Postdoc Steven Frese Honored by the European Probiotics Association


The European Probiotics Association awarded Foods for Health Institute postdoctoral researcher Steven Frese the 2014 Jules Tournut Probiotics Prize for his Ph.D. work. As a graduate student at the University of Nebraska, Frese conducted research in the lab of Jens Walter on host-specificity among vertebrate gut symbionts.

In Walter’s Lab, Frese and others studied how a species of Lactobacillus in vertebrate animal hosts evolved to live in different host animals. Using comparative genomics, Frese was able to determine that bacteria pursue different lifestyles that correspond to the physiology of the host; this is the first time someone found host-specificity among vertebrate gut symbionts. Frese worked with Gerald Tannock’s team in New Zealand using gnobiotic, germ-free, mice to confirm how one particular bacterial gut symbiont, Lactobacillus reuteri, behaved distinctly in mice by forming a biofilm unique to rodent stomachs.

Jens Walter, now Associate Professor and CAIP Chair for Nutrition, Microbes, and Gastrointestinal Health in the Department of Agricultural, Food & Nutritional Science/Department of Biological Sciences at the University of Alberta, notes that Frese’s Ph.D. work made “major contributions to our understanding of the biology and evolution of symbiosis between vertebrates and their gut microbe."

Most broadly, Frese was able to show that host adaptation and host specificity are important aspects of host and microbial interaction, and as a result, it is crucial to understand where a particular strain of Lactobacillus comes from if it is intended for use as a human probiotic. This has powerful implications in understanding the nutritional impact of various beneficial bacteria currently used as probiotics, and in filling the knowledge gap on exactly how probiotics work in the human body.

The European Probiotics Association recognized Frese’s research to bring about a more rigorous and mechanistic understanding of how probiotics work by awarding him this prestigious international prize. Frese says he was both surprised and honored to receive the Jules Tournut Probiotics award, which he submitted at the urging of UC Davis Professor David Mills.

As a postdoctoral researcher in Dave Mills Lab, Frese is using a pig model for understanding infant gut diseases. Working with Chris Calvert in the Department of Animal Science and Daniela Barile in the Department of Food Science & Technology, Frese is researching how milk glycans are degraded in the gut, by “who,” and by what mechanism. Frese is looking to answer these questions using a pig model to conduct studies that cannot be completed in human infants.

Frese says that this kind of work, which is both mechanistic and translational, is something he appreciates about working with Dave Mills. In turn, Mills believes that Frese is a talented addition to UC Davis, and will further enrich the exciting research that makes up the Foods for Health Institute.