biofilms
Research Article | Molecular Biology and PhysiologyCross Talk between Chemosensory Pathways That Modulate Chemotaxis and Biofilm FormationIn many bacteria, two or more homologous chemosensory pathways control several cellular functions, such as motility and gene regulation, in response to changes in the cell’s microenvironment. Cross talk between signal transduction systems is poorly understood; while generally it is considered to be undesired, in some instances it might be beneficial for coregulation of complex behaviors. We demonstrate that several receptors from the...
Research Article | Ecological and Evolutionary ScienceCompetition in Biofilms between Cystic Fibrosis Isolates of Pseudomonas aeruginosa Is Shaped by R-PyocinsA major clinical problem caused by Pseudomonas aeruginosa, is chronic biofilm infection of the lungs in individuals with cystic fibrosis (CF). Epidemic P. aeruginosa strains dominate and displace others during CF infection, but these intraspecies interactions remain poorly understood. Here we...
Research Article | Molecular Biology and PhysiologyPhysical Determinants of Amyloid Assembly in Biofilm FormationBiofilms are generated by bacteria, embedded in the formed extracellular matrix. The biofilm's function is to improve the survival of a bacterial colony through, for example, increased resistance to antibiotics or other environmental stresses. Proteins secreted by the bacteria act as a major structural component of this extracellular matrix, as they self-assemble into highly stable amyloid fibrils, making the biofilm very difficult to...
Research Article | Molecular Biology and PhysiologyMatrix Polysaccharides and SiaD Diguanylate Cyclase Alter Community Structure and Competitiveness of Pseudomonas aeruginosa during Dual-Species Biofilm Development with Staphylococcus aureusBacteria in natural and engineered environments form biofilms that include many different species. Microorganisms rely on a number of different strategies to manage social interactions with other species and to access resources, build biofilm consortia, and optimize growth. For example, Pseudomonas...
- Research Article | Molecular Biology and PhysiologyChlorate Specifically Targets Oxidant-Starved, Antibiotic-Tolerant Populations of Pseudomonas aeruginosa Biofilms
The anaerobic growth and survival of bacteria are often correlated with physiological tolerance to conventional antibiotics, motivating the development of novel strategies targeting pathogens in anoxic environments. A key challenge is to identify drug targets that are specific to this metabolic state. Chlorate is a nontoxic compound that can be reduced to toxic chlorite by a widespread enzyme of anaerobic metabolism. We tested the...
- Research Article | Molecular Biology and PhysiologyThe Pseudomonas aeruginosa Complement of Lactate Dehydrogenases Enables Use of d- and l-Lactate and Metabolic Cross-Feeding
Lactate is thought to serve as a carbon and energy source during chronic infections. Sites of bacterial colonization can contain two enantiomers of lactate: the l-form, generally produced by the host, and the d-form, which is usually produced by bacteria, including the pulmonary pathogen Pseudomonas aeruginosa. Here, we...
- Research ArticleRemoval of a Membrane Anchor Reveals the Opposing Regulatory Functions of Vibrio cholerae Glucose-Specific Enzyme IIA in Biofilms and the Mammalian Intestine
The V. cholerae phosphoenolpyruvate phosphotransferase system (PTS) is a well-conserved, multicomponent phosphotransfer cascade that regulates cellular physiology and virulence in response to nutritional signals. Glucose-specific enzyme IIA (EIIAGlc), a component of the PTS, is a master regulator that coordinates bacterial metabolism, nutrient uptake, and...
- Research ArticleEnvironmental Calcium Initiates a Feed-Forward Signaling Circuit That Regulates Biofilm Formation and Rugosity in Vibrio vulnificus
The second messenger c-di-GMP is a key regulator of bacterial physiology. The V. vulnificus genome encodes nearly 100 proteins predicted to make, break, and bind c-di-GMP. However, relatively little is known regarding the environmental signals that regulate c-di-GMP levels and biofilm formation in V. ...