Consulta: subjectFacets:"Quorum sensing"
Registros recuperados: 16
Data/hora: 07/06/2024 08:47:36

Estudio fitoquímico y evaluación de la actividad inhibidora del sistema de censado quórum bacteriano, de las cortezas de Amphipterygium adstringens (Schltdl.) Standl. y Ceiba spp.
Provedor de dados: 32
Autores: Muñoz Cazares, Naybi Rosario.
La comunicación bacteriana o censado de quórum, es un proceso de expresión de genes a nivel poblacional, dependiente de la densidad bacteriana y mediado por moléculas llamadas autoinductoras, que regula entre otros fenotipos, la expresión de los factores de virulencia. La inhibición del sistema de censado de quórum (I-SCQ), se considera un nuevo blanco, con mecanismo de acción distinto al de los antibióticos. El objetivo de este proyecto, consistió en realizar un estudio biodirigido de la actividad I-SCQ de las cortezas de Amphypterygium adstringens, Ceiba pentandra y Ceiba aesculifolia, empleando el modelo de inhibición de violaceína en Chromobacterium violaceum. Los resultados obtenidos, indican la presencia de fracciones activas para las tres cortezas,...
Palavras-chave: Comunicación bacteriana; Censado de quórum bacteriano; Amphipterygium adstringens; Ceiba aesculifolia; Ceiba pentandra; Anti-censado de quórum; Plantas anti-quórum; Bacterial communication; Quorum sensing; Anti-quorum sensing; Anti-quorum plants; Botánica; Maestría.
Ano: 2013
URL: http://hdl.handle.net/10521/2081

Analysis of the molecular basis of Xanthomonas axonopodis pv. citri pathogenesis in Citrus limon
Provedor de dados: 69
Autores: Siciliano,Florencia; Torres,Pablo; Sendín,Lorena; Bermejo,Carolina; Filippone,Paula; Vellice,Gabriel; Ramallo,Jackie; Castagnaro,Atilio; Vojnov,Adrian; Marano,María Rosa.
Xanthomonas axonopodis pathovar citri (Xac) causes bacterial citrus canker, a serious disease of most citrus species. Xanthomonas campestris pv. campestris (Xcc) is the causal agent of black rot disease in cruciferous plants. In Xcc, cell-cell signaling is mediated by diffusible signal factor (DSF). Synthesis of DSF depends on RpfB and RpfF. DSF perception and signal transduction have been suggested to involve a two-component system comprising RpfC and RpfG. It has been proposed that these proteins participate in a signal transduction system linking changes in the environment to the synthesis of DSF and the expression of virulence genes. Although the cluster of the rpf genes in Xac has synteny with the corresponding cluster in Xcc, two genes (rpfH and...
Tipo: Journal article
Palavras-chave: Canker; DSF; Extracellular polysaccharide; Quorum sensing.
Ano: 2006
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582006000300005

Relation between Biofilm and Virulence in Vibrio tapetis: A Transcriptomic Study
Provedor de dados: 5
Autores: Rodrigues, Sophie; Paillard, Christine; Van Dillen, Sabine; Tahrioui, Ali; Berjeaud, Jean-marc; Dufour, Alain; Bazire, Alexis.
Marine pathogenic bacteria are able to form biofilms on many surfaces, such as mollusc shells, and they can wait for the appropriate opportunity to induce their virulence. Vibrio tapetis can develop such biofilms on the inner surface of shells of the Ruditapes philippinarum clam, leading to the formation of a brown conchiolin deposit in the form of a ring, hence the name of the disease: Brown Ring Disease. The virulence of V. tapetis is presumed to be related to its capacity to form biofilms, but the link has never been clearly established at the physiological or genetic level. In the present study, we used RNA-seq analysis to identify biofilm- and virulence-related genes displaying altered expression in biofilms compared to the planktonic condition. A...
Tipo: Text
Palavras-chave: Biofilm; Virulence; Vibrio tapetis; Transcriptome; Quorum sensing; Type VI secretion system; Brown ring disease.
Ano: 2018
URL: https://archimer.ifremer.fr/doc/00470/58140/60611.pdf

