Characteristics of Shigatoxin-Producing Strains Isolated during 2010-2014 from Human Infections in Switzerland.

The aim of this study was to characterize a collection of 95 Shigatoxin-producing .coli (STEC) isolated from human patients in Switzerland during 2010-2014. We performed O and H serotyping and molecular subtyping.

Subtilase contributes to the cytotoxicity of a Shiga toxin-producing Escherichia coli strain encoding three different toxins.

Food-borne Shiga toxin-producing Escherichia coli (STEC) O113:H21 strain TS18/08, that has previously been isolated from mixed minced meat, harbors the Shiga toxin (Stx) encoding allele stx2a, the plasmid-located subtilase cytotoxin encoding allele subAB1 and the cytolethal distending toxin type V encoding gene cdt-V. In the current study, it could be shown that each of these toxin genes was transcribed with different transcription levels at different time points by RT real time PCR under laboratory batch conditions in LB-broth. The transcription maximum for cdt-V and subAB1 was observed after 3h while stx2a transcription was highest after 6h of incubation.

Molecular analysis of subtilase cytotoxin genes of food-borne Shiga toxin-producing Escherichia coli reveals a new allelic subAB variant.

Background: The open reading frames of subAB genes and their flanking regions of 18 food-borne Shiga toxin-producing E. coli (STEC) strains were analyzed.

Results: All but one subAB open reading frames (ORF) were complete in all STEC strains.

Phylogenetic and molecular analysis of food-borne shiga toxin-producing Escherichia coli.

Seventy-five food-associated Shiga toxin-producing Escherichia coli (STEC) strains were analyzed by molecular and phylogenetic methods to describe their pathogenic potential. The presence of the locus of proteolysis activity (LPA), the chromosomal pathogenicity island (PAI) PAI ICL3, and the autotransporter-encoding gene sabA was examined by PCR. Furthermore, the occupation of the chromosomal integration sites of the locus of enterocyte effacement (LEE), selC, pheU, and pheV, as well as the Stx phage integration sites yehV, yecE, wrbA, z2577, and ssrA, was analyzed.

Genetic types, gene repertoire, and evolution of isolates of the Salmonella enterica serovar 4,5,12:i:- Spanish clone assigned to different phage types.

Salmonella enterica subsp. enterica 4,[5],12:i:- is one of the most prevalent serovars associated with human infections worldwide. Two multidrug-resistant clones, designated Spanish and European clones, are recognized as having importance for public health and are subject to control measures in the European Union.

Clonal dissemination of Salmonella enterica serovar Infantis in Germany.

Salmonella enterica serovar Infantis (Salmonella Infantis) is consistently isolated from broiler chickens, pigs, and humans worldwide. This study investigated 93 epidemiologically unrelated Salmonella Infantis strains isolated in Germany between 2005 and 2008 in respect to their transmission along the food chain. Various phenotypic and genotypic methods were applied, and the pathogenicity and resistance gene repertoire was determined.

Diversity of Salmonella enterica serovar Derby isolated from pig, pork and humans in Germany.

Salmonella enterica serovar Derby (S. Derby) is one of the most prevalent serovars in pigs in Europe and in the U.S.

Antimicrobial resistance and virulence determinants in European Salmonella genomic island 1-positive Salmonella enterica isolates from different origins.

Salmonella genomic island 1 (SGI1) contains a multidrug resistance region conferring the ampicillin-chloramphenicol-streptomycin-sulfamethoxazole-tetracycline resistance phenotype encoded by bla(PSE-1), floR, aadA2, sul1, and tet(G). Its increasing spread via interbacterial transfer and the emergence of new variants are important public health concerns. We investigated the molecular properties of SGI1-carrying Salmonella enterica serovars selected from a European strain collection.

Pork contaminated with Salmonella enterica serovar 4,[5],12:i:-, an emerging health risk for humans.

Salmonella enterica subsp. enterica serovar 4,[5],12:i:- is a monophasic variant of S. enterica serovar Typhimurium (antigenic formula 4,[5],12:i:1,2).

Virulotyping and antimicrobial resistance typing of Salmonella enterica serovars relevant to human health in Europe.

The combination of virulence gene and antimicrobial resistance gene typing using DNA arrays is a recently developed genomics-based approach to bacterial molecular epidemiology. We have now applied this technology to 523 Salmonella enterica subsp. enterica strains collected from various host sources and public health and veterinary institutes across nine European countries.

[Characterisation of a phenotypic monophasic variant belonging to Salmonella enterica subsp. enterica serovar Typhimurium from wild birds and its possible transmission to cats and humans].

In the last two years The National Salmonella Reference Laboratory (NRL-Salm) received an accumulating number of salmonellae with sero-formula 4,12:-:1,2 isolated from perished wild birds, particularly siskins. Within these strains flagellar antigen of the first phase was phenotypically not detectable. By PCR a fragment could be amplified coding specifically for the H:i-flagellar antigen.

The universal stress protein UspC scaffolds the KdpD/KdpE signaling cascade of Escherichia coli under salt stress.

The sensor kinase KdpD and the response regulator KdpE control induction of the kdpFABC operon encoding the high-affinity K(+)-transport system KdpFABC in response to K(+) limitation or salt stress. Under K(+) limiting conditions the Kdp system restores the intracellular K(+) concentration, while in response to salt stress K(+) is accumulated far above the normal content. The kinase activity of KdpD is inhibited at high concentrations of K(+), so it has been puzzling how the sensor can be activated in response to salt stress.