biofilm
Environmental Microbiology | SpotlightBiofilm Formation and Synthesis of Antimicrobial Compounds by the Biocontrol Agent Bacillus velezensis QST713 in an Agaricus bisporus Compost MicromodelBiocontrol agents are increasingly used to replace chemical pesticides to prevent crop diseases. In the button mushroom field in France, the use of Bacillus velezensis QST713 as a biocontrol agent against the green mold Trichoderma aggressivum has been shown to be efficient. However, the biocontrol...
Environmental MicrobiologyBiofilm-Constructing Variants of Paraburkholderia phytofirmans PsJN Outcompete the Wild-Type Form in Free-Living and Static Conditions but Not In PlantaParaburkholderia phytofirmans strain PsJN is a well-studied plant-associated bacterium known to induce resistance against biotic and abiotic stresses. In this work, we described the spontaneous appearance of mucoid variants in PsJN from static cultures. We showed that the conversion from the wild-type (WT) form to variants (V) correlates with an overproduction of EPS...
Genetics and Molecular BiologyAn Osmoregulatory Mechanism Operating through OmpR and LrhA Controls the Motile-Sessile Switch in the Plant Growth-Promoting Bacterium Pantoea alhagiMany motile bacterial populations form surface-attached biofilms in response to specific environmental cues, including osmotic stress in a range of natural and host-related systems. However, cross talk between bacterial osmosensing, swimming, and biofilm formation regulatory networks is not fully understood. Here, we report that the pleiotropic regulator LrhA in Pantoea alhagi is involved in the regulation of flagellar motility...
PhysiologyCell Aggregation and Aerobic Respiration Are Important for Zymomonas mobilis ZM4 Survival in an Aerobic Minimal MediumThe bacterium Zymomonas mobilis is best known for its anaerobic fermentative lifestyle, in which it converts glucose into ethanol at a yield surpassing that of yeast. However, Z. mobilis also has an aerobic lifestyle, which has confounded researchers with its attributes of poor growth, accumulation...
Genetics and Molecular BiologyMethionine Limitation Impairs Pathogen Expansion and Biofilm Formation CapacityNew antibiotics that attack novel targets are needed to circumvent widespread resistance to conventional drugs. Bacterial anabolic pathways, such as the enzymes for biosynthesis of the essential amino acid methionine, have been proposed as potential targets. However, the eligibility of enzymes in these pathways as drug targets is unclear because metabolites might be acquired from the environment to overcome inhibition. We investigated...
Environmental MicrobiologyTwo Novel Bacteriophages Improve Survival in Galleria mellonella Infection and Mouse Acute Pneumonia Models Infected with Extensively Drug-Resistant Pseudomonas aeruginosaIn this study, two novel P. aeruginosa phages, Bϕ-R656 and Bϕ-R1836, were evaluated in vitro, in silico, and in vivo for therapeutic efficacy and safety as an alternative antibacterial agent to control XDR-PA strains collected from pneumonia patients. Both phages exhibited potent bacteriolytic activity and greatly improved survival in...
Genetics and Molecular BiologyThe Edwardsiella piscicida Type III Translocon Protein EseC Inhibits Biofilm Formation by Sequestering EseEEdwardsiella piscicida, previously known as Edwardsiella tarda, is a Gram-negative intracellular pathogen that mainly infects fish. The type III secretion system (T3SS) plays a pivotal role in its pathogenesis. The T3SS translocon protein EseB is required for the assembly of filamentous appendages...
Public and Environmental Health MicrobiologyChlorine and Monochloramine Disinfection of Legionella pneumophila Colonizing Copper and Polyvinyl Chloride Drinking Water BiofilmsMicrobial regrowth within building water systems are promoted by water stagnation, low disinfectant residual, high surface-to-volume ratio, amenable growth temperatures, and colonization of drinking water biofilms. Moreover, biofilms provide protection from environmental stresses, access to higher levels of nutrients, and opportunities for symbiotic interactions with other microbes. Disinfectant efficacy information is historically...
Public and Environmental Health Microbiology | SpotlightLoss of Function in Escherichia coli Exposed to Environmentally Relevant Concentrations of Benzalkonium ChlorideExposure to very low concentrations of biocides in the environment is a poorly understood risk factor for antimicrobial resistance. Repeated exposure to trace levels of the biocide benzalkonium chloride (BAC) resulted in loss of function (motility) and a general reduction in bacterial fitness but relatively minor decreases in susceptibility. These changes were accompanied by widespread changes in the...
Environmental MicrobiologyIron Homeostasis in Bacillus subtilis Requires Siderophore Production and Biofilm FormationIron acquisition is of fundamental importance for microorganisms, since this metal is generally poorly bioavailable under natural conditions. In the environment, most bacteria are found tightly packed within multicellular communities named biofilms. Here, using the soil Gram-positive bacterium Bacillus subtilis, we show that biofilm formation and the production of...