keyword
MENU ▼
Read by QxMD icon Read
search

pyocyanin

keyword
https://www.readbyqxmd.com/read/29130161/detection-of-2-alkyl-4-quinolones-using-biosensors
#1
Matthew P Fletcher, Stephen P Diggle, Miguel Cámara, Paul Williams
2-Alkyl-4-quinolones (AQs) such as 2-heptyl-3-hydroxy-4-quinolone (PQS) and 2-heptyl-4-hydroxyquinoline (HHQ) are quorum-sensing signal molecules. Here we describe two methods for AQ detection and quantification that employ thin-layer chromatography (TLC) and microtiter plate assays in combination with a lux-based Pseudomonas aeruginosa AQ biosensor strain. For TLC detection, organic solvent extracts of bacterial cells or spent culture supernatants are chromatographed on TLC plates, which are then dried and overlaid with the AQ biosensor...
2018: Methods in Molecular Biology
https://www.readbyqxmd.com/read/29115136/kinetic-control-of-quorum-sensing-in-pseudomonas-aeruginosa-by-multidrug-efflux-pumps
#2
David Wolloscheck, Ganesh Krishnamoorthy, Jennifer Nguyen, Helen I Zgurskaya
Pseudomonas aeruginosa is an important human pathogen, the physiology and virulence of which are under the control of quorum sensing signals. These signals often have dual roles, functioning as toxins to some cells and as oxidative-stress protectors for their producer cells. Hence, their internal and external concentrations should be tightly controlled. In this study, we analyzed the interplay between the multidrug efflux transporters MexEF-OprN and MexG/HI-OpmD in quorum sensing of P. aeruginosa. We found that the two transporters have overlapping substrate specificities but different efficiencies...
November 8, 2017: ACS Infectious Diseases
https://www.readbyqxmd.com/read/29090193/reduced-intracellular-c-di-gmp-content-increases-expression-of-quorum-sensing-regulated-genes-in-pseudomonas-aeruginosa
#3
Song Lin Chua, Yang Liu, Yingying Li, Hui Jun Ting, Gurjeet S Kohli, Zhao Cai, Pipob Suwanchaikasem, Kelvin Kau Kit Goh, Sean Pin Ng, Tim Tolker-Nielsen, Liang Yang, Michael Givskov
Cyclic-di-GMP (c-di-GMP) is an intracellular secondary messenger which controls the biofilm life cycle in many bacterial species. High intracellular c-di-GMP content enhances biofilm formation via the reduction of motility and production of biofilm matrix, while low c-di-GMP content in biofilm cells leads to increased motility and biofilm dispersal. While the effect of high c-di-GMP levels on bacterial lifestyles is well studied, the physiology of cells at low c-di-GMP levels remains unclear. Here, we showed that Pseudomonas aeruginosa cells with high and low intracellular c-di-GMP contents possessed distinct transcriptome profiles...
2017: Frontiers in Cellular and Infection Microbiology
https://www.readbyqxmd.com/read/29089927/autoinducer-2-facilitates-pseudomonas-aeruginosa-pao1-pathogenicity-in-vitro-and-in-vivo
#4
Hongdong Li, Xingyuan Li, Chao Song, Yunhui Zhang, Zhengli Wang, Zhenqiu Liu, Hong Wei, Jialin Yu
Bacterial communication systems, such as quorum sensing (QS), have provided new insights of alternative approaches in antimicrobial treatment. We recently reported that one QS signal, named as autoinducer-2 (AI-2), can affect the behaviors of Pseudomonas aeruginosa PAO1 in a dose-dependent manner. In this study, we aimed to investigate the effects of AI-2 on P. aeruginosa PAO1 biofilm formation and virulence factors production in vitro, and in vivo using a pulmonary infection mouse model. Exogenous AI-2 resulted in increased biofilms architecture, the number of viable cells, and the yield of pyocyanin and elastase virulence factors in wild type P...
2017: Frontiers in Microbiology
https://www.readbyqxmd.com/read/29042302/attenuation-of-pseudomonas-aeruginosa-quorum-sensing-virulence-and-biofilm-formation-by-extracts-of-andrographis-paniculata
#5
Malabika Banerjee, Soumitra Moulick, Kunal Kumar Bhattacharya, Debaprasad Parai, Subrata Chattopadhyay, Samir Kumar Mukherjee
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...
