A pathogenicity island present only in highly pathogenic strains of Yersinia (Y. enterocolitica 1B, Y. pseudotuberculosis I and Y. pestis) has been identified on the chromosome of Yersinia spp. and has been designated High-Pathogenicity Island (HPI). The Yersinia HPI carries a cluster of genes involved in the biosynthesis, transport and regulation of the siderophore yersiniabactin. The major fu...

Hypervirulent Klebsiella pneumoniae is an emerging cause of community-acquired pyogenic liver abscess. First described in Asia, it is now increasingly recognized in Western countries, commonly afflicting those with Asian descent. This raises the question of genetic predisposition versus geospecific strain acquisition. We leveraged on the Antibiotics for Klebsiella Liver Abscess Syndrome Study (...

Klebsiella pneumoniae is a bacterial pathogen of worldwide importance and a significant contributor to multiple disease presentations associated with both nosocomial and community acquired disease. ATCC 43816 is a well-studied K. pneumoniae strain which is capable of causing an acute respiratory disease in surrogate animal models. In this study, we performed sequencing of the ATCC 43816 genome ...

Phylogenetic relationships, virulence factors, alone and in specific combinations, and virulence in a rat meningitis model were examined among 132 isolates of Escherichia coli neonatal meningitis from France and North America. Isolates belonging to phylogenetic groups A (n=11), D (n=20), and B2 (n=99) had similar high prevalence rates of the siderophores aerobactin and yersiniabactin and the K1...

The increasing prevalence of KPC-producing Klebsiella pneumoniae strains in clinical settings has been largely attributed to dissemination of organisms of specific multilocus sequence types, such as ST258 and ST11. Compared with the ST258 clone, which is prevalent in North America and Europe, ST11 is common in China but information regarding its genetic features remains scarce. In this study, w...

One prerequisite for the virulence of Yersinia pestis, causative agent of bubonic plague, is the yersiniabactin (Ybt) siderophore-dependent iron transport system that is encoded within a high-pathogenicity island (HPI) within the pgm locus of the Y. pestis chromosome. Several gene products within the HPI have demonstrated functions in the synthesis or transport of Ybt. Here we examine the roles...

Escherichia coli and other Enterobacteriaceae are among the most common pathogens of the human urinary tract. Among the genetic gains of function associated with urinary E. coli isolates is the Yersinia high pathogenicity island (HPI), which directs the biosynthesis of yersiniabactin (Ybt), a virulence-associated metallophore. Using a metabolomics approach, we found that E. coli and other Enter...

This work reports the utilization of an in vivo expression technology system to identify in vivo-induced (ivi) genes in Yersinia ruckeri after determination of the conditions needed for its selection in fish. Fourteen clones were selected, and the cloned DNA fragments were analyzed after partial sequencing. In addition to sequences with no significant similarity, homology with genes encoding pr...

Nasal colonization by both gram-positive and gram-negative pathogens induces expression of the innate immune protein lipocalin 2 (Lcn2). Lcn2 binds and sequesters the iron-scavenging siderophore enterobactin (Ent), preventing bacterial iron acquisition. In addition, Lcn2 bound to Ent induces release of IL-8 from cultured respiratory cells. As a countermeasure, pathogens of the Enterobacteriacea...