Microbiology and immunology of fish larvae
Provedor de dados: 5
Autores: Vadstein, Olav; Bergh, Oivind; Gatesoupe, Joel; Galindo-villegas, Jorge; Mulero, Victoriano; Picchietti, Simona; Scapigliati, Giuseppe; Makridis, Pavlos; Olsen, Yngvar; Dierckens, Kristof; Defoirdt, Tom; Boon, Nico; De Schryver, Peter; Bossier, Peter.
For most marine aquaculture species, one of the main bottlenecks is the stable production of high quality juveniles. The high and unpredictable mortality in the first weeks after hatching of marine fish larvae remains a challenging problem that needs to be solved. The severity of the problem differs between species, but cannot be considered adequately solved for any species. Both scientific evidence and experience in hatcheries for a variety of fish, shrimp and shellfish species are accumulating as support for the hypothesis that detrimental fish-microbe interactions are the cause of these problems. Host-microbe interactions in reared fish are still poorly understood, except for a few pathogens, and empirical data of the quality required to test this...
Tipo: Text
Palavras-chave: Host-microbe interaction; Mast cell; Microbial ecology; Piscidin; Quorum sensing.
Ano: 2013
URL: http://archimer.ifremer.fr/doc/00144/25510/23654.pdf

Quorum sensing inhibitors from Leucetta chagosensis Dendy, 1863
Provedor de dados: 5
Autores: Mai, T.; Tintillier, Florent; Lucasson, Aude; Moriou, C.; Bonno, E.; Petek, S.; Magre, Kevin; Al Mourabit, A.; Saulnier, Denis; Debitus, C.
Sponges are a rich source for investigation of bioactive small molecules. They have been mostly investigated for the search of new pharmacological models or therapeutic agents for the treatment of human diseases. Micro-organisms can also represent a virulent pathogen for marine invertebrates such as sponges, which need to protect themselves against these microbes. Sponges' self defence mechanisms involving dialogue molecules thus represent a pertinent research track for potent anti-infective and anti-biofilm activities such as quorum sensing inhibitors (QSIs). The investigation of the QSI crude extract of Leucetta chagosensis Dendy, 1863 led to the isolation of three new alkaloids, isonaamine D, di-isonaamidine A and leucettamine D, along with the known...
Tipo: Text
Palavras-chave: Biofouling; Leucetta chagosensis; Leucettamine; Naamidine; Naamine; Quorum sensing; Quorum sensing inhibitors; Sponges; Vibrio harveyi.
Ano: 2015
URL: http://archimer.ifremer.fr/doc/00275/38597/37189.pdf

Diversity of quorum sensing autoinducer synthases in the Global Ocean Sampling metagenomic database
Provedor de dados: 5
Autores: Doberva, Margot; Sanchez-ferandin, Sophie; Toulza, Eve; Lebaron, Philippe; Lami, Raphael.
Quorum sensing (QS) is a cell-to-cell signalling pathway that allows bacteria to synchronize their genetic expression. It is mediated by autoinducers (AI), including (1) acyl-homoserine lactones (AHLs or AI-1), produced by Proteobacteria using AinS, LuxI and HdtS synthase families and (2) furanosyl-diester-borate (FDB or AI-2), produced by a large range of phylogenetically diverse bacteria and synthetized by the LuxS family. Few data have been collected about the presence and importance of QS in marine waters using culture independent methods. In this study, we examined the presence and the diversity of AI-1 and AI-2 synthases in the Global Ocean Sampling (GOS), a large metagenomic database, covering 68 stations across 3 oceans. We built 4 reference...
Tipo: Text
Palavras-chave: Quorum sensing; Acyl-homoserine lactone synthases; Global Ocean Sampling; Environmental metagenomes.
Ano: 2015
URL: https://archimer.ifremer.fr/doc/00615/72718/71710.pdf

Sponge-Inspired Dibromohemibastadin Prevents and Disrupts Bacterial Biofilms without Toxicity
Provedor de dados: 5
Autores: Le Norcy, Tiffany; Niemann, Hendrik; Proksch, Peter; Tait, Karen; Linossier, Isabelle; Rehel, Karine; Hellio, Claire; Fay, Fabienne.
Since the banning of several families of compounds in antifouling (AF) coatings, the search for environmentally friendly AF compounds has intensified. Natural sources of AF compounds have been identified in marine organisms and can be used to create analogues in laboratory. In a previous study, we identified that dibromohemibastadin-1 (DBHB) is a promising AF molecule, leading to the inhibition of the activity of phenoloxidase, an enzyme involved in the attachment of mussels to surfaces. This paper describes the activity of the DBHB on biofilm formation and its detachment and on bacterial adhesion and communication: quorum sensing. DBHB has an anti-biofilm activity without affecting adhesion of marine and terrestrial bacteria at a dose of 10 mu M....
Tipo: Text
Palavras-chave: Biofouling; Biofilm; Bastadin derivative; Microfouling; Quorum sensing; Sponge.
Ano: 2017
URL: https://archimer.ifremer.fr/doc/00616/72813/72581.pdf

