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Quorum sensing, Quorum quenching, Pseudomonas aeruginosa

Subramaniyan S, Divyasree S, Sandhia G S
BACKGROUND: Quorum sensing or the bacterial information flow in an orchestrated manner is an essential feature of many pathogenic bacteria. Quorum quenching molecules (QQ) can inhibit the growth of such bacteria. OBJECTIVE: The purpose of this study is to evaluate the potential of plant extracts as quorum quenchers and monitor the recent patents. METHODS: Many available reports and patents are on synthetic ligand molecules or even compounds isolated from cyanobacteria (Honaucin A) and other microorganisms inhibiting quorum sensing molecules...
September 8, 2016: Recent Patents on Biotechnology
Xin Cathy Li, Christopher Wang, Ashok Mulchandani, Xin Ge
Many pathogenic bacteria utilize quorum sensing (QS) systems to regulate the expression of their virulence genes and promote the formation of biofilm, which renders pathogens with extreme resistance to conventional antibiotic treatments. As a novel approach for attenuating antibiotic resistance and in turn fighting chronic infections, enzymatic inactivation of QS signaling molecules, such as N-acyl homoserine lactones (AHLs), holds great promises. Instead of using bacterial lactonases that can evoke immune response when administered, we focus on the human paraoxonase 2 (huPON2)...
September 30, 2016: ACS Chemical Biology
Ketema Bacha, Yinebeb Tariku, Fisseha Gebreyesus, Shibru Zerihun, Ali Mohammed, Nancy Weiland-Bräuer, Ruth A Schmitz, Mulugeta Mulat
BACKGROUND: Traditional medicinal plants have been used as an alternative medicine in many parts of the world, including Ethiopia. There are many documented scientific reports on antimicrobial activities of the same. To our knowledge, however, there is no report on the anti-Quorum Sensing (Quorum Quenching, QQ) potential of traditional Ethiopian medicinal plants. As many of the opportunistic pathogenic bacteria depend on Quorum Sensing (QS) systems to coordinate their virulence expression, interference with QS could be a novel approach to control bacterial infections...
2016: BMC Microbiology
Clement E Furlong, Judit Marsillach, Gail P Jarvik, Lucio G Costa
Paraoxonase-1 (PON1), an esterase/lactonase primarily associated with plasma high-density lipoprotein (HDL), was the first member of this family of enzymes to be characterized. Its name was derived from its ability to hydrolyze paraoxon, the toxic metabolite of the insecticide parathion. Related enzymes PON2 and PON3 were named from their evolutionary relationship with PON1. Mice with each PON gene knocked out were generated at UCLA and have been key for elucidating their roles in organophosphorus (OP) metabolism, cardiovascular disease, innate immunity, obesity, and cancer...
May 26, 2016: Chemico-biological Interactions
Maria José Valera, Albert Mas, Wolfgang R Streit, Estibaliz Mateo
BACKGROUND: We report on the functional screening and identification of an active quorum quenching (QQ) gene in the Komagataeibacter europaeus strain CECT 8546, which is a member of the acetic acid bacteria (AAB). RESULTS: Using a previously published screening protocol (Schipper et al., in Appl Environ Microbiol 75:224-233, 2009. doi: 10.1128/AEM.01389-08 ) for QQ genes, we identified a single gene, designated gqqA, that interfered strongly with bacterial quorum sensing (QS) in various reporter strains...
2016: Microbial Cell Factories
Kok-Gan Chan, Yi-Chia Liu, Chien-Yi Chang
Bacteria sense their own population size, tune the expression of responding genes, and behave accordingly to environmental stimuli by secreting signaling molecules. This phenomenon is termed as quorum sensing (QS). By exogenously manipulating the signal transduction bacterial population behaviors could be controlled, which may be done through quorum quenching (QQ). QS related regulatory networks have been proven their involvement in regulating many virulence determinants in pathogenic bacteria in the course of infections...
2015: Frontiers in Microbiology
Christine Müller, Franziska S Birmes, Christian Rückert, Jörn Kalinowski, Susanne Fetzner
Rhodococcus erythropolis BG43 is able to degrade the Pseudomonas aeruginosa quorum sensing signal molecules PQS (Pseudomonas quinolone signal) [2-heptyl-3-hydroxy-4(1H)-quinolone] and HHQ [2-heptyl-4(1H)-quinolone] to anthranilic acid. Based on the hypothesis that degradation of HHQ might involve hydroxylation to PQS followed by dioxygenolytic cleavage of the heterocyclic ring and hydrolysis of the resulting N-octanoylanthranilate, the genome was searched for corresponding candidate genes. Two gene clusters, aqdA1B1C1 and aqdA2B2C2, each predicted to code for a hydrolase, a flavin monooxygenase, and a dioxygenase related to 1H-3-hydroxy-4-oxoquinaldine 2,4-dioxygenase, were identified on circular plasmid pRLCBG43 of strain BG43...
