Newly Isolated Human Gut Bacterium May Counteract Effects of Metabolic Disorders

microbiome, intestinal bacteria, gut
Investigators examined the impact of D welbionis on metabolism and features of obesity in mice with diet-induced obesity and diabetes.

A novel butyrate-producing bacterium isolated from the human gut appears to have beneficial effects on host metabolism and may prevent diet-induced obesity, according to study data published in Gut.

In a prior study, investigators isolated and described Dysosmobacter welbionis J115T (D welbionis), a human gut bacterium. To further explore the abundance of this bacterium and its impact on host metabolism, investigators analyzed fecal microbiota samples from participants in 4 separate cohort studies: the Human Microbiome Project, American Gut Project, Flemish Gut Flora Project, and Microbes4U.

Additionally, mouse models were used to assess the metabolic effects of supplementation with D welbionis. High-fat diet (HFD)-fed mice were administered a daily gavage of D welbionis for up to 13 weeks. Weight gain and markers of metabolic function were measured over the study period. Characteristics of bacteria-supplemented mice were compared with control mice given the same diet.

Fecal microbiota samples from 11,984 human subjects were analyzed. Overall, D welbionis was detected in 62.7-69.8% of the general population. In participants with obesity and metabolic syndrome, the abundance of the Dysosmobacter genus was negatively associated with body mass index (BMI), fasting glucose levels, and glycated hemoglobin levels.

In mouse trials, daily administration of D welbionis appeared to partially counteract the effects of a high-fat diet. Specifically, D welbionis decreased HFD-induced weight gain by 29% compared with those not given bacterium supplementation. D welbionis mice also had improved glucose tolerance, lower rates of insulin resistance, and lower likelihood of white adipose tissue hypertrophy and inflammation. Finally, live D welbionis appeared to prevent brown adipose tissue whitening, increase the number of mitochondria, and elevate overall body temperature. These changes are all associated with improved metabolism and energy expenditure.

Mouse microbiota conditions did not appear to be substantially altered by D welbionis gavages. Pasteurization of D welbionis was found to neutralize its positive effects; mice given pasteurized bacteria did not experience improvements in body weight and fat mass.

Taken together, these results suggest that D welbionis J115T directly benefits host metabolism and is prevalent in a significant proportion of the general population. Additional research is necessary to further the medical understanding of this genus.

“These results suggest that D. welbionis J115T…is a strong candidate for the development of next-generation beneficial bacteria targeting obesity and associated metabolic diseases,” investigators wrote.

Disclosure: Several study author(s) declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures. 


Le Roy T, Moens de Hase E, Van Hul M, et al. Dysosmobacter welbionis is a newly isolated human commensal bacterium preventing diet-induced obesity and metabolic disorders in mice. Gut. Published online June 8, 2021. doi:10.1136/gutjnl-2020-323778