Vujic. "Inhibitory effect of propafenone derivatives on pseudomonas aeruginosa biofilm and pyocyanin production." Srpski arhiv za celokupno lekarstvo 148, no. 3-4 (2020): 196–202. http://dx.doi.org/10.2298/sarh180727102p.
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Introduction/Objective. Biofilm and pyocyanin production are essential components of Pseudomonas aeruginosa virulence and antibiotic resistance. Our objective was to examine inhibitory effect of synthetized propafenone derivatives 3-(2-Fluorophenyl)- 1-(2- (2-hydroxy-3-propylamino-propoxy)-phenyl)-propan-1-one hydrochloride (5OF) and3-(2- Trifluoromethyl-phenyl)-1-(2-(2-hydroxy-3-propylamino-propoxy)-phenyl)-propan-1-one hydrochloride (5CF3) on biofilm and pyocyanin in Pseudomonas aeruginosa clinical strains. Methods. Effects were tested on nine clinical isolates and one control laboratory strain of P. aeruginosa. In vitro analysis of biofilm growing was performed by incubating bacteria (0.5 McFarland) with 5OF and 5CF3 (500?31.2 ?g/ml) and measuring optical density (OD) at 570 nm. Bacteria in medium without compounds were positive control. Blank medium (an uninoculated medium without test compounds) was used as negative control. Pyocyanin production was estimated by OD at 520 nm, after bacteria incubated with 5CF3 and 5OF (250 and 500 ?g/ml), treated with chloroform, and chloroform layer mixed with HCl. Results. A total of 500 ?g/ml of 5OF and 5CF3 completely inhibited biofilm formation in 10/10 and 4/10 strains, respectively. A total of 250 ?g/ml of 5OF and 5CF3 strongly inhibited biofilm formation in 7/10 strains, while inhibition with 125 ?g/ml of 5OF and 5CF3 was moderate. Lower concentrations had almost no effect on biofilm production. Pyocyanin production was reduced to less than 40% of the control value in 6/9, and less than 50% of the control in 7/9 strains with 500 ?g/ml of 5OF and 5CF3, respectively. At 250 ?g/ml 5OF and 5CF3, most strains had pyocyanin production above 50% of the control value. Conclusion. Synthetized propafenone derivatives, 5OF and 5CF3, inhibited biofilms and pyocyanin production of Pseudomonas aeruginosa clinical strains. Presented results suggest that propafenone derivatives are potential lead-compounds for synthesis of novel antipseudomonal drugs.
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Vinckx, Tiffany, Qing Wei, Sandra Matthijs, and Pierre Cornelis. "The Pseudomonas aeruginosa oxidative stress regulator OxyR influences production of pyocyanin and rhamnolipids: protective role of pyocyanin." Microbiology 156, no. 3 (March 1, 2010): 678–86. http://dx.doi.org/10.1099/mic.0.031971-0.
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The LysR-type transcriptional regulator (LTTR) OxyR orchestrates the defence of the opportunistic pathogen Pseudomonas aeruginosa against reactive oxygen species. In previous work we also demonstrated that OxyR is needed for the utilization of the ferrisiderophore pyoverdine, stressing the importance of this regulator. Here, we show that an oxyR mutant is unable to swarm on agar plates, probably as a consequence of absence of production of rhamnolipid surfactant molecules. Another obvious phenotypic change was the increased production of the phenazine redox-active molecule pyocyanin in the oxyR mutant. As already described, the oxyR mutant could not grow in LB medium, unless high numbers of cells (>108 ml−1) were inoculated. However, its growth in Pseudomonas P agar (King's A), a medium inducing pyocyanin production, was like that of the wild-type, suggesting a protective action of this redox-active phenazine compound. This was confirmed by the restoration of the capacity to grow in LB medium upon addition of pure pyocyanin. Although both rhamnolipid and pyocyanin production are controlled by quorum sensing, no obvious changes were observed in the production of N-acylhomoserine lactones or the Pseudomonas quinolone signal (PQS). Complementation of rhamnolipid production and motility, and restoration of normal pyocyanin levels, was only possible when the oxyR gene was in single copy, while pyocyanin levels were increased when oxyR was present in a multicopy vector. Conversely, plating efficiency was increased only when the oxyR gene was present in multicopy, but not when in single copy in the chromosome, due to lower expression of oxyR compared with the wild-type, suggesting that some phenotypes are differently affected in function to the levels of OxyR molecules in the cell. Analysis of transcripts of oxidative stress-response enzymes showed a strong decrease of katB, ahpC and ahpB expression in the oxyR mutant grown in LB, but this was not the case when the mutant was grown on P agar, suggesting that the OxyR dependency for the transcription of these genes is not total.
