Phenylacetic acid metabolic genes are associated with dominant circulating clone 1.

Unlabelled: (MAB) causes lung infections in people with cystic fibrosis (pwCF), and infecting strains show significant genetic variability both between and within individuals. MAB isolates can be divided into dominant clonal clusters (DCCs) or non-clustering groups and can present as smooth or rough colonies on agar plates. Both DCCs and the rough colony morphology have been linked to increased pathogenicity, but the mechanisms are unclear.

Ignoring social distancing: advances in understanding multi-species bacterial interactions.

Almost every ecosystem on this planet is teeming with microbial communities made of diverse bacterial species. At a reductionist view, many of these bacteria form pairwise interactions, but, as the field of view expands, the neighboring organisms and the abiotic environment can play a crucial role in shaping the interactions between species. Over the years, a strong foundation of knowledge has been built on isolated pairwise interactions between bacteria, but now the field is advancing toward understanding how cohabitating bacteria and natural surroundings affect these interactions.

Predicting toxins found in toxin-antitoxin systems with a role in host-induced Burkholderia pseudomallei persistence.

Burkholderia pseudomallei (Bpm) is a bacterial pathogen that causes Melioidosis, a disease with up to 40% mortality and an infection relapse of 15-23% despite antibiotic treatment. Ineffective clearance of Bpm by antibiotics is believed to be due to persistence, a hibernation-like survival mechanism modulated, in part, by toxin-antitoxin systems (TAS). Several organisms possess a repertoire of TASs but defining environmental cues eliciting their activity is hindered by laborious in vitro experiments, especially when there are many toxins with redundant function.

Evaluating the role of Burkholderia pseudomallei K96243 toxins BPSS0390, BPSS0395, and BPSS1584 in persistent infection.

Burkholderia pseudomallei is the causative agent of melioidosis, a disease with a mortality rate of up to 40% even with treatment. Despite the ability of certain antibiotics to control initial infection, relapse occurs in treated patients. The inability of antibiotics to clear this bacterial infection is in part due to persistence, an evasion mechanism against antibiotics and the effect of host defenses.

Burkholderia pseudomallei Δ Δ Live Attenuated Vaccine Strain Elicits Full Protective Immunity against Aerosolized Melioidosis Infection.

is a Gram-negative facultative intracellular bacterium and the causative agent of melioidosis, a severe infectious disease found throughout the tropics. This organism is closely related to , the etiological agent of glanders disease which primarily affects equines. These two pathogenic bacteria are classified as Tier 1 select agents due to their amenability to aerosolization, limited treatment options, and lack of an effective vaccine.

Increased Mortality in Mice following Immunoprophylaxis Therapy with High Dosage of Nicotinamide in Persistent Infections.

Bacterial persistence, known as noninherited antibacterial resistance, is a factor contributing to the establishment of long-lasting chronic bacterial infections. In this study, we examined the ability of nicotinamide (NA) to potentiate the activity of different classes of antibiotics against persister cells. Here we demonstrate that addition of NA in models of infection resulted in a significant depletion of the persister population in response to various classes of antibiotics.

Evaluating New Compounds to Treat Infections.

is the causative agent of melioidosis, a disease that requires long-term treatment regimens with no assurance of bacterial clearance. Clinical isolates are intrinsically resistant to most antibiotics and in recent years, isolates have been collected that display resistance to frontline drugs. With the expanding global burden of , there is a need to identify new compounds or improve current treatments to reduce risk of relapse.

Development of Subunit Vaccines That Provide High-Level Protection and Sterilizing Immunity against Acute Inhalational Melioidosis.

, the etiologic agent of melioidosis, causes severe disease in humans and animals. Diagnosis and treatment of melioidosis can be challenging, and no licensed vaccines currently exist. Several studies have shown that this pathogen expresses a variety of structurally conserved protective antigens that include cell surface polysaccharides and cell-associated and cell-secreted proteins.

From In silico Protein Epitope Density Prediction to Testing Escherichia coli O157:H7 Vaccine Candidates in a Murine Model of Colonization.

Enterohemorrhagic Escherichia coli (EHEC) O157:H7 is a leading cause of foodborne illnesses worldwide and is a common serotype linked to hemorrhagic colitis and an important cause of hemolytic uremic syndrome (HUS). Treatment of EHEC O157:H7 infections is complicated, as antibiotics can exacerbate Shiga toxin (Stx) production and lead to more severe symptoms including HUS. To date, no vaccines have been approved for human use, exposing a void in both treatment and prevention of EHEC O157:H7 infections.

Burkholderia cepacia Complex Vaccines: Where Do We Go from here?

Burkholderia comprises a wide variety of environmental Gram-negative bacteria. Burkholderia cepacia complex (Bcc) includes several Burkholderia species that pose a health hazard as they are able to cause respiratory infections in patients with chronic granulomatous disease and cystic fibrosis. Due to the intrinsic resistance to a wide array of antibiotics and naturally occurring immune evasion strategies, treatment of Bcc infections often proves to be unsuccessful.

The Role of Long Polar Fimbriae in Escherichia coli O104:H4 Adhesion and Colonization.

A renewed interest in Shiga toxin-producing Escherichia coli (STEC) strains was sparked due to the appearance of an outbreak in 2011, causing 3,816 diarrheal cases and some deaths in Europe. The causative strain was classified as enteroaggregative E. coli of serotype O104:H4 that had acquired Shiga toxin genes.

Finding Regulators Associated with the Expression of the Long Polar Fimbriae in Enteropathogenic Escherichia coli.

Unlabelled: Enteropathogenic Escherichia coli (EPEC) is a human pathogen that requires initial adhesion to the intestine in order to cause disease. Multiple adhesion factors have been identified in E. coli strains, among them the long polar fimbriae (Lpf), a colonization factor associated with intestinal adhesion.

The IbeA invasin of adherent-invasive Escherichia coli mediates interaction with intestinal epithelia and macrophages.

Adherent-invasive Escherichia coli (AIEC) pathogroup isolates are a group of isolates from the intestinal mucosa of Crohn's disease patients that can invade intestinal epithelial cells (IECs) or macrophages and survive and/or replicate within. We have identified the ibeA gene in the genome of AIEC strain NRG857c and report the contribution of IbeA to the interaction of AIEC with IECs and macrophages and colonization of the mouse intestine. An ibeA deletion mutant strain (NRG857cΔibeA) was constructed, and the in vitro effect on AIEC adhesion and invasion of nonpolarized and polarized Caco-2 cells, the adhesion and transcytosis of M-like cells, the intracellular survival in THP-1 macrophages, and the contribution to intestinal colonization of the CD-1 murine model of infection were evaluated.