Modern large‐scale agricultural practices that incorporate high density farming with subtherapeutic antibiotic dosing are considered a major contributor to the rise of antibiotic‐resistant bacterial infections of humans with species of
To determine if the bacteriophage abortive infection system ToxIN is present in foodborne Salmonella and if it protects against infection by bacteriophages specific to enteric bacteria.
A set of foodborne Salmonella enteritidis isolates from a 2010 eggshell outbreak was identified via BLASTN (basic local alignment search tool nucleotide) queries as harboring a close homolog of ToxIN, carried on a plasmid with putative mobilization proteins. This homolog was cloned into a plasmid vector and transformed into the laboratory strain Salmonella typhimurium LT2 and tested against a set of Salmonella-specific phages (FelixO1, S16, Sp6, LPST153, and P22 HT105/1 int-201). ToxIN reduced infection by FelixO1, S16, and LPST153 by ∼1–4 log PFU ml−1 while reducing the plaque size of Sp6. When present in LT2 and Escherichia coli MG1655, ToxIN conferred cross-genus protection against phage isolates, which infect both bacteria. Finally, the putative ToxIN plasmid was found in whole-genome sequence contigs of several Salmonella serovars, pathogenic E. coli, and other pathogenic enterobacteria.
Salmonella and E. coli can resist infection by several phages via ToxIN under laboratory conditions; ToxIN is present in foodborne pathogens including Salmonella and Shiga-toxigenic E. coli.
- NSF-PAR ID:
- 10479743
- Publisher / Repository:
- Oxford University Press
- Date Published:
- Journal Name:
- Journal of Applied Microbiology
- Volume:
- 134
- Issue:
- 12
- ISSN:
- 1365-2672
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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