Escherichia coli alpha-hemolysin (HlyA), archetype of a bacterial pore-forming toxin, has been reported to deregulate physiological Ca2+ channels, thus inducing periodic low-frequency Ca2+ oscillations that trigger transcriptional processes in mammalian cells. The present study was undertaken to delineate the mechanisms underlying the Ca2+ oscillations. Patch-clamp experiments were combined wit...

Background: Urinary tract infections are one of the most frequent health problems and Uropathogenic Escherichia coli is the major pathogen resulting UTIs. The severity of UTIs is caused by the expression of a large range of virulence factors.In this study, we evaluated the allelic frequency fimH gene, in UPECs isolated from patients with UTIs. This study also aimed to determine the roles of C64...

introduction : the innate immune system as the first line of defense against the pathogens recognizes pathogen-associated molecular patterns (pamps) by toll-like receptors (tlrs). interaction of bacterial pamps by tlrs results in activation of innate and acquired immunity. fimh adhesin, a minor component of type 1 fimbriae encoded by uropathogenic escherichia coli (upec) is a pamp of tlr4 that ...

The pore-forming hemolysin (HlyA) of Escherichia coli represents a unique class of bacterial toxins that require a posttranslational modification for activity. The inactive protoxin pro-HlyA is activated intracellularly by amide linkage of fatty acids to two internal lysine residues 126 amino acids apart, directed by the cosynthesized HlyC protein with acyl carrier protein as the fatty acid don...

In uropathogenic Escherichia coli, mannose-specific adhesion is mediated by the FimH adhesin located at the tip of type 1 fimbriae. Novel mannosylated N-aryl substituted 3-hydroxypyridin-4ones with meta substituents on the aryl part of the molecule were prepared, and their inhibitory properties towards the adhesion of E. coli to guinea pig erythrocytes explored using the hemagglutination assay....

Urinary tract infections (UTIs) are associated with high rates of morbidity and mortality worldwide, and uropathogenic Escherichia coli (UPEC) is the main etiologic agent. Fimbriae assembled on the bacterial surface are essential for adhesion to the urinary tract epithelium. In this study, the FimH, CsgA, and PapG adhesins were fused to generate biomolecules for use as potential target vaccines...

The first step in the colonization of the human urinary tract by pathogenic Escherichia coli is the mannose-sensitive binding of FimH, the adhesin present at the tip of type 1 pili, to the bladder epithelium. We elucidated crystallographically the interactions of FimH with D-mannose. The unique site binding pocket occupied by D-mannose was probed using site-directed mutagenesis. All but one of ...

Using the combination method with PCR phylogrouping and fimH SNPs analysis, this study investigates the epidemiology of Extra-intestinal pathogenic E. coli in China. 116 E. coli strains including (74 from Urine, 39 from other extra-intestinal sources and 3 references strains) were collected. The bacteria Genomic DNA were extracted; phylogroup and the fimH gene amplifications were determined by ...

While the lifetime of conventional receptor-ligand interactions is shortened by tensile mechanical force, some recently discovered interactions, termed catch bonds, can be strengthened by force. Motivated by the search for the underpinning structural mechanisms, we here explore the structural dynamics of the binding site of the bacterial adhesive protein FimH by molecular dynamics and steered m...

Salmonella enterica serovar Typhimurium can be internalized by immature dendritic cells (DCs). The interacting host and bacterial molecules initiating this process remain uncharacterized. The objective of this study was to investigate whether specific fimbriae are involved in the early step of binding and uptake of Salmonella by DCs. Type 1 fimbriated S. enterica serovar Typhimurium or recombin...