A multivalent probe for AI-2 quorum-sensing receptors.
Ontology highlight
ABSTRACT:
SUBMITTER: Garner AL
PROVIDER: S-EPMC3203215 | biostudies-literature | 2011 Oct
REPOSITORIES: biostudies-literature
Similar Datasets
Project description:This SuperSeries is composed of the SubSeries listed below.
2013-09-05 | GSE30342 | GEO
Project description:This SuperSeries is composed of the SubSeries listed below. Refer to individual Series
2013-09-05 | E-GEOD-30342 | biostudies-arrayexpress
Project description:BackgroundGreat excitement accompanied discoveries over the last decade in several Gram-negative and Gram-positive bacteria of the LuxS protein, which catalyzes production of the AI-2 autoinducer molecule for a second quorum sensing system (QS-2). Since the luxS gene was found to be widespread among the most diverse bacterial taxa, it was hypothesized that AI-2 may constitute the basis of a universal microbial language, a kind of bacterial Esperanto. Many of the studies published in this field have drawn a direct correlation between the occurrence of the luxS gene in a given organism and the presence and functionality of a QS-2 therein. However, rarely hathe existence of potential AI-2 receptors been examined. This is important, since it is now well recognized that LuxS also holds a central role as a metabolic enzyme in the activated methyl cycle which is responsible for the generation of S-adenosyl-L-methionine, the major methyl donor in the cell.ResultsIn order to assess whether the role of LuxS in these bacteria is indeed related to AI-2 mediated quorum sensing we analyzed genomic databases searching for established AI-2 receptors (i.e., LuxPQ-receptor of Vibrio harveyi and Lsr ABC-transporter of Salmonella typhimurium) and other presumed QS-related proteins and compared the outcome with published results about the role of QS-2 in these organisms. An unequivocal AI-2 related behavior was restricted primarily to organisms bearing known AI-2 receptor genes, while phenotypes of luxS mutant bacteria lacking these genes could often be explained simply by assuming deficiencies in sulfur metabolism.ConclusionGenomic analysis shows that while LuxPQ is restricted to Vibrionales, the Lsr-receptor complex is mainly present in pathogenic bacteria associated with endotherms. This suggests that QS-2 may play an important role in interactions with animal hosts. In most other species, however, the role of LuxS appears to be limited to metabolism, although in a few cases the presence of yet unknown receptors or the adaptation of pre-existent effectors to QS-2 must be postulated.
| S-EPMC2561040 | biostudies-literature
Project description:The LuxS enzyme, an S-ribosyl-homocysteine lyase, catalyzes the production of the signal precursor for autoinducer-2 mediated quorum sensing (QS-2) in Vibrio. Its widespread occurrence among bacteria is often considered the evidence for a universal language for interspecies communication. Presence of the luxS gene and production of the autoinducer-2 (AI-2) signal have repeatedly been the only evidences presented to assign a functional QS-2 to the most diverse species. In fact, LuxS has a primary metabolic role as part of the activated methyl cycle. In this review we have analyzed the distribution of QS-2 related genes in Enterobacteriaceae by moving the focus of the investigation from AI-2 production to the detection of potential AI-2 receptors. The latter are common in pathogens or endosymbionts of animals, but were also found in a limited number of Enterobacteriaceae of the genera Enterobacter, Klebsiella, and Pantoea that live in close association with plants or fungi. Although a precise function of QS-2 in these species has not been identified, they all show an endophytic or endosymbiontic lifestyle that suggests a role of type-2 quorum sensing in the adaptation to closed ecosystems.
| S-EPMC3386761 | biostudies-literature
Project description:Recent studies have revealed that LuxS/AI-2 quorum sensing (QS) is the most universal cell-to-cell communication in rumen bacteria; however, it remains unknown how they respond to nutritional stress from a diet shift. This study aimed to explore whether a diet shift could trigger rumen bacterial LuxS/AI-2 QS and its influences on rumen fermentation characteristics and bacterial community diversity and composition. A total of fifteen Hu sheep were selected to undergo a pre-shift diet (Pre, concentrate to forage ratio 75:25) for one month and then abruptly switch to a post-shift diet (Post, concentrate to forage ratio 49:51). Results showed that the serum cortisol and immunoglobulin G concentrations were higher in Post than in Pre (p < 0.05). The microbial density, AI-2 concentration, biofilm formation, and the gene expression of ftsH were higher in Post when compared with Pre (p < 0.05), whilst the gene expression of luxS tended to be lower in Post (p = 0.054). The molar concentration of valerate and fermentation efficiency decreased after the diet shift, while the acetate to propionate ratio and the molar proportion of butyrate were higher in Post compared to Pre (p < 0.05). Moreover, the diet shift increased the richness of ruminal bacteria and the relative abundances of Roseburia, Prevotellaceae UCG-001, and Lachnospira, and decreased the relative abundances of Prevotella, Megasphaera, and Dialister (p < 0.05). A difference in trends was also observed in an analysis of similarity (R = 0.1208 and p = 0.064). This study suggests that a diet shift could trigger rumen bacterial LuxS/AI-2 QS by altering microbial density, AI-2 concentration, biofilm formation, and related gene expression, as well as affect the rumen fermentation pattern and bacterial community diversity and composition. This study may provide insight into a potential strategy for relieving nutritional stress via regulating bacterial communication.