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Horke, Sven, Ines Witte, Sebastian Altenhöfer, Petra Wilgenbus, Marion Goldeck, Ulrich Förstermann, Junhui Xiao, et al. "Paraoxonase 2 is down-regulated by the Pseudomonas aeruginosa quorumsensing signal N-(3-oxododecanoyl)-L-homoserine lactone and attenuates oxidative stress induced by pyocyanin." Biochemical Journal 426, no. 1 (January 27, 2010): 73–83. http://dx.doi.org/10.1042/bj20091414.
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Two virulence factors produced by Pseudomonas aeruginosa are pyocyanin and N-(3-oxododecanoyl)-L-homoserine lactone (3OC12). Pyocyanin damages host cells by generating ROS (reactive oxygen species). 3OC12 is a quorum-sensing signalling molecule which regulates bacterial gene expression and modulates host immune responses. PON2 (paraoxonase-2) is an esterase that inactivates 3OC12 and potentially attenuates Ps. aeruginosa virulence. Because increased intracellular Ca2+ initiates the degradation of PON2 mRNA and protein and 3OC12 causes increases in cytosolic Ca2+, we hypothesized that 3OC12 would also down-regulate PON2. 3OC12 and the Ca2+ ionophore A23187 caused a rapid cytosolic Ca2+ influx and down-regulated PON2 mRNA, protein and hydrolytic activity in A549 and EA.hy 926 cells. The decrease in PON2 hydrolytic activity was much more extensive and rapid than decreases in protein, suggesting a rapid post-translational mechanism which blocks PON2's hydrolytic activity. The Ca2+ chelator BAPTA/AM [1,2-bis-(o-aminophenoxy)ethane-N,N,N′,N′-tetra-acetic acid tetrakis(acetoxymethyl ester)] diminished the ability of 3OC12 to decrease PON2, demonstrating that the effects are mediated by Ca2+. PON2 also has antioxidative properties and we show that it protects cells from pyocyanin-induced oxidative stress. Knockdown of PON2 by transfecting cells with siRNA (small interfering RNA) rendered them more sensitive to, whereas overexpression of PON2 protected cells from, pyocyanin-induced ROS formation. Additionally, 3OC12 potentiated pyocyanin-induced ROS formation, presumably by inactivating PON2. These findings support a key role for PON2 in the defence against Ps. aeruginosa virulence, but also reveal a mechanism by which the bacterium may subvert the protection afforded by PON2.
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Yan, Rong, Shikun Hu, Ning Ma, Peiqing Song, Qingqing Liang, Huiqun Zhang, Yanqi Li, Lixin Shen, Kangmin Duan, and Lin Chen. "Regulatory Effect of DNA Topoisomerase I on T3SS Activity, Antibiotic Susceptibility and Quorum- Sensing-Independent Pyocyanin Synthesis in Pseudomonas aeruginosa." International Journal of Molecular Sciences 20, no. 5 (March 5, 2019): 1116. http://dx.doi.org/10.3390/ijms20051116.
