Escherichia coli
Bacterial InfectionsSuccess of Escherichia coli O25b:H4 Sequence Type 131 Clade C Associated with a Decrease in VirulenceEscherichia coli O25b:H4 sequence type 131 (ST131), which is resistant to fluoroquinolones and which is a producer of CTX-M-15, is globally one of the major extraintestinal pathogenic E. coli (ExPEC) lineages. Phylogenetic analyses showed that multidrug-resistant ST131 strains belong to clade C,...
Bacterial InfectionsAggregative Adherence Fimbriae II of Enteroaggregative Escherichia coli Are Required for Adherence and Barrier Disruption during Infection of Human ColonoidsSymptomatic and asymptomatic infection with the diarrheal pathogen enteroaggregative Escherichia coli (EAEC) is associated with growth faltering in children in developing settings. The mechanism of this association is unknown, emphasizing a need for better understanding of the interactions between EAEC and the human gastrointestinal mucosa. In this study, we...
Bacterial Infections | SpotlightA Rare Opportunist, Morganella morganii, Decreases Severity of Polymicrobial Catheter-Associated Urinary Tract InfectionCatheter-associated urinary tract infections (CAUTIs) are common hospital-acquired infections and frequently polymicrobial, which complicates effective treatment. However, few studies experimentally address the consequences of polymicrobial interactions within the urinary tract, and the clinical significance of polymicrobial bacteriuria is not fully understood.
Molecular PathogenesisBimodal Response to Shiga Toxin 2 Subtypes Results from Relatively Weak Binding to the Target CellThere are two major antigenic forms of Shiga toxin (Stx), Stx1 and Stx2, which bind the same receptor and act on the same target but nonetheless differ in potency. Stx1a is more toxic to cultured cells, but Stx2 subtypes are more potent in animal models. To understand this phenomenon in cultured cells, we used a system that combines flow cytometry with a fluorescent reporter to monitor the Stx-induced inhibition of protein synthesis in...
Fungal and Parasitic InfectionsEntamoeba histolytica Interaction with Enteropathogenic Escherichia coli Increases Parasite Virulence and Inflammation in AmebiasisEpidemiological studies suggest frequent association of enteropathogenic bacteria with Entamoeba histolytica during symptomatic infection. In this study, we sought to determine if the interaction with enteropathogenic (EPEC) or nonpathogenic Escherichia coli (strain DH5α) could modify the virulence...
MinireviewTaming the Beast: Interplay between Gut Small Molecules and Enteric PathogensThe overuse of antibiotics has led to the evolution of drug-resistant bacteria that are becoming increasingly dangerous to human health. According to the Centers for Disease Control and Prevention, antibiotic-resistant bacteria cause at least 2 million illnesses and 23,000 deaths in the United States annually. Traditionally, antibiotics are bactericidal or bacteriostatic agents that place selective pressure on bacteria, leading to the...
Bacterial InfectionsBacterial Microcompartment-Mediated Ethanolamine Metabolism in Escherichia coli Urinary Tract InfectionUrinary tract infections (UTIs) are common and in general are caused by intestinal uropathogenic Escherichia coli (UPEC) ascending via the urethra. Microcompartment-mediated catabolism of ethanolamine, a host cell breakdown product, fuels the competitive overgrowth of intestinal E. coli, both...
Molecular PathogenesisLoss of Trefoil Factor 2 Sensitizes Rat Pups to Systemic Infection with the Neonatal Pathogen Escherichia coli K1Gastrointestinal (GI) colonization of 2-day-old (P2) rat pups with Escherichia coli K1 results in translocation of the colonizing bacteria across the small intestine, bacteremia, and invasion of the meninges, with animals frequently succumbing to lethal infection. Infection, but not colonization, is strongly age dependent; pups become progressively less susceptible to...
Molecular PathogenesisShiga Toxin Type 1a (Stx1a) Reduces the Toxicity of the More Potent Stx2a In Vivo and In VitroShiga toxin (Stx)-producing Escherichia coli (STEC) causes foodborne outbreaks of bloody diarrhea. There are two major types of immunologically distinct Stxs: Stx1a and Stx2a.
Host Response and InflammationDiffusely Adherent Escherichia coli Strains Isolated from Healthy Carriers Suppress Cytokine Secretions of Epithelial Cells Stimulated by Inflammatory SubstancesDiarrheagenicity of diffusely adherent Escherichia coli (DAEC) remains controversial. Previously, we found that motile DAEC strains isolated from diarrheal patients induced high levels of interleukin 8 (IL-8) secretion via Toll-like receptor 5 (TLR5).