FdeC, a Novel Broadly Conserved Escherichia coli Adhesin Eliciting Protection against Urinary Tract Infections

Novartis Vaccines and Diagnostics Srl, Siena, Italy.
mBio (Impact Factor: 6.79). 02/2012; 3(2). DOI: 10.1128/mBio.00010-12
Source: PubMed


The increasing antibiotic resistance of pathogenic Escherichia coli species and the absence of a pan-protective vaccine pose major health concerns. We recently identified, by subtractive reverse vaccinology, nine Escherichia coli antigens that protect mice from sepsis. In this study, we characterized one of them, ECOK1_0290, named FdeC (factor adherence E. coli) for its ability to mediate E. coli adhesion to mammalian cells and extracellular matrix. This adhesive propensity was consistent with the X-ray structure of one of the FdeC domains that shows a striking structural homology to Yersinia pseudotuberculosis invasin and enteropathogenic E. coli intimin. Confocal imaging analysis revealed that expression of FdeC on the bacterial surface is triggered by interaction of E. coli with host cells. This phenotype was also observed in bladder tissue sections derived from mice infected with an extraintestinal strain. Indeed, we observed that FdeC contributes to colonization of the bladder and kidney, with the wild-type strain outcompeting the fdeC mutant in cochallenge experiments. Finally, intranasal mucosal immunization with recombinant FdeC significantly reduced kidney colonization in mice challenged transurethrally with uropathogenic E. coli, supporting a role for FdeC in urinary tract infections.

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Available from: Danilo Gomes Moriel,
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    • "Although, bladder is the common site of UTI in about 95% of cases [7], the infection can cause pyelonephritis , bacteremia, sepsis and sometimes death [3] [7] [8]. Uropathogenic Escherichia coli (UPEC) are isolated from 50% to 90% of all reported cases [9] [10] [11]. Among different virulence factors of UPEC [3] [7] [12], Type 1 pili which has the adhesin FimH is one of the most important UPEC virulence factors [13] [14]. "
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