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ARS Home » Southeast Area » Fayetteville, Arkansas » Poultry Production and Product Safety Research » Research » Publications at this Location » Publication #216376
Title: Salmonella host range of bacteriophages which infect multiple genra

Author
item BIELKE, L
item HIGGINS, S
item Donoghue, Ann - Annie
item TELLEZ, G
item DONOGHUE, D
item HARGIS, B

Submitted to: Poultry Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/22/2007
Publication Date: N/A
Citation: N/A

Interpretive Summary: Conventionally, bacteriophages are presented as viruses capable of amplification only in a narrow range of closely related bacteria. We selected bacteriophages with the ability to infect more than one bacterial genus. Initially, wild-type bacteriophages were selected for ability to form plaques in Salmonella enteritidis (SE) agar overlays. For determination of host specificity, a pool of 44 bacteriophage isolates were evaluated for ability to propagate in individual enteric bacterial isolates previously identified as non-pathogenic. These experiments suggest that bacteriophage host range is not always genera-restricted, and that selection of subpopulations of bacteriophages capable of amplification in alternative genera may provide a tool for selection of broad host-range bacteriophages for the pathogen of interest. Selection of non-pathogenic host isolates to support replication of Salmonella bacteriophages may allow improved safety for bacteriophage application to poultry as this would reduce the necessity for 100% purification of the bacteriophage(s) from resistant host bacteria.

Technical Abstract: Conventionally, bacteriophages are presented as viruses capable of amplification only in a narrow range of closely related bacteria. We selected bacteriophages with the ability to infect more than one bacterial genus. Initially, wild-type bacteriophages were selected for ability to form plaques in Salmonella enteritidis (SE) agar overlays. For determination of host specificity, a pool of 44 bacteriophage isolates were evaluated for ability to propagate in individual enteric bacterial isolates previously identified as non-pathogenic. In two separate experiments, bacteriophages were combined with each bacterial isolate in tryptic soy broth. This mixture was incubated, with fresh bacterial culture and media for 4 sequential passes, and the resulting bacteriophage titer was determined using SE. One Klebsiella and 3 different Escherichia isolates successfully amplified some bacteriophage(s) from the SE-selected bacteriophage pool. Amplification in each species was confirmed by the formation of increased PFU’s in a TSA overlay with the enteric (alternative host) bacteria. In a subsequent study, 2 selected wide-host-range bacteriophages were evaluated for ability to amplify in 10 different Salmonella isolates (different serovars) by amplification in broth culture. Bacteriophage A had the ability to amplify in 6 different Salmonella serovars and bacteriophage B had the ability to amplify in 2 different Salmonella serovars. These experiments suggest that bacteriophage host range is not always genera-restricted, and that selection of subpopulations of bacteriophages capable of amplification in alternative genera may provide a tool for selection of broad host-range bacteriophages for the pathogen of interest. Selection of non-pathogenic host isolates to support replication of Salmonella bacteriophages may allow improved safety for bacteriophage application to poultry as this would reduce the necessity for 100% purification of the bacteriophage(s) from resistant host bacteria.