Bacterial Eaters Kill Salmonella and Shigella
Disciplines
Bacteriology | Food Microbiology | Virology
Abstract (300 words maximum)
Salmonella and Shigella are well-known bacterial pathogens that frequently cause foodborne diseases. It was estimated that each year Salmonella cause 93.8 million cases of gastroenteritis and 155,000 deaths globally. Shigella causes 164.7 million cases and 1.1 million deaths throughout the world yearly. It is urgent to effectively control of these pathogens in food systems. Bacteriophages (phages) are “bacterial eaters” that kill bacteria. Phages have emerged as promising biocontrol agents against bacterial pathogens because 1) they can cause rapid bacterial death, 2) they do not replicate in foods unless their bacterial hosts are present, 3) they do not infect humans and other animals, and 4) they do not alter food color, odor, taste, and nutritional value. This project partially characterized two phages (ΦEnt and ΦShig-Tf) infecting Salmonella and Shigella, respectively. Specifically, we measured the host ranges and 1- step growth curves of the 2 phages and evaluated the thermal stabilities of ΦEnt and its host in Tryptic Soy Broth. ΦEnt showed very broad host range infecting 11 Salmonella strains and 3 Shigella stains tested. ΦShig-Tf is able to infect 2 Shigella strains, Escherichia coli O157:H7, and Enterobacter cloacae. The burst sizes of the two phages are about 100 phage particles per infected cell. ΦEnt and its Salmonella host were stable at 50°C for at least 4 min. However, ΦEnt was less sensitive to 63°C and 72°C than its host at the same temperatures. This project provided important information for evaluating the potential of the two phages as biocontrol agents in food system.
Academic department under which the project should be listed
CSM - Molecular and Cellular Biology
Primary Investigator (PI) Name
Jean Lu
Bacterial Eaters Kill Salmonella and Shigella
Salmonella and Shigella are well-known bacterial pathogens that frequently cause foodborne diseases. It was estimated that each year Salmonella cause 93.8 million cases of gastroenteritis and 155,000 deaths globally. Shigella causes 164.7 million cases and 1.1 million deaths throughout the world yearly. It is urgent to effectively control of these pathogens in food systems. Bacteriophages (phages) are “bacterial eaters” that kill bacteria. Phages have emerged as promising biocontrol agents against bacterial pathogens because 1) they can cause rapid bacterial death, 2) they do not replicate in foods unless their bacterial hosts are present, 3) they do not infect humans and other animals, and 4) they do not alter food color, odor, taste, and nutritional value. This project partially characterized two phages (ΦEnt and ΦShig-Tf) infecting Salmonella and Shigella, respectively. Specifically, we measured the host ranges and 1- step growth curves of the 2 phages and evaluated the thermal stabilities of ΦEnt and its host in Tryptic Soy Broth. ΦEnt showed very broad host range infecting 11 Salmonella strains and 3 Shigella stains tested. ΦShig-Tf is able to infect 2 Shigella strains, Escherichia coli O157:H7, and Enterobacter cloacae. The burst sizes of the two phages are about 100 phage particles per infected cell. ΦEnt and its Salmonella host were stable at 50°C for at least 4 min. However, ΦEnt was less sensitive to 63°C and 72°C than its host at the same temperatures. This project provided important information for evaluating the potential of the two phages as biocontrol agents in food system.