Nathan Crook, an associate professor at North Carolina State University, and his team studied how the probiotic yeast Saccharomyces boulardii (Sb) behaves in the gut to inform new ways to deliver therapeutic molecules. They chose Sb because it is the only yeast species used as a probiotic, yet its biochemical activity in the gut was not well understood.
For the experiments the researchers introduced an off-the-shelf, non‑modified Sb strain into germ-free mice and collected fecal and intestinal samples. They combined established sampling and analytical techniques in a novel way to measure the RNA produced by the yeast as it passed through the animals. With no other microbes present, the yeast RNA was easier to identify.
The team found genes that are more likely to be active in the gut than in other environments. Some of these active regions include promoter sections that can act as on-switches. Targeting those promoters could tell engineered yeast when to start making therapeutic molecules, improving drug delivery. Genes linked to potentially pathogenic behaviour were not activated, which supports Sb's safety and justifies further engineering. Gene activity also suggested the gut is not nutrient-rich for Sb; the yeast used more lipids than carbohydrates, so the researchers suggest modifying Sb to use complex carbohydrates to fuel production. The paper appears in BMC Genomics and the authors have filed patent applications and invention disclosures. Support came from the National Science Foundation, the Novo Nordisk Foundation, and the National Institutes of Health.
Difficult words
- probiotic — microorganism that gives health benefit
- strain — a specific variety of microorganism
- germ-free — without other microbes or germs present
- promoter — section of DNA that acts as on-switch
- pathogenic — able to cause disease in a host organism
- lipid — type of fat molecule in cellslipids
- therapeutic — used to treat or help an illness
- patent — legal right to control an invention's use
Tip: hover, focus or tap highlighted words in the article to see quick definitions while you read or listen.
Discussion questions
- Do you think using engineered probiotic yeast to deliver medicine is a good idea? Why or why not?
- How could changing Sb to use complex carbohydrates affect its ability to work in the gut?
- What safety checks would you ask researchers to do before giving engineered yeast to people?
Related articles
Sudan turns to AI as health system struggles
Sudan’s health system is under severe strain after an almost two‑year civil war. A senior health official says the country is using artificial intelligence to help provide care where normal services no longer reach, while shortages and attacks worsen the crisis.
Brain differences in WTC responders with PTSD
New imaging research of World Trade Center responders finds measurable brain structure differences linked to long-term PTSD. Researchers used gray-white contrast (GWC) MRI and other markers to distinguish responders with and without PTSD.
Vitamin C may protect reproductive health from potassium perchlorate
A study using Japanese rice fish (medaka) found that potassium perchlorate damaged testes and reduced fertility. Fish given vitamin C alongside the chemical showed better fertility and less testicular harm, suggesting vitamin C may help protect reproductive health.