October 14, 2017: Microbial Pathogenesis
https://www.readbyqxmd.com/read/29038052/serine-threonine-protein-kinase-ppka-contributes-to-the-adaptation-and-virulence-in-pseudomonas-aeruginosa
#6
Jianyi Pan, Zhenzhong Zha, Pengfei Zhang, Ran Chen, Chen Ye, Ting Ye
Pseudomonas aeruginosa is a leading cause of nosocomial infections worldwide and has become a serious public health threat, which is attributed to a large extent to its extraordinary environmental adaptability and diverse virulence factors that result in infection and progression of pathogenesis. The eukaryote-type serine/threonine (Ser/Thr) protein kinases, known for playing major regulatory roles in eukaryotes, have been demonstrated to play a central role in regulating various bacterial cellular processes via catalyzing protein phosphorylation...
October 13, 2017: Microbial Pathogenesis
https://www.readbyqxmd.com/read/29026394/quorum-sensing-inhibitory-activity-of-sub-inhibitory-concentrations-of-%C3%AE-lactams
#7
Somaia A El-Mowafy, Khaled H Abd El Galil, El-Sayed E Habib, Mona I Shaaban
INTRODUCTION: The virulence factors of Pseudomonas aeruginosa are under the control of quorum sensing (QS) signals. Hence, interference with QS prevents its pathogenesis. OBJECTIVE: The aim of the present research is to assess the influence of some β-lactam antibiotics on cell communication and the release of different virulence factors. METHODS: The minimal inhibitory concentrations of ceftazidime, cefepime and imipenem were evaluated by microbroth dilution method...
March 2017: African Health Sciences
https://www.readbyqxmd.com/read/29018437/biocontrol-of-bacterial-leaf-blight-of-rice-and-profiling-of-secondary-metabolites-produced-by-rhizospheric-pseudomonas-aeruginosa-brp3
#8
Sumera Yasmin, Fauzia Y Hafeez, Muhammad S Mirza, Maria Rasul, Hafiz M I Arshad, Muhammad Zubair, Mazhar Iqbal
Xanthomonas oryzae pv. oryzae (Xoo) is widely prevalent and causes Bacterial Leaf Blight (BLB) in Basmati rice grown in different areas of Pakistan. There is a need to use environmentally safe approaches to overcome the loss of grain yield in rice due to this disease. The present study aimed to develop inocula, based on native antagonistic bacteria for biocontrol of BLB and to increase the yield of Super Basmati rice variety. Out of 512 bacteria isolated from the rice rhizosphere and screened for plant growth promoting determinants, the isolate BRp3 was found to be the best as it solubilized 97 μg/ mL phosphorus, produced 30 μg/mL phytohormone indole acetic acid and 15 mg/ L siderophores in vitro...
2017: Frontiers in Microbiology
https://www.readbyqxmd.com/read/28993916/antimicrobial-metabolites-from-saraca-asoca-impairs-the-membrane-transport-system-and-quorum-sensing-system-in-pseudomonas-aeruginosa
#9
Preeti Jain, Amit Nale, Rajesh Dabur
This study was conducted to explore the antimicrobial mechanism of metabolites from Saraca asoca (SA1) using differential proteomics and metabolic profile of Pseudomonas aeruginosa after treatment with effective sub-MIC dose of 312 µg/mL. SA1 fraction was found to contain antibacterial metabolites catechol, protocatechuic acid, and epigallocatechin gallate. Proteome analysis revealed 33 differentially expressed proteins after SA1 treatment. Protein network analysis showed that SA1 treatment upregulated the DNA topological and metabolic processes...
October 9, 2017: Archives of Microbiology
https://www.readbyqxmd.com/read/28983655/mechanistic-understanding-of-phenyllactic-acid-mediated-inhibition-of-quorum-sensing-and-biofilm-development-in-pseudomonas-aeruginosa
#10
Maitrayee Chatterjee, Sharon D'Morris, Vinod Paul, Sruthi Warrier, Anil Kumar Vasudevan, Muralidharan Vanuopadath, Sudarslal Sadasivan Nair, Bindhu Paul-Prasanth, C Gopi Mohan, Raja Biswas
Pseudomonas aeruginosa depends on its quorum sensing (QS) system for its virulence factors' production and biofilm formation. Biofilms of P. aeruginosa on the surface of indwelling catheters are often resistant to antibiotic therapy. Alternative approaches that employ QS inhibitors alone or in combination with antibiotics are being developed to tackle P. aeruginosa infections. Here, we have studied the mechanism of action of 3-Phenyllactic acid (PLA), a QS inhibitory compound produced by Lactobacillus species, against P...
