New tools to monitor infection and biofilms in .

Introduction: Antimicrobial resistance is a growing health problem. Pseudomonas aeruginosa is a pathogen of major concern because of its multidrug resistance and global threat, especially in health-care settings. The pathogenesis and drug resistance of depends on its ability to form biofilms, making infections chronic and untreatable as the biofilm protects against antibiotics and host immunity.

An in vitro assessment of bacterial transfer by products used in debridement.

Objective: The aim of this in vitro study was to investigate the transfer of viable Pseudomonas aeruginosa biofilm microorganisms following treatment with debridement tools.

Method: The level of viable biofilm microorganisms transferred by debridement tools was compared following treatment that reflected the clinical practice of each product.

Results: A significant level of microorganism transfer was seen in response to the mechanical debridement tool.

Effectiveness of a non-medicated wound dressing on attached and biofilm encased bacteria: laboratory and clinical evidence.

Objective: The objective of this study was to evaluate the ability of a non medicated, hydro-responsive wound dressing (HRWD) to effectively aid in the removal of bacteria known to reside (and cause infections) within the wound environment.

Method: A series of in vitro studies were undertaken using Staphylococcus aureus and Pseudomonas aeruginosa biofilms to evaluate the capabilities of the HRWD to disrupt and disperse biofilms.

Results: Biofilms can be broken up and dispersed by HRWD and both Staphylococcus aureus and Pseudomonas aeruginosa numbers can be reduced by a greater than log reduction in the presence of HRWD.

The multiple antibiotic resistance operon of enteric bacteria controls DNA repair and outer membrane integrity.

The multiple antibiotic resistance (mar) operon of Escherichia coli is a paradigm for chromosomally encoded antibiotic resistance in enteric bacteria. The locus is recognised for its ability to modulate efflux pump and porin expression via two encoded transcription factors, MarR and MarA. Here we map binding of these regulators across the E.

Development of a new fluorescent reporter:operator system: location of AraC regulated genes in Escherichia coli K-12.

Background: In bacteria, many transcription activator and repressor proteins regulate multiple transcription units that are often distally distributed on the bacterial genome. To investigate the subcellular location of DNA bound proteins in the folded bacterial nucleoid, fluorescent reporters have been developed which can be targeted to specific DNA operator sites. Such Fluorescent Reporter-Operator System (FROS) probes consist of a fluorescent protein fused to a DNA binding protein, which binds to an array of DNA operator sites located within the genome.

Tracking Low-Copy Transcription Factors in Living Bacteria: The Case of the lac Repressor.

Transcription factors control the expression of genes by binding to specific sites in DNA and repressing or activating transcription in response to stimuli. The lac repressor (LacI) is a well characterized transcription factor that regulates the ability of bacterial cells to uptake and metabolize lactose. Here, we study the intracellular mobility and spatial distribution of LacI in live bacteria using photoactivated localization microscopy combined with single-particle tracking.

DNA recognition by Escherichia coli CbpA protein requires a conserved arginine-minor-groove interaction.

Curved DNA binding protein A (CbpA) is a co-chaperone and nucleoid associated DNA binding protein conserved in most γ-proteobacteria. Best studied in Escherichia coli, CbpA accumulates to >2500 copies per cell during periods of starvation and forms aggregates with DNA. However, the molecular basis for DNA binding is unknown; CbpA lacks motifs found in other bacterial DNA binding proteins.

Chromosome position effects on gene expression in Escherichia coli K-12.

In eukaryotes, the location of a gene on the chromosome is known to affect its expression, but such position effects are poorly understood in bacteria. Here, using Escherichia coli K-12, we demonstrate that expression of a reporter gene cassette, comprised of the model E. coli lac promoter driving expression of gfp, varies by ∼300-fold depending on its precise position on the chromosome.