First molecular evidence of cross-species induction of metalloprotease gene expression in Vibrio strains pathogenic for Pacific oyster Crassostrea gigas involving a quorum sensing system
Provedor de dados: 5
Autores: De Decker, Sophie; Reynaud, Yann; Saulnier, Denis.
The aim of that studywas to explore the hypothesis that a quorumsensingmechanismmodulatesmetalloprotease gene expression of two Vibrio species pathogenic for oyster, at intraspecific (Vibrio splendidus) and interspecific (V. splendidus affecting V. aestuarianus) levels. Metalloprotease activities (Vsm for V. splendidus LGP32 and Vam for V. aestuarianus 02/041) and growth curves obtained by real-time PCR assay revealed cell density-dependent metalloprotease inductions triggered between 12 h and 16 h of culture. A quorum sensing assay was then developed using a conditioned medium prepared from supernatant of a mutant strain of V. splendidus LGP32 unable to produce metalloprotease. Specific real-time qPCR assays targeting metalloprotease genes vsm and vam...
Tipo: Text
Palavras-chave: Quorum sensing; Crassostrea gigas; Vibrio; Metalloprotease; Gene expression.
Ano: 2013
URL: http://archimer.ifremer.fr/doc/00124/23539/21381.pdf

A structural perspective on the mechanisms of quorum sensing activation in bacteria
Provedor de dados: 42
Autores: LIXA,CAROLINA; MUJO,AMANDA; ANOBOM,CRISTIANE D.; PINHEIRO,ANDERSON S.
Bacteria are able to synchronize the population behavior in order to regulate gene expression through a cell-to-cell communication mechanism called quorum sensing. This phenomenon involves the production, detection and the response to extracellular signaling molecules named autoinducers, which directly or indirectly regulate gene expression in a cell density-dependent manner. Quorum sensing may control a wide range of biological processes in bacteria, such as bioluminescence, virulence factor production, biofilm formation and antibiotic resistance. The autoinducers are recognized by specific receptors that can either be membrane-bound histidine kinase receptors, which work by activating cognate cytoplasmic response regulators, or cytoplasmic receptors...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Autoinducer; Bacteria; Quorum sensing; Receptor; Structure.
Ano: 2015
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652015000502189

Biofilm formation and acyl homoserine lactone production in Hafnia alvei isolated from raw milk
Provedor de dados: 48
Autores: SOUZA VIANA,ELISETH; MARTINO CAMPOS,MARIA EMILENE; REIS PONCE,ADRIANA; CUQUETTO MANTOVANI,HILÁRIO; DANTAS VANETTI,MARIA CRISTINA.
The objective of this study was to detect the presence of acyl homoserine lactones (AHLs), signal molecules of the quorum sensing system in biofilm formed by Hafnia alvei strains. It also evaluated the effect of synthetic quorum sensing inhibitors in biofilm formation. AHLs were assayed using well diffusion techniques, thin layer chromatography (TLC) and detection directly in biofilm with biomonitors. The extracts obtained from planktonic and sessile cell of H. alvei induced at least two of three monitor strains evaluated. The presence of AHLs with up to six carbon atoms was confirmed by TLC. Biofilm formation by H. alvei was inhibited by furanone, as demonstrated by 96-well assay of crystal violet in microtitre plates and by scanning electron microscopy....
Tipo: Journal article
Palavras-chave: Acyl homoserines lactones; Biofilm; Furanones; Quorum sensing.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602009000400004

Lack of AHL-based quorum sensing in Pseudomonas fluorescens isolated from milk
Provedor de dados: 58
Autores: Martins,Maurilio L.; Uelinton,M. Pinto; Riedel,Kathrin; Vanetti,Maria C.D.; Mantovani,Hilário C.; Araújo,Elza F. de.
Numerous bacteria coordinate gene expression in response to small signalling molecules in many cases known as acylhomoserine lactones (AHLs), which accumulate as a function of cell density in a process known as quorum sensing. This work aimed to determine if phenotypes that are important to define microbial activity in foods such as biofilm formation, swarming motility and proteolytic activity of two Pseudomonas fluorescens strains, isolated from refrigerated raw milk, are influenced by AHL molecules. The tested P. fluorescens strains did not produce AHL molecules in none of the evaluated media. We found that biofilm formation was dependent on the culture media, but it was not influenced by AHLs. Our results indicate that biofilm formation, swarming...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Milk; Pseudomonas fluorescens; Biofilm formation; Quorum sensing; Quorum quenching.
Ano: 2014
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822014000300037

