Scientific breakthroughs advance gut microbiome and Salmonella defense

Researchers are making advancements in understanding and managing gut health through probiotic modification and dietary fiber.

A team led by Professor Krzysztof Grzymajła has developed a method to enhance the protective capabilities of probiotic bacteria against Salmonella. By genetically modifying the Escherichia coli Nissle 1917 strain—specifically using the G66R mutation—scientists increased the bacteria's ability to adhere to intestinal cells. In mouse studies, this modified probiotic significantly reduced Salmonella levels in the spleen and liver compared to standard strains, helping to mitigate the severity of the infection.

Separately, researchers at the Ludwig Institute for Cancer Research in Princeton have investigated how dietary fiber influences bacterial metabolism. Their findings, published in PNAS and Nature Metabolism, indicate that fiber and certain plant proteins prevent bacteria from consuming host proteins, such as those in the intestinal mucosa. When bacteria consume host proteins, they produce harmful phenols; however, fiber promotes the production of beneficial compounds. The researchers identified indigestible plant proteins, termed ‘Prif’ (protein-imitating fiber), which provide the necessary material for bacteria to produce beneficial phenols instead of harmful metabolites.