Original Research ARTICLE
Shiga toxin-converting phages and the emergence of new pathogenic Escherichia coli: a world in motion
- European Reference Laboratory for Escherichia coli, Dipartimento di Sanità Pubblica Veterinaria e Sicurezza Alimentare, Istituto Superiore di Sanità, Rome, Italy
Shiga toxin (Stx)-producing Escherichia coli (STEC) are pathogenic E. coli causing diarrhea, hemorrhagic colitis (HC) and hemolytic uremic syndrome (HUS). STEC are characterized by a constellation of virulence factors additional to Stx and have long been regarded as capable to cause HC and HUS when possessing the ability of inducing the attaching and effacing (A/E) lesion to the enterocyte, although strains isolated from such severe infections sometimes lack this virulence feature. Interestingly, the capability to cause the A/E lesion is shared with another E. coli pathogroup, the Enteropathogenic E. coli (EPEC). In the very recent times, a different type of STEC broke the scene causing a shift in the paradigm for HUS-associated STEC. In 2011, a STEC O104:H4 caused a large outbreak with more than 800 HUS and 50 deaths. Such a strain presented the adhesion determinants of Enteroaggregative E. coli (EAggEC). We investigated the possibility that, besides STEC and EAggEC, other pathogenic E. coli could be susceptible to infection with stx-phages. A panel of stx2-phages obtained from STEC isolated from human disease was used to infect experimentally E. coli strains representing all the known pathogenic types, including both diarrheagenic E. coli (DEC) and extra-intestinal pathogenic E. coli (ExPEC). We observed that all the E. coli pathogroups used in the infection experiments were susceptible to the infection. Our results suggest that the stx2-phages used may not have specificity for E. coli adapted to the intestinal environment, at least in the conditions used. Additionally, we could only observe transient lysogens suggesting that the event of stable stx2-phage acquisition occurs rarely.
Keywords: Escherichia coli, Shigatoxin, stx-phages, STEC, pathogroups
Citation: Tozzoli R, Grande L, Michelacci V, Ranieri P, Maugliani A, Caprioli A and Morabito S (2014) Shiga toxin-converting phages and the emergence of new pathogenic Escherichia coli: a world in motion. Front. Cell. Infect. Microbiol. 4:80. doi: 10.3389/fcimb.2014.00080
Received: 24 April 2014; Accepted: 01 June 2014;
Published online: 20 June 2014.
Edited by:Eelco Franz, Centre for Infectious Disease Control, Netherlands
Reviewed by:Maite Muniesa, University of Barcelona, Spain
Lothar Beutin, Federal Institute for Risk Assessment, Germany
Copyright © 2014 Tozzoli, Grande, Michelacci, Ranieri, Maugliani, Caprioli and Morabito. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
*Correspondence: Stefano Morabito, European Reference Laboratory for Escherichia coli, Dipartimento di Sanità Pubblica Veterinaria e Sicurezza Alimentare, Istituto Superiore di Sanità, Viale Regina Elena 299, Rome 00161, Italy e-mail: email@example.com