October 5, 2017: Applied Microbiology and Biotechnology
https://www.readbyqxmd.com/read/28974743/targeting-the-alternative-sigma-factor-rpon-to-combat-virulence-in-pseudomonas-aeruginosa
#11
Megan G Lloyd, Benjamin R Lundgren, Clayton W Hall, Luke B-P Gagnon, Thien-Fah Mah, Jennifer F Moffat, Christopher T Nomura
Pseudomonas aeruginosa is a Gram-negative, opportunistic pathogen that infects immunocompromised and cystic fibrosis patients. Treatment is difficult due to antibiotic resistance, and new antimicrobials are needed to treat infections. The alternative sigma factor 54 (σ(54), RpoN), regulates many virulence-associated genes. Thus, we evaluated inhibition of virulence in P. aeruginosa by a designed peptide (RpoN molecular roadblock, RpoN*) which binds specifically to RpoN consensus promoters. We expected that RpoN* binding to its consensus promoter sites would repress gene expression and thus virulence by blocking RpoN and/or other transcription factors...
October 3, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28961860/effect-of-bacterial-components-of-mixed-culture-supernatants-of-planktonic-and-biofilm-pseudomonas-aeruginosa-with-commensal-escherichia-coli-on-the-neutrophil-response-in-vitro
#12
I L Maslennikova, M V Kuznetsova, I V Nekrasova, S V Shirshev
Pseudomonas aeruginosa (PA) responsible for acute and chronic infections often forms a well-organized bacterial population with different microbial species including commensal strains of Escherichia coli. Bacterial extracellular components of mixed culture can modulate the influence of bacteria on the neutrophil functions. The objective of this study was to compare the effect of pyocyanin, pyoverdine, LPS, exopolysaccharide of single species and mixed culture supernatants of PA strains and E. coli K12 on microbicidal, secretory activity of human neutrophils in vitro...
August 31, 2017: Pathogens and Disease
https://www.readbyqxmd.com/read/28939255/inhibition-of-quorum-sensing-related-virulence-factors-of-pseudomonas-aeruginosa-by-pyridoxal-lactohydrazone
#13
Azam Heidari, Nader Noshiranzadeh, Fakhri Haghi, Rahman Bikas
Pseudomonas aeruginosa quorum sensing (QS) system is a cell to cell signaling mechanism that regulates virulence factors and pathogenicity. Therefore, the QS system in P. aeruginosa may be an important target for pharmacological intervention. The present study aimed to investigate the effects of sub-MIC concentrations of (S,E)-2-hydroxy-N-(3-hydroxy-5-(hydroxymethyl)-2-methylpyridin-4-yl)propane hydrazide (pyridoxal lactohydrazone) against P. aeruginosa QS related virulence factors. We investigated the effect of sub-MIC concentrations of chiral pyridoxal lactohydrazone, which formed by the reaction of chiral lactic acid hydrazide and pyridoxal (one form of Vitamin B6) as bioactive reagents, on virulence factors...
September 20, 2017: Microbial Pathogenesis
https://www.readbyqxmd.com/read/28931063/plant-flavones-enhance-antimicrobial-activity-of-respiratory-epithelial-cell-secretions-against-pseudomonas-aeruginosa
#14
Benjamin M Hariri, Derek B McMahon, Bei Chen, Nithin D Adappa, James N Palmer, David W Kennedy, Robert J Lee
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...
2017: PloS One
https://www.readbyqxmd.com/read/28930136/methanol-extract-from-anogeissus-leiocarpus-dc-guill-et-perr-combretaceae-stem-bark-quenches-the-quorum-sensing-of-pseudomonas-aeruginosa-pao1
#15
Vincent Ouedraogo, Martin Kiendrebeogo
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...
October 6, 2016: Medicines (Basel, Switzerland)
https://www.readbyqxmd.com/read/28928721/onion-peel-ethylacetate-fraction-and-its-derived-constituent-quercetin-4-o-%C3%AE-d-glucopyranoside-attenuates-quorum-sensing-regulated-virulence-and-biofilm-formation
#16
Hanan M Al-Yousef, Atallah F Ahmed, Nasser A Al-Shabib, Sameen Laeeq, Rais A Khan, Md T Rehman, Ali Alsalme, Mohamed F Al-Ajmi, Mohammad S Khan, Fohad M Husain
The resistance and pathogenesis of bacteria could be related to their ability to sense and respond to population density, termed quorum sensing (QS). Inhibition of the QS system is considered as a novel strategy for the development of antipathogenic agents, especially for combating drug-resistant bacterial infections. In the present study, the anti-QS activity of Onion peel ethylacetate fraction (ONE) was tested against Chromobacterium violaceum CV12472 and Pseudomonas aeruginosa PAO1. ONE inhibit the QS-mediated virulence factors production such as violacein in C...