November 2015: Applied and Environmental Microbiology
Christian Rückert, Franziska S Birmes, Christine Müller, Heiko Niewerth, Anika Winkler, Susanne Fetzner, Jörn Kalinowski
Rhodococcus erythropolis BG43 was isolated from soil and characterized as a degrader of the quorum sensing signal molecules 2-heptyl-3-hydroxy-4(1H)-quinolone (the Pseudomonas quinolone signal, PQS) and 2-heptyl-4(1H)-quinolone, produced by Pseudomonas aeruginosa. The complete genome of R. erythropolis BG43 consists of a circular chromosome and three plasmids, one of them circular and two linear ones. In total, 6158 protein-coding regions were identified. With this genome sequence, the genetic basis of its quorum-quenching ability and possible biotechnological applications can be explored further...
October 10, 2015: Journal of Biotechnology
B García-Lara, M Á Saucedo-Mora, J A Roldán-Sánchez, B Pérez-Eretza, M Ramasamy, J Lee, R Coria-Jimenez, M Tapia, V Varela-Guerrero, R García-Contreras
UNLABELLED: Quorum quenching decreases Pseudomonas aeruginosa virulence factors and biofilm formation, alleviating infections in animal models. Nevertheless, it is usually performed in laboratory strains such as PAO1 and PA14, and studies involving clinical or environmental isolates are scarce. In this work, the effects of ZnO nanoparticles, a potent quorum and virulence quencher for the PAO1 strain, were tested in six clinical strains from cystic fibrosis patients, a furanone C-30 resistant clinical strain from urine, two PA14 gallium resistant mutants, a PA14 C-30 resistant mutant and four environmental isolates...
September 2015: Letters in Applied Microbiology
Rodolfo García-Contreras, Berenice Peréz-Eretza, Ricardo Jasso-Chávez, Elizabeth Lira-Silva, Jesús Alberto Roldán-Sánchez, Abigail González-Valdez, Gloria Soberón-Chávez, Rafael Coria-Jiménez, Mariano Martínez-Vázquez, Luis David Alcaraz, Toshinari Maeda, Thomas K Wood
Pseudomonas aeruginosa colonizes the lungs of cystic fibrosis patients causing severe damage. This bacterium is intrinsically resistant to antibiotics and shows resistance against new antimicrobials and its virulence is controlled by the quorum-sensing response. Thus, attenuating its virulence by quorum quenching instead of inhibiting its growth has been proposed to minimize resistance; however, resistance against the canonical quorum quencher furanone C-30 can be achieved by mutations leading to increased efflux...
August 2015: Pathogens and Disease
Eliza Ye-Chen Soh, Siri R Chhabra, Nigel Halliday, Stephan Heeb, Christine Müller, Franziska S Birmes, Susanne Fetzner, Miguel Cámara, Kok-Gan Chan, Paul Williams
In Pseudomonas aeruginosa, quorum sensing (QS) regulates the production of secondary metabolites, many of which are antimicrobials that impact on polymicrobial community composition. Consequently, quenching QS modulates the environmental impact of P. aeruginosa. To identify bacteria capable of inactivating the QS signal molecule 2-heptyl-3-hydroxy-4(1H)-quinolone (PQS), a minimal medium containing PQS as the sole carbon source was used to enrich a Malaysian rainforest soil sample. This yielded an Achromobacter xylosoxidans strain (Q19) that inactivated PQS, yielding a new fluorescent compound (I-PQS) confirmed as PQS-derived using deuterated PQS...
November 2015: Environmental Microbiology
Gurpreet Singh, Ekant Tamboli, Aurovind Acharya, Chellan Kumarasamy, Kanchana Mala, Pachaiappan Raman
Cell-to-cell communication or quorum sensing (QS) is a generic event in bacteria that is used to coordinate gene expression among local populations. The phenomenon of QS depends on the fact that presence of sufficient bacteria ascertains a threshold level of autoinducer concentration that allows bacteria to sense a critical cell mass and to activate or repress target genes. Thus, QS has been an attractive target for the development of anti-infective strategies that are not based on the use of antibiotics. Several anti-QS approaches have been demonstrated including natural products from plant-based secondary metabolites...
June 2015: Medical Hypotheses
Kristina Ivanova, Margarida M Fernandes, Ernest Mendoza, Tzanko Tzanov
Bacteria use a signaling mechanism called quorum sensing (QS) to form complex communities of surface-attached cells known as biofilms. This protective mode of growth allows them to resist antibiotic treatment and originates the majority of hospital-acquired infections. Emerging alternatives to control biofilm-associated infections and multidrug resistance development interfere with bacterial QS pathways, exerting less selective pressure on bacterial population. In this study, biologically stable coatings comprising the QS disrupting enzyme acylase were built on silicone urinary catheters using a layer-by-layer technique...
