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Characterization of Campylobacter phages including analysis of host range by selected Campylobacter Penner serotypes.

Hansen VM, Rosenquist H, Baggesen DL, Brown S, Christensen BB - BMC Microbiol. (2007)

Bottom Line: Campylobacter specific bacteriophages (phages) have been proposed as an alternative agent for reducing the burden of Campylobacter in broilers.To identify the potential of phages as a Campylobacter reducing agent we needed to determine their infectivity on a panel of isolates representing the Campylobacter strains found in broilers as well as humans.This study provides the basis for future experiments in Campylobacter phages and knowledge for the selection of Campylobacter phages for biocontrol in broilers.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Microbiology and Risk Assesment, National Food Institute, Soeborg, Denmark. vmh@arbejdsmiljoforskning.dk

ABSTRACT

Background: The predominant food borne pathogen in the western world today is Campylobacter. Campylobacter specific bacteriophages (phages) have been proposed as an alternative agent for reducing the burden of Campylobacter in broilers. One concern in relation to phage biocontrol is the narrow host range often displayed by phages. To identify the potential of phages as a Campylobacter reducing agent we needed to determine their infectivity on a panel of isolates representing the Campylobacter strains found in broilers as well as humans.

Results: In this study, Campylobacter phages were isolated from the intestines of broilers and ducks and from abattoir sewage. Twelve phages were investigated to determine their ability to infect the Campylobacter Penner serotypes commonly present in Danish poultry and patients with campylobacteriosis. A total of 89% of the Campylobacter jejuni strains and 14% of the Campylobacter coli strains could be infected by at least one of the bacteriophages. The majority of the phages infected the most common serotypes in Danish broilers (O:1,44; O:2; O:4-complex), but showed limited ability to infect 21 of the less frequent Campylobacter serotypes. Pulse field gel electrophoresis (PFGE) and restriction endonuclease analysis (REA) were used to characterize the phage genomes. Three categories of bacteriophages were observed. I: a genome size of approximately 194 kb and refractory to digestion with HhaI; II: a genome size of approximately 140 kb and digestible by HhaI; and III: a genome size undeterminable in PFGE. The categorization of the phages correlated with the host range patterns displayed by the phages. Six phages were subjected to transmission electron microscopy (TEM). They all belonged to the family of Myoviridae.

Conclusion: We have characterized and identified the host range of 12 Danish Campylobacter phages. Due to their ability to infect the majority of the common serotypes in Denmark we suggest the phages can become an effective agent in the effort to reduce the incidence of campylobacteriosis in Denmark. This study provides the basis for future experiments in Campylobacter phages and knowledge for the selection of Campylobacter phages for biocontrol in broilers.

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HhaI treated genomes of phages representing the 7 REA group. The DNA bands of phages treated with HhaI are displayed in lane 2–8. The genome of F14 does not display any DNA bands in lane 2 whereas the genome of F325 display a single band of DNA in lane 3 due to it being refractory to HhaI degestion. The next 5 lanes represent from the left to the right the HhaI restriction patterns of the 140 Kb phages (group II a-e). Concatemer (New England Biolabs, #N0350S) is seen in the first lane.
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Figure 1: HhaI treated genomes of phages representing the 7 REA group. The DNA bands of phages treated with HhaI are displayed in lane 2–8. The genome of F14 does not display any DNA bands in lane 2 whereas the genome of F325 display a single band of DNA in lane 3 due to it being refractory to HhaI degestion. The next 5 lanes represent from the left to the right the HhaI restriction patterns of the 140 Kb phages (group II a-e). Concatemer (New England Biolabs, #N0350S) is seen in the first lane.

Mentions: The phages were analyzed by PFGE and REA to determine genome size and sensitivity towards digestion with the restriction enzyme HhaI. Eventhough a signal were visible in the F14 well no DNA were observed to enter the the pulsed field gel, which precluded estimation of the genome size. A prolonged running time of 12 h did not change the observed outcome for phage F14. Phage F325 displayed the largest genome (~194 kb) and the remaining phages had each an estimated genome size of approximately 140 kb (Table 2). REA showed that the DNA isolated from phage F325 could not be digested with HhaI. An attempt to digest the expected F14 DNA with HhaI was unsuccesful, since DNA bands still were absent in the gel (Figure 1). All phages with a genome size of ~140 kb could be digested with HhaI. Each phage displayed between 2–5 strong bands in the PFGE ranging in size between 9–50 kb (Figure 1). The REA allowed for categorizing the 140 kb phages into five different restriction patterns (a-e) (Table 2).


