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Showing 1 to 17 of 17 for “"AHLs"”.
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Microbial interactions associated with biofilms attached to Trichodesmium spp. and detrital particles in the ocean
… sensing (QS) via acylated homoserine lactones (AHLs) was discovered in the ocean, yet little is known about its role in the ocean beyond its involvement in certain symbiotic interactions. The objectives of this thesis were to constrain the chemical stability of AHLs in seawater, explore the …
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Microbial interactions associated with biofilms attached to Trichodesmium spp. and detrital particles in the ocean
… sensing (QS) via acylated homoserine lactones (AHLs) was discovered in the ocean, yet little is known about its role in the ocean beyond its involvement in certain symbiotic interactions. The objectives of this thesis were to constrain the chemical stability of AHLs in seawater, explore the …
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Structural and Mechanistic Roles of Novel Chemical Ligands on Quorum Sensing Transcription Regulator SdiA in Enterohemorrhagic Escherichia coli
… signaling molecules, acyl-homoserine lactones (AHLs) [1]. However, some bacteria such as Escherichia coli (E. coli) do not produce AHLs and, therefore, their quorum sensing LuxR-type proteins are thought to be regulated by AHLs from other bacteria [2-4]. These sub-family of LuxR proteins known …
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Chemical Processes That Govern the Natural Attenuation of Microbial Signals: Environments That Simulate Photosynthetic Biofilms
… communication, the acylhomoserine lactones (AHLs) and a family of 4,5-dihydroxy-2,3-pentanedione (DPD) derivatives functionally classified as autoinducer-2 (AI2). Oxidative attenuation of the acylhomoserine lactones (AHLs) by hydroxyl radicals results in the formation of keto- and hydroxo …
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Molecular and transcriptomic studies of quorum sensing in Chromobacterium subtsugae
… to bet hedging.CviR can respond to a variety of AHLs in addition to C6-HSL. Previously, it was shown that the promiscuous activation of CviR by B. thailandensis AHLs provides a competitive advantage to C. subtsugae. Here, we show that B. thailandensis AHLs activate transcription of dozens of …
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The Influence of Changes In theMolecular Structure of N-Acylhomoserine Lactones On the Complexation and Dna-Binding of Luxr Protein
… cognate autoinducer N-acylhomoserine lactones (AHLs), thereby inducing a conformational change and subsequently binding to lux box-like target genes to regulate transcription. The study of the first identified quorum-sensing system, the Vibrio fischeri LuxI/LuxR paradigm, was limited to …
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Raman Studies of Acyl-Homoserine Lactones
… for the detection of N-acyl homoserine lactones (AHLs), which are quorum sensing molecules used in bacterial communication. The advantage of using Raman spectroscopy over other techniques is the possibility of in-situ detection of these molecules within their natural environment. The biggest issue …
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Indução do mecanismo de quorum sensing por autoindutor-1 em Salmonella enterica e prospecção de inibidores
… a proteína LuxR, que permite detectar as AHLs produzidas por outras bactérias. A influência da AHL sobre a expressão de genes específicos de Salmonella, como os genes do operon rck e outros genes de virulência é reconhecida. Entretanto, poucos são os estudos que avaliaram a resposta global …
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Evidence of Water to Human Transmission of Aeromonas Hydrophila: Critical Role of Quorum Sensing in Bacterial Virulence & Host Response
… the role of N-acyl homoserine lactones (AHLs; autoinducer-1 [AI-1])-mediated quorum sensing (QS) in the virulence of a diarrheal isolate SSU of A. hydrophila by generating a ΔahyRI mutant. Our data suggested that AI-1-mediated QS modulated the in vitro virulence of A. hydrophila by …
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Engineering of the quorum quenching lactonase GcL for altered substrate specificity by rational design
… systems utilizing Acyl Homoserine Lactones (AHLs) are prominent in many microbial organisms and communities of high impact to human interests. These include certain agricultural and human pathogens, biofilm production, and aquatic biofouling. The structure of AHLs is variable and these …
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The Functional Characterization of QSEC a Bacterial Adrenergic Receptor and the LuxR Homologue SDIA in EHEC
… homologue, indicating that it can respond to AHLs through SdiA, but cannot produce them. EHEC uses SdiA to sense its environment through other AHL-producing bacteria. Microarray analysis and qPCR confirmed that, in response to AHL, SdiA represses the transcription of the LEE genes, which …
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Insights into the Substrate Binding Specificity of Quorum-Quenching Acylase PVDQ
… sensing signaling N-acyl homoserine lactones (AHLs) thereby degrading the signaling molecules, inhibiting the biofilm formation and reducing virulence gene expression. Previous studies demonstrated that PvdQ has different preferences for AHLs with different acyl chain lengths and substituents. …
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Signalling Molecule Production by Escherichia coli and Campylobacter jejuni
… molecules, including acyl-homoserine lactones (AHLs), have now been identified in numerous bacterial species. AHL production by clinical and laboratory isolates of Escherichia coli and Campylobacter jejuni has been investigated in this study. Laboratory, blood and urine E.coli isolates were …
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Controlling Biofouling by Surface Engineering and Molecular Inhibition
… molecules called acylated homoserine lactones (AHLs). The synthesized brominated furanone derivatives and SHLs were found to be non-toxic to <em>E. coli</em> and were able to inhibit the biofilm formation by the bacterium.
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Comparative analysis of desiccation responses in three Xerophyta species at two stages of seedling development
… Heat Shock Factors (HSFs), A-T hook factors (AHLs), and C2H2 Zinc Finger Proteins (ZATs). The gene ontology enrichment showed that the HSF, AHL, and ZAT motif containing OGs that were up-regulated are involved in water deprivation, abscisic acid response, and oxidative stress response …
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Preventive Measures in Aquaculture: Isolation, Application and Effects of Probiotics on Atlantic cod (Gadus morhua L.) Rearing at Early Stages
… traits, including haemolysin, siderophores and AHLs, were studied among bacterial isolates and related to larval survival. The results clearly demonstrate the influence of exogeneous feeding and treatments on larval gastrointestinal microbiota, and the role of bacteria in larval survival. During …
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Novel small molecules for modulation of bacterial signaling pathways
… such as N-acylated L-homoserine lactones (AHLs), indoles, N-acetyl glucosamine and other heterocyclic systems derived from halogenated furanones (Fimbrolides). Indole and glucosamine-based amides and oxo-amides were synthesized as non-native AHL mimics by applying EDC, DCC or EDC/HOBt …