Researchers from the University of Leipzig discovered a receptor in humans and great apes that detect metabolites from bacteria commonly found in fermented foods that also stimulates the movement of immune cells. Their research findings were published in the journal PLOS Genetics.

Scientists know that there are many health benefits when it comes to people consuming lactic acid bacteria. However, their knowledge on the reason why bacteria, when ingested is helpful and on how this affects the immune system. Lead author Claudia Staubert and her co-researchers were able to determine how lactic acid bacteria interact with the human body. The researchers were first working on proteins on the surface of the cells called hydroxycarboxylic acid (HCA) receptors. There are only two kinds of HCA receptors in most animals except for humans and great apes that have three. Lactic acid bacteria produce a metabolite D-phenyllactic acid that strongly attaches to the third HCA receptor allowing the immune system to know their presence.

"The researchers propose that the third HCA receptor arose in a common ancestor of humans and great apes, and enabled them to consume foods that are starting to decay, such as fruits picked up from the ground," according to Eureka Alert.

The results of the study show the relationship between microbes and their human hosts and widening new knowledge regarding the multiple positive effects of consuming fermented foods.

"We are convinced that this receptor very likely mediates some beneficial and anti-inflammatory effects of lactic acid bacteria in humans," stated author Claudia Stäubert. "That is why we believe it could serve as a potential drug target to treat inflammatory diseases."