New study demonstrates interactions between the microbiota and pathogenic bacteria in the gut

A recently (7 July) in Nature published study demonstrates: The microbiome plays an important role in human health. Changes in the microbiota can confer resistance to or promote infection by pathogenic bacteria. With Prof. Andreas Bäumler from the Department of Medical Microbiology and Immunology, from the University of California spoke Carola Timmel.

Prof. Bäumler, the fact, that the microbiom plays an important role in combating pathogenic bacteria, is known for quite some time. Which new findings could be obtained by the survey?

The field is entering a phase in which the mechanistic basis of colonization resistance is beginning to be revealed. For instance, there has been spectacular progress in understanding which properties of the gut microbiota are required to prevent colonization of Clostridium difficile, which will facilitate the development of second generation probiotics.

In the foreword of the study you write that “exciting research is now starting to unravel how the composition of the microbiota can offer either resistance or assistance to invading pathogenic species”. How the microbiota should be ideally composed to be able to resist to invading pathogens?

One important function of the gut microbiota is to maintain homeostasis, which does not involve any specific bacteria species, but is a property conferred by the metabolites the microbial community generates. Some of these metabolites influence host immunity or host metabolism, which in turn influences the gut environment and prevents pathogen colonization.
The concept to stimulate the microbiom is fascinating. How this approach could influence therapies (especially regarding nosocomial infections such as Clostridium difficile and MRSA)?

Fecal Microbiota Transplantation (FMT) may be replaced by second generation probiotics in the future to restore colonization resistance against C. difficile after antibiotic therapy. However, therapies to maintain colonization resistance during antibiotic therapy would be necessary to curb the nosocomial spread of carbapenem-resistant Enterobacteriaceae, which are a major heath threat to hospitals world-wide. Research on colonization resistance holds the key to developing these approaches.