<abstract xmlns="http://www.w3.org/1999/xhtml">

<p>Shiga toxin-producing <italic>Escherichia coli</italic> (STEC) strains also called verotoxin-producing <italic>E. coli</italic> (VTEC) represent one of the most important groups of food-borne pathogens that can cause several human diseases such as hemorrhagic colitis (HC) and hemolytic – uremic syndrome (HUS) worldwide. The ability of STEC strains to cause disease is associated with the presence of wide range of identified and putative virulence factors including those encoding Shiga toxin. In this study, we examined the distribution of various virulence determinants among STEC strains isolated in Poland from different sources. A total of 71 Shiga toxin-producing <italic>E. coli</italic> strains isolated from human, cattle and food over the years 1996–2010 were characterized by microarray and PCR detection of virulence genes. As <italic>stx1a</italic> subtype was present in all of the tested Shiga toxin 1 producing <italic>E. coli</italic> strains, a greater diversity of subtypes was found in the gene <italic>stx2</italic>, which occurred in five subtypes: <italic>stx2a, stx2b, stx2c, stx2d, stx2g</italic>. Among STEC O157 strains we observed conserved core set of 14 virulence factors, stable in bacteria genome at long intervals of time. There was one cattle STEC isolate which possessed verotoxin gene as well as <italic>sta1</italic> gene encoded heat-stable enterotoxin STIa characteristic for enterotoxigenic <italic>E. coli.</italic> To the best of our knowledge, this is the first comprehensive analysis of virulence gene profiles identified in STEC strains isolated from human, cattle and food in Poland. The results obtained using microarrays technology confirmed high effectiveness of this method in determining STEC virulotypes which provides data suitable for molecular risk assessment of the potential virulence of this bacteria.</p>
</abstract>

Shiga toxin-producing Escherichia coli (STEC) strains also called verotoxin-producing E. coli (VTEC) represent one of the most important groups of food-borne pathogens that can cause several human diseases such as hemorrhagic colitis (HC) and hemolytic – uremic syndrome (HUS) worldwide. The ability of STEC strains to cause disease is associated with the presence of wide range of identified and putative virulence factors including those encoding Shiga toxin. In this study, we examined the distribution of various virulence determinants among STEC strains isolated in Poland from different sources. A total of 71 Shiga toxin-producing E. coli strains isolated from human, cattle and food over the years 1996–2010 were characterized by microarray and PCR detection of virulence genes. As stx1a subtype was present in all of the tested Shiga toxin 1 producing E. coli strains, a greater diversity of subtypes was found in the gene stx2, which occurred in five subtypes: stx2a, stx2b, stx2c, stx2d, stx2g. Among STEC O157 strains we observed conserved core set of 14 virulence factors, stable in bacteria genome at long intervals of time. There was one cattle STEC isolate which possessed verotoxin gene as well as sta1 gene encoded heat-stable enterotoxin STIa characteristic for enterotoxigenic E. coli. To the best of our knowledge, this is the first comprehensive analysis of virulence gene profiles identified in STEC strains isolated from human, cattle and food in Poland. The results obtained using microarrays technology confirmed high effectiveness of this method in determining STEC virulotypes which provides data suitable for molecular risk assessment of the potential virulence of this bacteria.

Molecular Characterization of Shiga Toxin-Producing <italic>Escherichia coli</italic> Strains Isolated in Poland

Polish Journal of Microbiology

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Molecular Characterization of Shiga Toxin-Producing  Strains Isolated in Poland

Shiga toxin-producing Escherichia coli (STEC) strains also called verotoxin-producing E. coli (VTEC) represent one of the most important groups of food-borne...

Molecular Characterization of Shiga Toxin-Producing Escherichia coli Strains Isolated in Poland

Published Online: Aug 26, 2016

Page range: 261 - 269

Received: Dec 03, 2014

Accepted: Feb 11, 2016

DOI: https://doi.org/10.5604/17331331.1215601

Keywords
microarray detection, Shiga toxin-producing, virulence gene

© 2016 ALEKSANDRA JANUSZKIEWICZ et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Molecular Characterization of Shiga Toxin-Producing Escherichia coli Strains Isolated in Poland

Published Online: Aug 26, 2016

Page range: 261 - 269

Received: Dec 03, 2014

Accepted: Feb 11, 2016

DOI: https://doi.org/10.5604/17331331.1215601

Keywordsmicroarray detection, Shiga toxin-producing, virulence gene

© 2016 ALEKSANDRA JANUSZKIEWICZ et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Keywords
microarray detection, Shiga toxin-producing, virulence gene