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Topoisomerases are required for alleviating supercoiling of DNA during transcription and replication. Recent evidence suggests that supercoiling of bacterial DNA can affect bacterial pathogenicity. To understand the potential regulatory role of a topoisomerase I (TopA) in Pseudomonas aeruginosa, we investigated a previously isolated topA mutation using genetic approaches. We here report the effects of the altered topoisomerase in P. aeruginosa on type III secretion system, antibiotic susceptibility, biofilm initiation, and pyocyanin production. We found that topA was essential in P. aeruginosa, but a transposon mutant lacking the 13 amino acid residues at the C-terminal of the TopA and a mutant, named topA-RM, in which topA was split into three fragments were viable. The reduced T3SS expression in topA-RM seemed to be directly related to TopA functionality, but not to DNA supercoiling. The drastically increased pyocyanin production in the mutant was a result of up-regulation of the pyocyanin related genes, and the regulation was mediated through the transcriptional regulator PrtN, which is known to regulate bacteriocin. The well-established regulatory pathway, quorum sensing, was unexpectedly not involved in the increased pyocyanin synthesis. Our results demonstrated the unique roles of TopA in T3SS activity, antibiotic susceptibility, initial biofilm formation, and secondary metabolite production, and revealed previously unknown regulatory pathways.
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Quang Vinh, Nguyen, Nguyen Hoang Uyen, Nguyen Chi Thuan, and Nguyen Thi Thanh Loi. "Increased production of pyocyanin in recombinant Pseudomonas aeruginosa PS39-phzMS strain harboring the pUCP24-phzMS plasmid." Vietnam Journal of Biotechnology 20, no. 1 (June 9, 2022): 135–42. http://dx.doi.org/10.15625/1811-4989/16154.
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PhzM and PhzS are two “core” enzymes that are necessary for conversion of phenazine-1-carboxylic acid (PCA) into pyocyanin (PYO) phenazine in Gram (-) bacterium Pseudomonas aeruginosa. Apparently, the raise in copy number of their genes could increase the amount of pyocyanin phenazine in the microbe. In previous research, two genes phzM and phzS originated from Pseudomonas aeruginosa PS39 strain had been inserted into a Pseudomonas – Escherichia coli shutlle vector pUCP24 to generate a plasmid pUCP24-phzMS. The obtained plasmid had been transformed into P. aeruginosa PS39 strain to create the recombinant P. aeruginosa PS39-phzMS strain. In this study, pUCP24-phzMS was sequenced to verify the polycistronic expression cassette containing both phzM and phzS genes. The results demonstrated that the recombinant plasmid comprised the ori of Pseudomonas and E. coli, gentamicin resistance-cassette, and polycistronic expression cassette for expression of PhzM and PhzS. In which, both genes will be transcripted together in one mRNA strand by the regulation of Lac promoter and operator. The translation from the mRNA to the corresponding proteins will be started by binding ribosome into RBS located upstream of each gene. The nucleotide sequence of these genes were completely homologous (100%) to the submitted sequences MF673740 (phzM) and MF770713 (phzS) on the NCBI GenBank database. Result on assessing the synthesis of pyocyanin in the recombinant strain with the presence of pUCP24-phzMS plasmid showed that pyocyanin concentration in the recombinant strain increased significantly over 2 times (31.22 mg/mL) more than that in the wild strain (13.47 mg/mL). The absorbance at 360 nm of PCA from the P. aeruginosa PS39-phzMS (OD367 = 0.03) strain decreased significantly compared to the one from wild type strain (OD367 = 0.39). Therefore, the plasmid with phzM and phzS genes was proved to improve the pyocyanin biosynthesis through a better conversion of PCA phenazine into PYO via PhzM and PhzS enzymes.
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Peng, Wenjing, Hui Li, Xiaole Zhao, Bing Shao, and Kui Zhu. "Pyocyanin Modulates Gastrointestinal Transformation and Microbiota." Journal of Agricultural and Food Chemistry 70, no. 8 (February 16, 2022): 2722–32. http://dx.doi.org/10.1021/acs.jafc.1c07726.
