"Arsenic Detoxification by the Human Gut Microbiome"
Seth Walk (Montana State University)
Arsenic is a toxin and human carcinogen, ranking first on the Priority List of Hazardous Substances from the US Agency for Toxic Substances and Disease Registry. Inorganic arsenic in drinking water is transformed in the body to a variety of arsenic-containing compounds (arsenicals) that differ in toxico- and carcinogenic properties. Most research on arsenic metabolism in mammals has focused on mammalian cells. The focus of our research is on microbial arsenic metabolism, specifically in the gastrointestinal tract. Using a combination of transgenic, germ free, and gnotobiotic murine models, we discovered that the gut microbiome of mice and humans is indeed an important “organ” for decreasing the toxic effects of arsenic. The gut microbiome has to potential to detoxify arsenic in a number of ways, ranging from the production of arsenic-active enzymes to the production of small molecule metabolites that promote fecal excretion of arsenic. An overview of this research will be presented.