Bioethics Blogs

Creative Minds: The Human Gut Microbiome’s Top 100 Hits

Michael Fishbach

Microbes that live in dirt often engage in their own deadly turf wars, producing a toxic mix of chemical compounds (also called “small molecules”) that can be a source of new antibiotics. When he started out in science more than a decade ago, Michael Fischbach studied these soil-dwelling microbes to look for genes involved in making these compounds.

Eventually, Fischbach, who is now at the University of California, San Francisco, came to a career-altering realization: maybe he didn’t need to dig in dirt! He hypothesized an even better way to improve human health might be found in the genes of the trillions of microorganisms that dwell in and on our bodies, known collectively as the human microbiome.

Fischbach is most interested in bacteria living in the human gut, especially the many species that generally live in harmony with us. These microbes produce thousands of small molecules, some so abundantly that they are absorbed into the bloodstream at levels comparable to a drug. Concentrations of these small molecules can vary dramatically from person to person, but researchers still don’t know exactly why.

Fischbach has received a 2016 NIH Director’s Pioneer Award to conduct research aimed at gaining a better understanding of the small molecules made by the human gut microbiome. He will begin by creating a “Top 100” list of its most-abundant molecules. Armed with this information, Fischbach’s team will set about assembling and growing beneficial communities of bacteria in the lab, with the ultimate aim of repopulating a sick person’s gut with a collection of microbes that make health-promoting small molecules.

The views, opinions and positions expressed by these authors and blogs are theirs and do not necessarily represent that of the Bioethics Research Library and Kennedy Institute of Ethics or Georgetown University.