Learn More
Conventional wisdom regarding mechanisms of bacterial pathogenesis holds that pathogens arise by external acquisition of distinct virulence factors, whereas determinants shared by pathogens and commensals are considered to be functionally equivalent and have been ignored as genes that could become adapted specifically for virulence. It is shown here,(More)
Pathogens of the genus Klebsiella have been classified into distinct capsular (K) types for nearly a century. K typing of Klebsiella species still has important applications in epidemiology and clinical microbiology, but the serological method has strong practical limitations. Our objective was to evaluate the sequencing of wzi, a gene conserved in all(More)
The degree to which molecular epidemiology reveals information about the sources and transmission patterns of an outbreak depends on the resolution of the technology used and the samples studied. Isolates of Escherichia coli O104:H4 from the outbreak centered in Germany in May-July 2011, and the much smaller outbreak in southwest France in June 2011, were(More)
In vitro and in vivo models were used to investigate the role of capsule on the virulence of Klebsiella pneumoniae. We showed that capsule expression reduces dramatically the ability of the K. pneumoniae to bind to epithelial cells when compared to its non-capsulated variant. The presence/absence of capsule had no effect on the colonization of the(More)
Klebsiella pneumoniae is an important opportunistic pathogen and a frequent cause of nosocomial infections. We have characterized a K. pneumoniae strain responsible for a series of critical infections in an intensive care unit over a two-year period. The strain was found to be remarkably thermotolerant providing a conceivable explanation of its persistence(More)
Klebsiella pneumoniae is recognized as an important gram-negative opportunistic pathogen. The ability of bacteria to adhere to host structures is considered essential for the development of infections; however, few studies have examined the influence of adhesion factors on K. pneumoniae virulence. In this study, we cloned and characterized the type 1(More)
UNLABELLED Highly invasive, community-acquired Klebsiella pneumoniae infections have recently emerged, resulting in pyogenic liver abscesses. These infections are caused by hypervirulent K. pneumoniae (hvKP) isolates primarily of capsule serotype K1 or K2. Hypervirulent K1 isolates belong to clonal complex 23 (CC23), indicating that this clonal lineage has(More)
Mutant screens and transcriptome studies led us to consider whether the metabolism of glucose polymers, i.e., maltose, maltodextrin, and glycogen, is important for Escherichia coli colonization of the intestine. By using the streptomycin-treated mouse model, we found that catabolism of the disaccharide maltose provides a competitive advantage in vivo to(More)
OBJECTIVES AND METHODS Klebsiella pneumoniae is a nosocomial pathogen and is considered the most common gram-negative bacterium that exhibits multiple antimicrobial resistances. In this study, the transfer of antimicrobial resistance genes from the clinical multiresistant K. pneumoniae MGH75875 isolate was assessed in vitro and in vivo in an intestinal(More)
Enteroaggregative Escherichia coli (EAEC) is an important cause of diarrhea worldwide. We analyzed 17 Danish EAEC strains, isolated in the course of a case control study, for phenotypic and genotypic properties. The strains belonged to at least 14 different serotypes. Using PCR to investigate the prevalence of various putative virulence genes, we found that(More)