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Ran, H., D. J. Hassett, and G. W. Lau. "Human targets of Pseudomonas aeruginosa pyocyanin." Proceedings of the National Academy of Sciences 100, no. 24 (November 6, 2003): 14315–20. http://dx.doi.org/10.1073/pnas.2332354100.
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El-Fouly, M. Z., A. M. Sharaf, A. A. M. Shahin, Heba A. El-Bialy, and A. M. A. Omara. "Biosynthesis of pyocyanin pigment byPseudomonas aeruginosa." Journal of Radiation Research and Applied Sciences 8, no. 1 (January 2015): 36–48. http://dx.doi.org/10.1016/j.jrras.2014.10.007.
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Cheluvappa, Rajkumar, and Rajaraman Eri. "Conjugate products of pyocyanin–glutathione reactions." Chemico-Biological Interactions 238 (August 2015): 91–92. http://dx.doi.org/10.1016/j.cbi.2015.06.002.
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Grace Vergara Padilla, Krystel, and King Dave Gloria Martin. "Quantifying Production of Quorum Sensing Regulated Pigments in Pseudomonas aeruginosa BIOTECH 1335." Oriental Journal Of Chemistry 36, no. 05 (October 25, 2020): 934–39. http://dx.doi.org/10.13005/ojc/360519.
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One more method that can be used in the fight against communicable diseases is greatly important. Numerous pathogenic bacteria use intercellular signaling known as quorum sensing (QS) in defining virulence gene expression as well as gene regulatory mechanisms. Among the most promising sources of QSI agents are the ethnobotanicals. Extraction used 95% n-hexane in ethnobotanical leaves of A. triplinervis, B. pilosa, C. nocturnum, S. glabra, P. pentandrum, O. trinervis, D. elliptica, A. scholaris, A. adenophora, and Lipang daga (no scientific name). Extracts that were negative in the antibacterial testing proceeded to the QSI assay for pyocyanin production. The ten ethnobotanical extracts did not exhibit antibacterial activity against P. aeruginosa and were found to increase the pyocyanin production therefore the absence of QSI. However, all plant extracts can be used to increase the production of pyocyanin to accumulate more metabolites that are proven to have important biological and biotechnological applications.
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Abd El-Aziz, Norhan Khairy, Marwa Ibrahim Abd El-Hamid, and El-sayed Youssef El-Naenaeey. "A complex hierarchical quorum-sensing circuitry modulates phenazine gene expression in Pseudomonas aeruginosa." Journal of Infection in Developing Countries 11, no. 12 (January 10, 2018): 919–25. http://dx.doi.org/10.3855/jidc.8775.
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Introduction: Pseudomonas aeruginosa (P. aeruginosa) modulates the expression of a myriad of virulence factors via two complicated hierarchical quorum-sensing (QS) cascade. This study shed light on the interrelation between P. aeruginosa QS systems and pyocyanin production.
Methodology: Transcription analysis of lasR, rhlR, rhlI and phz genes using quantitative real time-reverse transcriptase PCR (qRT–PCR) assay, followed by sequencing of the autoinducer synthase (lasI gene) were applied for 15 P. aeruginosa strains recovered from diverse animal clinical sources.
Results: Expression studies revealed that most P. aeruginosa strains demonstrated statistically significant differences (p < 0.05) with a very wide range of transcript levels of QS and phz genes in comparison to P. aeruginosa ATCC 27853. We have identified significant positive correlations (r ≥ 0.3) between the expressions of QS and phz genes in eleven analyzed strains, whereas pyocyanin production positively correlated with the expression of lasR only in three strains (r ≥ 0.6). We further found that there was a negative correlation between the transcript levels of QS and phz genes in one bacterial strain. Analysis of lasI sequences showed point mutations explaining the alterations in pyocyanin expression. The deficiencies of lasI, lasR and rhlI with rhlR-dependent expression of phz in one strain were also recorded.
Conclusions: These results provided new insights to the pivotal role of QS signal molecules on pyocyanin production presenting the las system as the dominant regulator.
