The Galleria mellonella larvae as an in vivo model for evaluation of Shigella virulence.

Shigella spp. causing bacterial diarrhea and dysentery are human enteroinvasive bacterial pathogens that are orally transmitted through contaminated food and water and cause bacillary dysentery. Although natural Shigella infections are restricted to humans and primates, several smaller animal models are used to analyze individual steps in pathogenesis.

Crosstalk between the HpArsRS two-component system and HpNikR is necessary for maximal activation of urease transcription.

Helicobacter pylori NikR (HpNikR) is a nickel dependent transcription factor that directly regulates a number of genes in this important gastric pathogen. One key gene that is regulated by HpNikR is ureA, which encodes for the urease enzyme. In vitro DNA binding studies of HpNikR with the ureA promoter (PureA ) previously identified a recognition site that is required for high affinity protein/DNA binding.

AB5075, a Highly Virulent Isolate of Acinetobacter baumannii, as a Model Strain for the Evaluation of Pathogenesis and Antimicrobial Treatments.

Unlabelled: Acinetobacter baumannii is recognized as an emerging bacterial pathogen because of traits such as prolonged survival in a desiccated state, effective nosocomial transmission, and an inherent ability to acquire antibiotic resistance genes. A pressing need in the field of A. baumannii research is a suitable model strain that is representative of current clinical isolates, is highly virulent in established animal models, and can be genetically manipulated.

Prolonged latency to CNS-O2 toxicity induced by heat acclimation in rats is associated with increased antioxidative defenses and metabolic energy preservation.

We have previously shown that heat acclimation provides protection against central nervous system oxygen toxicity (CNS-OT). This was well correlated with increased levels of heat shock protein 72 (HSP72). We now examine other antioxidative defenses against CNS-OT that are correlated with heat acclimation.

The oligo-acyl lysyl antimicrobial peptide C₁₂K-2β₁₂ exhibits a dual mechanism of action and demonstrates strong in vivo efficacy against Helicobacter pylori.

Helicobacter pylori has developed antimicrobial resistance to virtually all current antibiotics. Thus, there is a pressing need to develop new anti-H. pylori therapies.

The Helicobacter pylori Ferric Uptake Regulator (Fur) is essential for growth under sodium chloride stress.

Epidemiological data and animal models indicate that Helicobacter pylori and dietary NaCl have a synergistic ill effect on gastric maladies. Here we show that the Ferric Uptake Regulator (Fur), which is a crucial regulatory factor required for H. pylori colonization, is essential for growth in the presence of high NaCl concentrations.

Mutagenesis of conserved amino acids of Helicobacter pylori fur reveals residues important for function.

The ferric uptake regulator (Fur) of the medically important pathogen Helicobacter pylori is unique in that it has been shown to function as a repressor both in the presence of an Fe2+ cofactor and in its apo (non-Fe2+-bound) form. However, virtually nothing is known concerning the amino acid residues that are important for Fur functioning. Therefore, mutations in six conserved amino acid residues of H.

Helicobacter pylori apo-Fur regulation appears unconserved across species.

The Ferric Uptake Regulator (Fur) is a transcriptional regulator that is conserved across a broad number of bacterial species and has been shown to regulate expression of iron uptake and storage genes. Additionally, Fur has been shown to be an important colonization factor of the gastric pathogen Helicobacter pylori. In H.

In vitro antibacterial activity of acyl-lysyl oligomers against Helicobacter pylori.

The gastric pathogen Helicobacter pylori has developed resistance to virtually all current antibiotics; thus, there is a pressing need to develop new anti-H. pylori therapies. The goal of this work was to evaluate the antibacterial effect of oligo-acyl-lysyl (OAK) antimicrobial peptidomimetics to determine if they might represent alternatives to conventional antibiotic treatment of H.

A single nucleotide change affects fur-dependent regulation of sodB in H. pylori.

Helicobacter pylori is a significant human pathogen that has adapted to survive the many stresses found within the gastric environment. Superoxide Dismutase (SodB) is an important factor that helps H. pylori combat oxidative stress.

The association between non-biting midges and Vibrio cholerae.

Vibrio cholerae is a natural inhabitant of aquatic ecosystems, yet its interactions within this habitat are poorly understood. Here we describe the current knowledge on the interaction of V. cholerae with one group of co-inhabitants, the chironomids.

Sodium chloride affects Helicobacter pylori growth and gene expression.

Epidemiological evidence links high-salt diets and Helicobacter pylori infection with increased risk of developing gastric maladies. The mechanism by which elevated sodium chloride content causes these manifestations is unclear. Here we characterize the response of H.

Expanding the Helicobacter pylori genetic toolbox: modification of an endogenous plasmid for use as a transcriptional reporter and complementation vector.

Helicobacter pylori is an important human pathogen. However, the study of this organism is often limited by a relative shortage of genetic tools. In an effort to expand the methods available for genetic study, an endogenous H.

Balancing the double-edged sword: metal ion homeostasis and the ulcer bug.

The essential nature of many metals is counterbalanced by the toxic effect that they can exert on both the eukaryotic and prokaryotic cell when not properly controlled. As such, virtually all organisms have developed regulatory systems that are required to maintain metal ion homeostasis. Helicobacter pylori is arguably the most successful bacterial pathogen in the world; the bacterium colonizes more than 50% of the world's population.

Vibrio cholerae strain typing and phylogeny study based on simple sequence repeats.

Vibrio cholerae is the etiological agent of cholera. Its natural reservoir is the aquatic environment. To date, practical typing of V.

Iron and pH homeostasis intersect at the level of Fur regulation in the gastric pathogen Helicobacter pylori.

Helicobacter pylori persistently colonizes the stomach of the majority of the world's population and is a tremendous medical burden due to its causal role in diverse gastric maladies. Since the stomach is a constantly changing environment, successful colonization of H. pylori within this niche requires regulation of bacterial gene expression to cope with the environmental fluctuations.

Adhesion of Vibrio cholerae to granular starches.

Cholera is a severe diarrheal disease caused by specific serogroups of Vibrio cholerae that are pathogenic to humans. Cholera can become epidemic and deadly without adequate medical care. Appropriate rehydration therapy can reduce the mortality rate from as much as 50% of the affected individuals to <1%.

Adult non-biting midges: possible windborne carriers of Vibrio cholerae non-O1 non-O139.

Vibrio cholerae is a waterborne bacterium native to the aquatic environment. There are over 200 known serogroups yet only two cause cholera pandemics in humans. Direct contact of human sewage with drinking water, sea-born currents and marine transportation, represent modes of dissemination of the bacteria and thus the disease.

Vibrio cholerae hemagglutinin/protease degrades chironomid egg masses.

Cholera is a severe diarrheal disease caused by specific serogroups of Vibrio cholerae that are pathogenic to humans. The disease does not persist in a chronic state in humans or animals. The pathogen is naturally present as a free-living organism in the environment.

Heat acclimation prolongs the time to central nervous system oxygen toxicity in the rat. Possible involvement of HSP72.

Oxygen toxicity of the central nervous system (CNS-OT) can occur during diving with oxygen-enriched gas mixtures, or during hyperbaric medical treatment. CNS-OT is characterised by convulsions and sudden loss of consciousness, which may be fatal in diving. Heat acclimation is known to provide cross-tolerance to various forms of stress in different organs, including the brain.