Original Research ARTICLE
Phage predation shapes the population structure of Shiga-toxigenic Escherichia coli O157:H7 in the UK: an evolutionary perspective
- 1University of Bath, United Kingdom
- 2Public Health England, United Kingdom
Natural genetic diversity in bacteria reflects interactions with the host environment, the resident microbiome and selection through predatory lytic bacteriophages. In studies of human and animal gut bacteria, it is important to consider the role of these phages in the host-pathogen milieu. We use an important zoonotic pathogen Shiga toxigenic Escherichia coli (STEC) O157:H7 to investigate this. Our study provides evidence that phage resistance profiles are well maintained at the sub lineage level with variation in profiles within sub lineages being uncommon. This indicates that phage resistance heterogeneity happened early on in the STEC O157:H7 natural history and that occasional “wobbles” don’t often outcompete the stable lineage unless combined with a competitive advantage. We discuss an example of this in the acquisition of stx2a that, while an important virulence factor, also conveys increased phage cross-resistance. We also discuss the role of phage resistance in co-occurrence of the three stable lineages worldwide and whether differing phage resistance is maintaining diversity and shaping the host-associated bacterial population.
Keywords: Phage, Escherichia coli O157:H7, population structure, host, evolution
Received: 13 Mar 2019;
Accepted: 18 Jul 2019.
Edited by:Jesse Shapiro, Université de Montréal, Canada
Reviewed by:Dominique Belin, Université de Genève, Switzerland
Mark Eppinger, University of Texas at San Antonio, United States
Copyright: © 2019 Cowley, Dallman, Jenkins and Sheppard. 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) and the copyright owner(s) 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: Dr. Lauren A. Cowley, University of Bath, Bath, BA2 7AY, South West England, United Kingdom, firstname.lastname@example.org