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Bhargava, Nidhi, Prince Sharma, and Neena Capalash. "Pyocyanin Stimulates Quorum Sensing-Mediated Tolerance to Oxidative Stress and Increases Persister Cell Populations in Acinetobacter baumannii." Infection and Immunity 82, no. 8 (June 2, 2014): 3417–25. http://dx.doi.org/10.1128/iai.01600-14.
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ABSTRACTAcinetobacter baumanniiandPseudomonas aeruginosaare nosocomial pathogens with overlapping sites of infection. This work reports that the two can coexist stably in mixed-culture biofilms. In a study intended to improve our understanding of the mechanism of their coexistence, it was found that pyocyanin, produced byP. aeruginosathat generally eliminates competition from other pathogens, led to the generation of reactive oxygen species (ROS) inA. baumanniicells, which in response showed a significant (P≤ 0.05) increase in production of enzymes, specifically, catalase and superoxide dismutase (SOD). This work shows for the first time that the expression of catalase and SOD is under the control of a quorum-sensing system inA. baumannii. In support of this observation, a quorum-sensing mutant ofA. baumannii(abaI::Km) was found to be sensitive to pyocyanin compared to its wild type and showed significantly (P≤ 0.001) lower levels of the antioxidant enzymes, which increased on addition of 5 μMN-(3-hydroxydodecanoyl)-l-homoserine lactone. Likewise, in wild-typeA. baumannii, there was a significant (P< 0.01) decrease in the level of anti-oxidant enzymes in the presence of salicylic acid, a known quencher of quorum sensing. In the presence of amikacin and carbenicillin,A. baumanniiformed 0.07 and 0.02% persister cells, which increased 4- and 3-fold, respectively, in the presence of pyocyanin. These findings show that pyocyanin induces a protective mechanism inA. baumanniiagainst oxidative stress and also increases its persistence against antibiotics which could be of clinical significance in the case of coinfections withA. baumanniiandP. aeruginosa.
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Sharma, Chandni, Ashish K. Shukla, and Amitabha Acharya. "Rational design of a FRET-based nanoprobe of gold-conjugated carbon dots for simultaneous monitoring and disruption of Pseudomonas aeruginosa biofilm through selective detection of virulence factor pyocyanin." Environmental Science: Nano 8, no. 6 (2021): 1713–28. http://dx.doi.org/10.1039/d1en00187f.
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Al-Haidari, Rwaida A., Mona I. Shaaban, Sabrin R. M. Ibrahim, and Gamal A. Mohamed. "ANTI-QUORUM SENSING ACTIVITY OF SOME MEDICINAL PLANTS." African Journal of Traditional, Complementary and Alternative Medicines 13, no. 5 (August 12, 2016): 67–71. http://dx.doi.org/10.21010/ajtcam.v13i5.10.
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Background: Quorum sensing is the key regulator of virulence factors of Pseudomonas aeruginosa such as biofilm formation, motility, productions of proteases, hemolysin, pyocyanin, and toxins.
Material and Methods: Quorum sensing inhibitory (OSI) effect of the alcohol extracts of 20 medicinal plants was evaluated by Chromobacterium violaceum reporter using agar cup diffusion method. The efficient QSI extracts were tested for their activity against biofilm synthesis, motility, and synthesis of pyocyanin from P. aeruginosa PA14
Results: The extracts of Citrus sinensis, Laurus nobilis, Elettaria cardamomum, Allium cepa, and Coriandrum sativum exhibited potent quorum quenching effect. On the other hand, Psidium guajava and Mentha longifolia extracts showed lower QSI activity. These extracts exhibited significant elimination of pyocyanin formation and biofilm development of Pseudomonas aeruginosa PA14. In addition, they significantly inhibited twitching and swimming motilities of P. aeruginosa PA14.
Conclusion: This study illustrated for the first time the importance of C. sinensis, L. nobilis, E. cardamomum, A. cepa, and C. sativum as quorum sensing inhibitors and virulence suppressors of P. aeruginosa.