2017: Frontiers in Microbiology
https://www.readbyqxmd.com/read/28904418/leaf-extracts-of-selected-gardening-trees-can-attenuate-quorum-sensing-and-pathogenicity-of-pseudomonas-aeruginosa-pao1
#17
Kaimin Niu, Min Kuk, Haein Jung, Kokgan Chan, Sooki Kim
An increasing concern on resistance to multiple-antibiotics has led to the discovery of novel agents and the establishment of new precaution strategy. Numerous plant sources have been widely studied to reduce virulence of pathogenic bacteria by interfering cell-to-cell based communication called quorum sensing (QS). Leaf extracts of 17 gardening trees were collected and investigated for their anti-QS effects using a sensor strain Chromobacterium violaceum CV026. Methanolic extracts of K4 (Acer palmatum), K9 (Acer pseudosieboldianum) and K13 (Cercis chinensis) leaves were selected for further experiments based on their antagonism effect on QS without inhibiting C...
September 2017: Indian Journal of Microbiology
https://www.readbyqxmd.com/read/28878346/impact-of-phenolic-compounds-in-the-acyl-homoserine-lactone-mediated-quorum-sensing-regulatory-pathways
#18
Md Akil Hossain, Seung-Jin Lee, Na-Hye Park, Abraham Fikru Mechesso, Biruk Tesfaye Birhanu, JeongWoo Kang, Md Ahsanur Reza, Joo-Won Suh, Seung-Chun Park
Quorum sensing (QS) is a cell density-dependent regulation of virulent bacterial gene expression by autoinducers that potentially pertains in the epidemic of bacterial virulence. This study was initially designed to evaluate the effect of 5 phenolic compounds in the modulation of QS and virulence factors of Chromobacterium violaceum and Pseudomonas aeruginosa, and to determine the mechanisms of their effects. Biosensor strains were used to assess antibacterial and anti-QS effect of these compounds. Only methyl gallate (MG) among these compounds demonstrated profound anti-QS effect in the preliminary study, and thus only MG was utilized further to evaluate the effects on the synthesis and activity of acyl homoserine lactone (AHL) in C...
September 6, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28867635/effect-of-human-placental-extract-in-the-management-of-biofilm-mediated-drug-resistance-a-focus-on-wound-management
#19
Sutapa Goswami, Ratul Sarkar, Pritam Saha, Amit Maity, Tridib Sarkar, Debmalya Das, Piyali Datta Chakraborty, Subhasri Bandyopadhyay, Chandan Kumar Ghosh, Sanmoy Karmakar, Tuhinadri Sen
Management of infectious wounds, particularly chronic wounds and burn injuries, is a matter of global concern. Worldwide estimates reveal that, billions of dollars are being spent annually for the management of such chronic ailments. Evidently, bacterial biofilms pose a greater problem in the effective management of infection in chronic wounds, since most of the currently available antibiotics are unable to act on the microorganisms residing inside the protected environment of the biofilms. Accordingly, in the present study, we have attempted to evaluate the anti-biofilm properties of human placental extract (PLX) and also other virulence factors that are mediated via the quorum sensing (QS) signalling system...
October 2017: Microbial Pathogenesis
https://www.readbyqxmd.com/read/28860065/chitosan-extracted-from-aspergillus-flavus-shows-synergistic-effect-eases-quorum-sensing-mediated-virulence-factors-and-biofilm-against-nosocomial-pathogen-pseudomonas-aeruginosa
#20
Sahira Nsayef Muslim, Israa M S Al Kadmy, Alaa Naseer Mohammed Ali, Batool Kadham Salman, Mohammad Ahmad, Saba Saadoon Khazaal, Nadheema Hammood Hussein, Sraa Nsayef Muslim
The biological methods for extraction of chitosan were used as alternative procedures for chemical methods In biological methods, the chitosan was extracted from A. flavus by using of Lactobacillus paracasei for demineralization and Bacillus subtilis for deproteinization. The yield of extracted chitosan reached to 53.8%, pH was 7.8 and complete solubility in 1% acitic acid. Purified chitosan had the ability to reduce the biofilm forming capacity of P. aeruginosa clearly visible in light microscopic staining and scanning electron microscopy...
August 28, 2017: International Journal of Biological Macromolecules
keyword
keyword
117414
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"