A guide to virulence capabilities, as we currently understand them.

The Gram-negative pathogen causes a wide range of human infections. It causes particularly serious lung infections in individuals with cystic fibrosis, leading to high mortality rates. This pathogen is resistant to most known antibiotics and harbors a plethora of virulence factors, including lytic enzymes and serine proteases, that cause acute infection in host organisms.

Impact of a Wellness Leadership Intervention on the Empathy, Burnout, and Resting Heart Rate of Medical Faculty.

Objective: To evaluate the efficacy of a wellness leadership intervention for improving the empathy, burnout, and physiological stress of medical faculty leaders.

Participants And Methods: Participants were 49 medical faculty leaders (80% physicians, 20% basic scientists; 67% female). The 6-week course was evaluated with a 15-week longitudinal waitlist-control quasi-experiment from September 1, 2021, through December 20, 2021 (during the COVID-19 pandemic).

Thermoplastic polyurethane surface coated with polymer brushes for reduced protein and cell attachment.

The objective of this study was to coat negatively charged polymer brushes covalently onto the surface of thermoplastic polyurethane (TPU) using a simple conventional surface free-radical polymerization technique. The coated surfaces were assessed with contact angle, protein adsorption, cell adhesion and bacterial adhesion. Bovine serum albumin (BSA) and bovine fibrinogen (BFG) were used for protein adsorption evaluation.

Evaluating Metabolic Pathways and Biofilm Formation in Stenotrophomonas maltophilia.

Stenotrophomonas maltophilia has recently arisen as a prominent nosocomial pathogen because of its high antimicrobial resistance and ability to cause chronic respiratory infections. Often the infections are worsened by biofilm formation which enhances antibiotic tolerance. We have previously found that mutation of the gene, encoding the glycolytic enzyme phosphoglycerate mutase, impacts the formation of this biofilm on biotic and abiotic surfaces at early time points.

DNA alternate polymerase PolB mediates inhibition of type III secretion in Pseudomonas aeruginosa.

Opportunistic pathogen Pseudomonas aeruginosa uses a variety of virulence factors to cause acute and chronic infections. We previously found that alternate DNA polymerase gene polB inhibits P. aeruginosa pyocyanin production.

A self-cured glass-ionomer cement with improved antibacterial function and hardness.

A novel antimicrobial dental self-cured glass-ionomer cement has been developed and evaluated. Alumina filler particles were covalently coated with an antibacterial polymer and blended into a self-cured glass-ionomer cement formulation. Surface hardness and bacterial viability were used to evaluate the modified cements.

An antibacterial dental light-cured glass-ionomer cement with improved hardness.

An antibacterial dental light-cured glass-ionomer cement has been developed and evaluated. An antibacterial furanone derivative was synthesized and covalently attached onto the surface of alumina filler particles. The formed antibacterial fillers were then mixed into a light-curable glass-ionomer cement formulation.

Phosphoglycerate mutase affects Stenotrophomonas maltophilia attachment to biotic and abiotic surfaces.

Stenotrophomonas maltophilia biofilm formation is of increasing medical concern, particularly for lung infections. However, the molecular mechanisms facilitating the biofilm lifestyle in S. maltophilia are poorly understood.

An improved dental composite with potent antibacterial function.

A new BisGMA-based antibacterial dental composite has been formulated and evaluated. Compressive strength and bacterial viability were utilized to evaluate the formed composites. It was found that the new composite exhibited a significantly enhanced antibacterial function along with improved mechanical and physical properties.

Pseudomonas aeruginosa Magnesium Transporter MgtE Inhibits Type III Secretion System Gene Expression by Stimulating Transcription.

causes numerous acute and chronic opportunistic infections in humans. One of its most formidable weapons is a type III secretion system (T3SS), which injects powerful toxins directly into host cells. The toxins lead to cell dysfunction and, ultimately, cell death.

Statistical signatures of a targeted search by bacteria.

Chemoattractant gradients are rarely well-controlled in nature and recent attention has turned to bacterial chemotaxis toward typical bacterial food sources such as food patches or even bacterial prey. In environments with localized food sources reminiscent of a bacterium's natural habitat, striking phenomena-such as the volcano effect or banding-have been predicted or expected to emerge from chemotactic models. However, in practice, from limited bacterial trajectory data it is difficult to distinguish targeted searches from an untargeted search strategy for food sources.

Hydrodynamic Hunters.

The Gram-negative Bdellovibrio bacteriovorus (BV) is a model bacterial predator that hunts other bacteria and may serve as a living antibiotic. Despite over 50 years since its discovery, it is suggested that BV probably collides into its prey at random. It remains unclear to what degree, if any, BV uses chemical cues to target its prey.

GroEL/ES inhibitors as potential antibiotics.

We recently reported results from a high-throughput screening effort that identified 235 inhibitors of the Escherichia coli GroEL/ES chaperonin system [Bioorg. Med. Chem.