May 2015: Applied Microbiology and Biotechnology
G A Achari, R Ramesh
UNLABELLED: Bacterial wilt pathogen Ralstonia solanacearum causes severe crop loss of eggplant, which is of economic importance in India. 3-hydroxy palmitic acid methyl ester (3OH-PAME) is the main quorum sensing molecule governing the expression of virulence factors in R. solanacearum. Ability of 164 bacterial isolates from the xylem of eggplant (Solanum melongena L.), chilli pepper (Capsicum annuum L.) and wild eggplant (Solanum torvum Sw.) to degrade 3OH-PAME was tested by disc diffusion assay...
May 2015: Letters in Applied Microbiology
Kaihao Tang, Ying Su, Gilles Brackman, Fangyuan Cui, Yunhui Zhang, Xiaochong Shi, Tom Coenye, Xiao-Hua Zhang
Gram-negative bacteria use N-acyl homoserine lactones (AHLs) as quorum sensing (QS) signaling molecules for interspecies communication, and AHL-dependent QS is related with virulence factor production in many bacterial pathogens. Quorum quenching, the enzymatic degradation of the signaling molecule, would attenuate virulence rather than kill the pathogens, and thereby reduce the potential for evolution of drug resistance. In a previous study, we showed that Muricauda olearia Th120, belonging to the class Flavobacteriia, has strong AHL degradative activity...
January 2015: Applied and Environmental Microbiology
Sami Hraiech, Julien Hiblot, John Lafleur, Hubert Lepidi, Laurent Papazian, Jean-Marc Rolain, Didier Raoult, Mikael Elias, Mark W Silby, Janek Bzdrenga, Fabienne Bregeon, Eric Chabriere
RATIONALE: The effectiveness of antibiotic molecules in treating Pseudomonas aeruginosa pneumonia is reduced as a result of the dissemination of bacterial resistance. The existence of bacterial communication systems, such as quorum sensing, has provided new opportunities of treatment. Lactonases efficiently quench acyl-homoserine lactone-based bacterial quorum sensing, implicating these enzymes as potential new anti-Pseudomonas drugs that might be evaluated in pneumonia. OBJECTIVES: The aim of the present study was to evaluate the ability of a lactonase called SsoPox-I to reduce the mortality of a rat P...
2014: PloS One
Kenneth D Clevenger, Rui Wu, Dali Liu, Walter Fast
The enzyme PvdQ (E.C. from Pseudomonas aeruginosa is an N-terminal nucleophile hydrolase that catalyzes the removal of an N-myristyl substituent from a biosynthetic precursor of the iron-chelating siderophore pyoverdine. Inhibitors of pyoverdine biosynthesis are potential antibiotics since iron is essential for growth and scarce in most infections. PvdQ also catalyzes hydrolytic amide bond cleavage of selected N-acyl-l-homoserine lactone quorum-sensing signals used by some Gram-negative pathogens to coordinate the transcription of virulence factors...
October 28, 2014: Biochemistry
Nalini Easwaran, Sivashanmugam Karthikeyan, Balasundaram Sridharan, Kodiveri Muthukaliannan Gothandam
Bacterial biofilms communicate by a process called Quorum Sensing. Gram negative bacterial pathogens specifically talk through the production, detection, and response to the signal or autoinducer called Acyl Homoserine Lactones. Bacterial lactonases are important AHL hydrolysing or quorum quenching enzymes. The present study deals with ten endospore forming gram positive isolates of the saltern soil. Preliminary screening for Quorum Quenching activity with the QS Inhibition indicator strain Chromobacterium violaceum ATCC 12472, showed positive activity in four isolates namely TS2, TS16, TSAWB, and TS53B...
May 2015: Journal of Basic Microbiology
Ruoting Pei, Gisella R Lamas-Samanamud
Bacterial growth in biofilms is the major cause of recalcitrant biofouling in industrial processes and of persistent infections in clinical settings. The use of bacteriophage treatment to lyse bacteria in biofilms has attracted growing interest. In particular, many natural or engineered phages produce depolymerases to degrade polysaccharides in the biofilm matrix and allow access to host bacteria. However, the phage-produced depolymerases are highly specific for only the host-derived polysaccharides and may have limited effects on natural multispecies biofilms...
September 2014: Applied and Environmental Microbiology
Kok-Gan Chan, Cheng Siang Wong, Wai-Fong Yin, Xin Yue Chan
Pseudomonas aeruginosa has a broad range of habitation, from aquatic environments to human lungs. The coexistence of quorum-sensing and quorum-quenching activities occurs in P. aeruginosa strain MW3a. In this work, we present the draft genome sequence of P. aeruginosa MW3a, an interesting bacterium isolated from a marine environment.
2014: Genome Announcements
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