Iron-depletion prevents biofilm formation in Pseudomonas aeruginosa through twitching motility and quorum sensing
Provedor de dados: 58
Autores: Cai,Yun; Wang,Rui; An,Mao-Mao; Bei-Bei,Liang.
Influence of iron-depletion on twitching motility and quorum sensing (QS) system in P. aeruginosa was evaluated. The results demonstrated iron-depletion can retard biofilm formation and increase the twitching motility and expression of QS-related genes, suggesting a potential interaction between twitching motility and QS system in P. aeruginosa biofilm formation.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Iron; Biofilm; Twitching motility; Quorum sensing.
Ano: 2010
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822010000100008

Roles of quorum sensing molecules from Rhizobium etli RT1 in bacterial motility and biofilm formation
Provedor de dados: 58
Autores: Dixit,Swarnita; Dubey,Ramesh Chand; Maheshwari,Dinesh Kumar; Seth,Prahlad Kishore; Bajpai,Vivek K.
ABSTRACT Strain RT1 was isolated from root nodules of Lens culinaris (a lentil) and characterized as Rhizobium etli (a Gram-negative soil-borne bacterium) by 16S rDNA sequencing and phylogenetic analysis. The signaling molecules produced by R. etli (RT1) were detected and identified by high-performance liquid chromatography coupled with mass spectrometry. The most abundant and biologically active N-acyl homoserine lactone molecules (3-oxo-C8-HSL and 3-OH-C14-HSL) were detected in the ethyl acetate extract of RT1. The biological role of 3-oxo-C8-HSL was evaluated in RT1. Bacterial motility and biofilm formation were affected or modified on increasing concentrations of 3-oxo-C8-HSL. Results confirmed the existence of cell communication in RT1 mediated by...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Rhizobium etli; Quorum sensing; Motility; Biofilm; Lens culinaris.
Ano: 2017
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822017000400815

The proteolytic activity of Pseudomonas fluorescens 07A isolated from milk is not regulated by quorum sensing signals
Provedor de dados: 58
Autores: Pinto,Uelinton M.; Costa,Esther D.; Mantovani,Hilario C.; Vanetti,M.C.D.
The proteolytic activity of Pseudomonas fluorescens 07A was investigated, and was optimal on tryptone-calcium medium. N-acyl-homoserine lactones (AHLs) were not detected on supernatants of late-exponential and stationary-phase culture broths. Synthetic AHLs or bacterial cell extracts added to the medium did not influence growth or proteolytic activity suggesting that quorum sensing might not regulate protease production in this strain.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Pseudomonas fluorescens; Proteolytic activity; Quorum sensing.
Ano: 2010
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822010000100015

2(5H)-Furanone: a prospective strategy for biofouling-control in membrane biofilm bacteria by quorum sensing inhibition
Provedor de dados: 58
Autores: Ponnusamy,Kannan; Paul,Diby; Kim,Young Sam; Kweon,Ji Hyang.
Biofouling of membranes demands costly periodic cleaning and membrane replacement. A sustainable and environmentally friendly solution for maintenance is not available and would be of great interest for many purposes including economical. As complex biofilm formation by environmental strains is the major cause of biofouling and biofilm formation in most cases are controlled by N-Acylhomoserine lactone (AHL)mediated Quorum Sensing (QS). An effort was made to understand the appropriateness of 2(5H)-furanone, to use against biofouling of membranes. QS inhibition activity by 2(5H)-furanone was studied using bioindicator strains and known AHLs of different acyl chain lengths. The biofilm inhibition was studied by growth analysis on polystyrene plate of...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Furanone; Biofilm; Water treatment; Quorum sensing; N-Acyl homoserine lactone.
Ano: 2010
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822010000100032

Inducers and autoinducers on Salmonella enterica serovar Typhimurium motility, growth and gene expression
Provedor de dados: 65
Autores: Conceição,Rita de Cássia dos Santos da; Sturbelle,Régis Tuchtenhagen; Timm,Cláudio Dias; Leite,Fábio Pereira Leivas.
Genus Salmonella bacteria are among the major pathogenic microorganisms in food. This bacterium pathogenicity is related to a number of virulence factors, among which its flagella. Flagellum expression is one of the virulence factors modulated by Quorum Sensing. Epinephrine produced by mammals uses the same signaling pathway of the 3 bacteria autoinducer. This study evaluated the effect of molecules inducer (epinephrine) and autoinducers (autoinducer 2 and autoinducer 3) and their association with the motility, growth and expression genes flhC, fliA, fliY, motA, motB e fliC of Salmonella Typhimurium (ST). Initially, ST was inoculated in BHI. Then, motility assays, growth curves and gene expression were performed by testing different concentrations of...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Quorum sensing; Salmonella; Epinephrine; Autoinducer; Motility.
Ano: 2015
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782015001202201