| S-EPMC9405308 | biostudies-literature
Project description:The AI-2 quorum-sensing system has been linked to diverse phenotypes and regulatory changes in pathogenic bacteria. In strain CO92, the AI-2 signal is produced in a luxS-dependent manner, reaching maximal levels of 2.5 μM in late logarithmic growth, and both wild type and pigmentation mutant strains made equivalent levels of AI-2. Y. pestis CO92 possesses a chromosomal lsr locus encoding factors involved in the binding and import of AI-2, and confirming this assignment, an lsr deletion increased extracellular pools of AI-2. To assess the functional role of AI-2 sensing in Y. pestis, microarray study was conducted comparing the ∆Pgm strain R88 to a ∆Pgm ∆luxS mutant at 30°C to mimic the flea gut.
2016-01-01 | GSE30108 | GEO
Project description:Autoinducer-2 (AI-2)-mediated quorum sensing (QS) is utilised for both intra- and inter-species communication by a wide variety of bacteria. An understanding of the mechanism of this communication has the potential to elucidate new targets for antibacterial therapeutics. Herein, we report the synthesis of DPD analogues with modified dynamic equilibria and the evaluation of their behaviour in Gram-negative bacteria. None of the compounds showed modulation of QS in S. Typhimurium, and although no antagonism of V. harveyi was observed, chloro-analogue C5-Cl-DPD showed modest agonism in this marine bacterium. This raises the possibility that access to a cyclic form of DPD may not be required for AI-2-mediated QS in V. harveyi.
| S-EPMC4915392 | biostudies-literature
Project description:The AI-2 quorum-sensing system has been linked to diverse phenotypes and regulatory changes in pathogenic bacteria. In strain CO92, the AI-2 signal is produced in a luxS-dependent manner, reaching maximal levels of 2.5 μM in late logarithmic growth, and both wild type and pigmentation mutant strains made equivalent levels of AI-2. Y. pestis CO92 possesses a chromosomal lsr locus encoding factors involved in the binding and import of AI-2, and confirming this assignment, an lsr deletion increased extracellular pools of AI-2. To assess the functional role of AI-2 sensing in Y. pestis, microarray study was conducted comparing the âPgm strain R88 to a âPgm âluxS mutant at 30°C to mimic the flea gut. Six independent RNA samples from Y. pestis CO92 ÎPgm cultures were paired with six independent RNA samples from ÎPgm ÎluxS cultures for hybridization to six two-color microarrays. A dye-swap design was used to remove the Cy5 and Cy3 dye bias.
2016-07-03 | E-GEOD-30108 | biostudies-arrayexpress
Project description:LuxS/AI-2 is an important quorum sensing system which affects the growth, biofilm formation, virulence, and metabolism of bacteria. LuxS is encoded by the luxS gene, but how this gene is associated with a diverse array of physiological activities in Edwardsiella piscicida (E. piscicida) is not known. Here, we constructed an luxS gene mutant strain, the ?luxS strain, to identify how LuxS/AI-2 affects pathogenicity. The results showed that LuxS was not found in the luxS gene mutant strain, and this gene deletion decreased E. piscicida growth compared to that of the wild-type strain. Meanwhile, the wild-type strain significantly increased penetration and motility in mucin compared to levels with the ?luxS strain. The 50% lethal dose (LD50) of the E. piscicida ?luxS strain for zebrafish was significantly higher than that of the wild-type strain, which suggested that the luxS gene deletion could attenuate the strain's virulence. The AI-2 activities of EIB202 were 56-fold higher than those in the ?luxS strain, suggesting that the luxS gene promotes AI-2 production. Transcriptome results demonstrated that between cells infected with the ?luxS strain and those infected with the wild-type strain 46 genes were significantly differentially regulated, which included 34 upregulated genes and 12 downregulated genes. Among these genes, the largest number were closely related to cell immunity and signaling systems. In addition, the biofilm formation ability of EIB202 was significantly higher than that of the ?luxS strain. The supernatant of EIB202 increased the biofilm formation ability of the ?luxS strain, which suggested that the luxS gene and its product LuxS enhanced biofilm formation in E. piscicida All results indicate that the LuxS/AI-2 quorum sensing system in E. piscicida promotes its pathogenicity through increasing a diverse array of physiological activities.
| S-EPMC7171233 | biostudies-literature
Project description:Bacteria have developed cell-to-cell communication mechanisms, termed quorum sensing (QS), that regulate bacterial gene expression in a cell population-dependent manner. Autoinducer-2 (AI-2), a class of QS signaling molecules derived from (4S)-4,5-dihydroxy-2,3-pentanedione (DPD), has been identified in both Gram-negative and Gram-positive bacteria. Despite considerable interest in the AI-2 QS system, the biomolecular communication used by distinct bacterial species still remains shrouded. Herein, we report the synthesis and evaluation of a new class of DPD analogues, C4-alkoxy-5-hydroxy-2,3-pentanediones, termed C4-alkoxy-HPDs. Remarkably, two of the analogues were more potent QS agonists than the natural ligand, DPD, in Vibrio harveyi. The findings presented extend insights into ligand-receptor recognition/signaling in the AI-2 mediated QS system.
| S-EPMC3438919 | biostudies-literature