Killing Salmonella using human feces

Posted May 5, 2013 by Tim Sandle
Researchers have recently found a novel mode of interaction between Salmonella, a foodborne pathogen, and the gut bacteria, where certain bacteria isolated from human feces can kill the pathogen.
UofR Medical Center
Scientists have isolated certain gut bacteria that can lead to the inactivation of the food-poisoning Salmonella bacterium. For this to happen, cell-to-cell contact is required between the 'good bacteria', isolated from human feces, and the 'bad bacterium' Salmonella.
Salmonella bacteria cause illnesses such as typhoid fever, paratyphoid fever, and foodborne illness. With food, Salmonellosis is a disease caused by raw or undercooked food. Infection usually occurs when a person ingests foods that contain a high concentration of the bacteria, similar to a culture medium.
For the study, researchers collected fecal samples from several healthy human donors and used the a laboratory to culture faecal bacteria together with Salmonella under conditions that mimicked those in the human colon.
What the scientists found was that the gut bacteria effectively inactivated Salmonella in mixed cultures, but only when cell contact between both populations was possible. Salmonella inactivation was not observed when a membrane was included into the system to prevent cell contact between the different bacterial populations.
Further research is required, but the findings could lead to the isolation of certain bacteria which could be used to counter the food poisoning organism. The findings have been published in the journal Applied and Environmental Microbiology in an article titled "Loss of culturability of Salmonella Typhimurium upon cell-cell contact with human faecal bacteria."