Expression of the lipopolysaccharide biosynthesis gene lpxD affects biofilm formation of Pseudomonas aeruginosa.

Bacterial biofilms are an important cause of nosocomial infections. Microorganisms such as Pseudomonas aeruginosa colonize biotic and abiotic surfaces leading to chronic infections that are difficult to eradicate. To characterize novel genes involved in biofilm formation, we identified the lpxD gene from a transposon-mutant library of P.

Involvement of stress-related genes polB and PA14_46880 in biofilm formation of Pseudomonas aeruginosa.

Chronic infections of Pseudomonas aeruginosa are generally established through production of biofilm. During biofilm formation, production of an extracellular matrix and establishment of a distinct bacterial phenotype make these infections difficult to eradicate. However, biofilm studies have been hampered by the fact that most assays utilize nonliving surfaces as biofilm attachment substrates.

Impact of alginate-producing Pseudomonas aeruginosa on alveolar macrophage apoptotic cell clearance.

Pseudomonas aeruginosa infection is a hallmark of lung disease in cystic fibrosis. Acute infection with P. aeruginosa profoundly inhibits alveolar macrophage clearance of apoptotic cells (efferocytosis) via direct effect of virulence factors.

Biofilm formation in the 96-well microtiter plate.

The microtiter plate (also called 96-well plate) assay for studying biofilm formation is a method which allows for the observation of bacterial adherence to an abiotic surface. In this assay, bacteria are incubated in vinyl "U"-bottom or other types of 96-well microtiter plates. Following incubation, planktonic bacteria are rinsed away, and the remaining adherent bacteria (biofilms) are stained with crystal violet dye, thus allowing visualization of the biofilm.

MgtE is a dual-function protein in Pseudomonas aeruginosa.

The opportunistic pathogen Pseudomonas aeruginosa causes a wide range of infections, including chronic biofilm infections in the lungs of individuals with cystic fibrosis. We previously found that the inner-membrane protein MgtE can function both as a magnesium transporter and a virulence modulator, although the exact mechanism governing these activities is unclear. To address this issue, we carried out an experimental characterization of P.

Antibiotic treatment of Pseudomonas aeruginosa biofilms stimulates expression of the magnesium transporter gene mgtE.

Pseudomonas aeruginosa is a Gram-negative opportunistic pathogen with the capacity to cause serious disease, including chronic biofilm infections in the lungs of cystic fibrosis (CF) patients. These infections are treated with high concentrations of antibiotics. Virulence modulation is an important tool utilized by P.

Eradication of Pseudomonas aeruginosa biofilms on cultured airway cells by a fosfomycin/tobramycin antibiotic combination.

Chronic biofilm formation by Pseudomonas aeruginosa in cystic fibrosis (CF) lungs is a major cause of morbidity and mortality for patients with CF. To gain insights into effectiveness of novel anti-infective therapies, the inhibitory effects of fosfomycin, tobramycin, and a 4:1 (wt/wt) fosfomycin/tobramycin combination (FTI) on Pseudomonas aeruginosa biofilms grown on cultured human CF-derived airway cells (CFBE41o-) were investigated. In preformed biofilms treated for 16 h with antibiotics, P.

Alcohol treatment enhances Staphylococcus aureus biofilm development.

Staphylococcus aureus forms pathogenic biofilms. Previous studies have indicated that ethanol supplementation during S. aureus biofilm formation results in increased biofilm formation and changes in gene expression.

Inquiry-based examination of chemical disruption of bacterial biofilms.

Inquiry-based instruction in the sciences has been demonstrated as a successful educational strategy to use for both high school and college science classrooms. As participants in the NSF Graduate STEM Fellows in K-12 Education (GK-12) Program, we were tasked with creating novel inquiry-based activities for high school classrooms. As a way to introduce microbiology, molecular biology, ecology, and human health to students, we created a laboratory activity involving formation of biofilms composed of environmental bacteria from pond water and investigation into the resistance of these biofilms to antimicrobial agents.

Co-culture models of Pseudomonas aeruginosa biofilms grown on live human airway cells.

Bacterial biofilms have been associated with a number of different human diseases, but biofilm development has generally been studied on non-living surfaces. In this paper, we describe protocols for forming Pseudomonas aeruginosa biofilms on human airway epithelial cells (CFBE cells) grown in culture. In the first method (termed the Static Co-culture Biofilm Model), P.

Polysaccharide capsule and sialic acid-mediated regulation promote biofilm-like intracellular bacterial communities during cystitis.

Uropathogenic Escherichia coli (UPEC) is the leading cause of urinary tract infections (UTIs). A murine UTI model has revealed an infection cascade whereby UPEC undergoes cycles of invasion of the bladder epithelium, intracellular proliferation in polysaccharide-containing biofilm-like masses called intracellular bacterial communities (IBC), and then dispersal into the bladder lumen to initiate further rounds of epithelial colonization and invasion. We predicted that the UPEC K1 polysaccharide capsule is a key constituent of the IBC matrix.