Overview

• Scientists have genetically modified a common gut bacterium, Bacteroides thetaiotaomicron, to break down toxic methylmercury in the digestive tract before it enters the bloodstream.
• In mouse studies, the engineered bacteria rapidly reduced methylmercury levels in the gut and tissues, including the brain and liver, with sustained efficacy during chronic dietary exposure to mercury-laden seafood like tuna and salmon.
• Pregnant mice treated with the probiotic showed lower mercury levels in maternal and fetal tissues, as well as reduced neurotoxic effects in fetal brains, highlighting its potential for protecting vulnerable populations.
• The engineered microbe retained its detoxification ability when administered as an oral probiotic alongside intact native microbiomes, suggesting a practical delivery method for human use.
• Researchers are now focused on optimizing the treatment for human trials and addressing accessibility challenges, particularly in regions heavily reliant on seafood where mercury exposure is prevalent.