Characterization of Campylobacter phages including analysis of host range by selected Campylobacter Penner serotypes.

Hansen VM, Rosenquist H, Baggesen DL, Brown S, Christensen BB - BMC Microbiol. (2007)

HhaI treated genomes of phages representing the 7 REA group. The DNA bands of phages treated with HhaI are displayed in lane 2–8. The genome of F14 does not display any DNA bands in lane 2 whereas the genome of F325 display a single band of DNA in lane 3 due to it being refractory to HhaI degestion. The next 5 lanes represent from the left to the right the HhaI restriction patterns of the 140 Kb phages (group II a-e). Concatemer (New England Biolabs, #N0350S) is seen in the first lane.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2194700&req=5

Figure 1: HhaI treated genomes of phages representing the 7 REA group. The DNA bands of phages treated with HhaI are displayed in lane 2–8. The genome of F14 does not display any DNA bands in lane 2 whereas the genome of F325 display a single band of DNA in lane 3 due to it being refractory to HhaI degestion. The next 5 lanes represent from the left to the right the HhaI restriction patterns of the 140 Kb phages (group II a-e). Concatemer (New England Biolabs, #N0350S) is seen in the first lane.
Mentions: The phages were analyzed by PFGE and REA to determine genome size and sensitivity towards digestion with the restriction enzyme HhaI. Eventhough a signal were visible in the F14 well no DNA were observed to enter the the pulsed field gel, which precluded estimation of the genome size. A prolonged running time of 12 h did not change the observed outcome for phage F14. Phage F325 displayed the largest genome (~194 kb) and the remaining phages had each an estimated genome size of approximately 140 kb (Table 2). REA showed that the DNA isolated from phage F325 could not be digested with HhaI. An attempt to digest the expected F14 DNA with HhaI was unsuccesful, since DNA bands still were absent in the gel (Figure 1). All phages with a genome size of ~140 kb could be digested with HhaI. Each phage displayed between 2–5 strong bands in the PFGE ranging in size between 9–50 kb (Figure 1). The REA allowed for categorizing the 140 kb phages into five different restriction patterns (a-e) (Table 2).

Bottom Line: Campylobacter specific bacteriophages (phages) have been proposed as an alternative agent for reducing the burden of Campylobacter in broilers.To identify the potential of phages as a Campylobacter reducing agent we needed to determine their infectivity on a panel of isolates representing the Campylobacter strains found in broilers as well as humans.This study provides the basis for future experiments in Campylobacter phages and knowledge for the selection of Campylobacter phages for biocontrol in broilers.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Microbiology and Risk Assesment, National Food Institute, Soeborg, Denmark. vmh@arbejdsmiljoforskning.dk

ABSTRACT

Background: The predominant food borne pathogen in the western world today is Campylobacter. Campylobacter specific bacteriophages (phages) have been proposed as an alternative agent for reducing the burden of Campylobacter in broilers. One concern in relation to phage biocontrol is the narrow host range often displayed by phages. To identify the potential of phages as a Campylobacter reducing agent we needed to determine their infectivity on a panel of isolates representing the Campylobacter strains found in broilers as well as humans.

Results: In this study, Campylobacter phages were isolated from the intestines of broilers and ducks and from abattoir sewage. Twelve phages were investigated to determine their ability to infect the Campylobacter Penner serotypes commonly present in Danish poultry and patients with campylobacteriosis. A total of 89% of the Campylobacter jejuni strains and 14% of the Campylobacter coli strains could be infected by at least one of the bacteriophages. The majority of the phages infected the most common serotypes in Danish broilers (O:1,44; O:2; O:4-complex), but showed limited ability to infect 21 of the less frequent Campylobacter serotypes. Pulse field gel electrophoresis (PFGE) and restriction endonuclease analysis (REA) were used to characterize the phage genomes. Three categories of bacteriophages were observed. I: a genome size of approximately 194 kb and refractory to digestion with HhaI; II: a genome size of approximately 140 kb and digestible by HhaI; and III: a genome size undeterminable in PFGE. The categorization of the phages correlated with the host range patterns displayed by the phages. Six phages were subjected to transmission electron microscopy (TEM). They all belonged to the family of Myoviridae.

Conclusion: We have characterized and identified the host range of 12 Danish Campylobacter phages. Due to their ability to infect the majority of the common serotypes in Denmark we suggest the phages can become an effective agent in the effort to reduce the incidence of campylobacteriosis in Denmark. This study provides the basis for future experiments in Campylobacter phages and knowledge for the selection of Campylobacter phages for biocontrol in broilers.

Show MeSH
Related in: MedlinePlus