Life Science Paradigm Challenge

Bacteria can hijack and 'reset' your internal biological clock.

April 15, 2026

Original Paper

An unrecognized host response to microbial exposure resets circadian timing

Mo, D.; Lam, T.; Baker, E.; Fraser, O. P.; Dorling, J.; O'Neill, J. S.; van Ooijen, G.; Dodd, A. N.; Partch, C. L.; Crosby, P.; Kimmey, J. M.

bioRxiv · 10.64898/2026.04.11.717924

AI-generated illustration

The Takeaway

We always assumed our internal clocks were strictly governed by light and temperature, but it turns out the microbes around us have a seat at the table. Researchers found that simply being exposed to soluble bacterial components can directly 're-time' mammalian cellular clocks. This happens through a hidden pathway that bypasses the usual systems we thought were in charge of our 24-hour rhythm. It means your 'jet lag' or sleep issues might not just be about light exposure, but about the specific bacteria your body is dealing with. This opens a wild new door into how our microbiome dictates our daily energy and metabolism. Your gut might be telling your brain what time it is.

From the abstract

As ubiquitous features of every natural environment, microbes have profoundly shaped eukaryotic biology throughout evolution. Circadian clocks evolved in all domains of life as central regulators that align physiology with environmental cycles, yet whether they respond directly to microbial signals remains unknown. Here, we demonstrate that evolutionarily diverse microbes potently reset mammalian cellular clocks and can drive phase shifts in plants and algae, indicating cross-kingdom effects of