quorum sensing
Environmental Microbiology | SpotlightA Quorum Quenching Bacterial Isolate Contains Multiple Substrate-Inducible Genes Conferring Degradation of Diffusible Signal FactorDiffusible signal factor (DSF) represents a family of widely conserved quorum sensing signals involved in the regulation of virulence factor production in many Gram-negative bacterial pathogens. In this study, we developed a novel and efficient method for screening highly active DSF degradation microorganisms. With this method, we identified a bacterial isolate, Pseudomonas sp. strain HS-18, with a superb DSF degradation...
Microbial EcologyShort-Chain N-Acylhomoserine Lactone Quorum-Sensing Molecules Promote Periodontal Pathogens in In Vitro Oral BiofilmsDental plaque is omnipresent in healthy oral cavities and part of our commensal microbial colonization. At the same time, dental plaque is the cause of the most common human diseases, caries and gum disease. Dental plaque consists of billions of microbes attached to the surface of your teeth. Communication among these microbes is pivotal for development of these complex communities yet poorly studied in dental plaque. In the present...
GeomicrobiologyEffect of Quorum Sensing on the Ability of Desulfovibrio vulgaris To Form Biofilms and To Biocorrode Carbon Steel in Saline ConditionsSulfate-reducing bacteria (SRB) are considered key contributors to biocorrosion, particularly in saline environments. Biocorrosion imposes tremendous economic costs, and common approaches to mitigate this problem involve the use of toxic and hazardous chemicals (e.g., chlorine), which raise health and environmental safety concerns. Quorum-sensing inhibitors (QSIs) can be used as an alternative approach to inhibit biofilm formation and...
Environmental Microbiology | SpotlightCommunication within East Antarctic Soil BacteriaQuorum sensing, a type of bacterial communication, is widely known to regulate many processes, including those that confer a survival advantage. However, little is known about communication by bacteria residing within Antarctic soils. Employing a combination of bacterial biosensors, analytical techniques, and genome mining, we found a variety of Antarctic soil bacteria speaking a common language, via LuxI/LuxR-based quorum sensing, thus...
Genetics and Molecular BiologyPhenylacetyl Coenzyme A, Not Phenylacetic Acid, Attenuates CepIR-Regulated Virulence in Burkholderia cenocepaciaThe opportunistic pathogen Burkholderia cenocepacia uses a chemical signal process called quorum sensing (QS) to produce virulence factors. In B. cenocepacia, QS relies on the presence of the transcriptional regulator CepR which, upon binding QS signal molecules, activates virulence. In this work,...
Plant MicrobiologyVirulence Factor Identification in the Banana Pathogen Dickeya zeae MS2Dickeya zeae is an emerging banana soft rot pathogen in China. We used genome sequencing and annotation to create an inventory of potential virulence factors and virulence gene regulators encoded in Dickeya zeae MS2, a particularly virulent strain. We created mutations in several genes and tested...
PhysiologyQuorum Sensing Regulators AphA and OpaR Control Expression of the Operon Responsible for Biosynthesis of the Compatible Solute EctoineAccumulation of compatible solutes within the cell allows bacteria to maintain intracellular turgor pressure and prevent water efflux. De novo ectoine production is widespread among bacteria, and the ect operon encoding the biosynthetic enzymes is induced by increased salinity. Here, we demonstrate that the quorum sensing regulators AphA and OpaR integrate with the osmotic stress response pathway to control...
Genetics and Molecular BiologyPhysiological and Transcriptional Responses of Candida parapsilosis to Exogenous TyrosolCandida-secreted quorum-sensing molecules (i.e., farnesol and tyrosol) are key regulators in fungal physiology, which induce phenotypic adaptations, including morphological changes, altered biofilm formation, and synchronized expression of virulence factors. Moreover, they have a remarkable antifungal activity at supraphysiological concentrations. Limited data are available concerning the tyrosol-induced molecular and...
Public and Environmental Health MicrobiologyDisruption of Quorum Sensing and Virulence in Burkholderia cenocepacia by a Structural Analogue of the cis-2-Dodecenoic Acid SignalBurkholderia cenocepacia is an important opportunistic pathogen which can cause life-threatening infections in susceptible individuals, particularly in cystic fibrosis and immunocompromised patients. It usually employs two types of quorum sensing (QS) systems, including the cis-2-dodecenoic acid (BDSF) system and N-acyl homoserine lactone (AHL)...
Environmental MicrobiologyInterspecies Chemical Signaling in a Methane-Oxidizing Bacterial CommunityMethanotrophs are bacteria that sequester methane, a significant greenhouse gas, and thereby perform an important ecosystem function. Understanding the mechanisms by which these organisms interact in the environment may ultimately allow us to manipulate and to optimize this activity. Here we show that members of a genus of methane-oxidizing bacteria can be influenced by a chemical signal produced by a possibly competing species. This...