Bacteriophage against Foodborne Pathogen Shigella dysenteriae
Disciplines
Bacteriology | Food Microbiology | Virology
Abstract (300 words maximum)
Shigella dysenteriae is an important foodborne bacterial pathogen. It causes epidemic dysentery or shigellosis which can be a severe illness with high mortality (up to 20%). Symptoms of shigellosis include diarrhea (often bloody and mucoid), stomach cramps, fever, and hemolytic-uremic syndrome which can be fatal. S. dysenteriae has a low infectious dose. It is easily transmitted through contaminated food and from one person to another. Despite numerous efforts for prevention and control, shigellosis continues to be an important cause of acute diarrhea and dysentery worldwide, particularly in Asia and Africa. The development of an effective control is urgently needed to decrease its global impact. Recently, bacteriophages (phages) have emerged as safe and promising biocontrol agents against bacterial pathogens. Phages are viruses that infect only bacteria. They do not replicate in foods unless their bacterial hosts are present. In addition, phages do not alter food properties and nutritional value. A novel Shigella phage (phage Shig-L) has been isolated. The phage is genus-specific. It is able to infect S. flexneri, S. dysenteriae, and S. sonnei. The objective of this study was to evaluate the effectiveness of the phage infection at 37°C against S. dysenteriae in cucumber juice as a model food system (representing vegetables) at 3 different multiplicity of infections (MOIs).The results from this study showed that regardless of the initial MOI (1, 10, or 100), the phage infection killed off the host cells within 2.5 hr, resulting in more than 5-log (99.999%) reduction in cell concentration, compared to the control. These results clearly demonstrated that the phage infection is highly effective to control S. dysenteriae in the model food system, suggesting that the phage has high potential to be used as a biocontrol agent against Shigella dysenteriae in foods.
Academic department under which the project should be listed
CSM - Molecular and Cellular Biology
Primary Investigator (PI) Name
Jean Lu
Bacteriophage against Foodborne Pathogen Shigella dysenteriae
Shigella dysenteriae is an important foodborne bacterial pathogen. It causes epidemic dysentery or shigellosis which can be a severe illness with high mortality (up to 20%). Symptoms of shigellosis include diarrhea (often bloody and mucoid), stomach cramps, fever, and hemolytic-uremic syndrome which can be fatal. S. dysenteriae has a low infectious dose. It is easily transmitted through contaminated food and from one person to another. Despite numerous efforts for prevention and control, shigellosis continues to be an important cause of acute diarrhea and dysentery worldwide, particularly in Asia and Africa. The development of an effective control is urgently needed to decrease its global impact. Recently, bacteriophages (phages) have emerged as safe and promising biocontrol agents against bacterial pathogens. Phages are viruses that infect only bacteria. They do not replicate in foods unless their bacterial hosts are present. In addition, phages do not alter food properties and nutritional value. A novel Shigella phage (phage Shig-L) has been isolated. The phage is genus-specific. It is able to infect S. flexneri, S. dysenteriae, and S. sonnei. The objective of this study was to evaluate the effectiveness of the phage infection at 37°C against S. dysenteriae in cucumber juice as a model food system (representing vegetables) at 3 different multiplicity of infections (MOIs).The results from this study showed that regardless of the initial MOI (1, 10, or 100), the phage infection killed off the host cells within 2.5 hr, resulting in more than 5-log (99.999%) reduction in cell concentration, compared to the control. These results clearly demonstrated that the phage infection is highly effective to control S. dysenteriae in the model food system, suggesting that the phage has high potential to be used as a biocontrol agent against Shigella dysenteriae in foods.