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Abstract AimsTo 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. Methods and resultsA 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. ConclusionsSalmonella 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.
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The toxin from a ParDE toxin-antitoxin system found in Pseudomonas aeruginosa offers protection to cells challenged with anti-gyrase antibiotics: PaParE toxin partially protects cells from antibiotic toxicity
- Award ID(s):
- 1911370
- PAR ID:
- 10145884
- Date Published:
- Journal Name:
- Molecular Microbiology
- Volume:
- 111
- Issue:
- 2
- ISSN:
- 0950-382X
- Page Range / eLocation ID:
- 441 to 454
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1111/mmi.14165
