Designer Microbe Reduces Mercury in Seafood
- Scientists at UCLA and UC San Diego's Scripps Institution of Oceanography have engineered a gut microbe capable of detoxifying methylmercury, a dangerous pollutant.
- The research, detailed in Cell Host & Microbe, suggests a potential probiotic solution to offset the risks of consuming to much methylmercury, particularly for pregnant women.
- Mercury, released into waterways from sources like coal burning and mining, transforms into methylmercury in the ocean.
UCLA and UC San Diego scientists engineered gut bacteria, offering a promising solution to the dangers of methylmercury, the primarykeyword. Their breakthrough involves a modified gut microbe that substantially reduces methylmercury absorption.This is especially pivotal, given the importance of fish as a dietary cornerstone and the slow decline of mercury levels in seafood, making this secondarykeyword increasingly relevant. The research, published in Cell Host & Microbe, shows the engineered bacteria effectively detoxify methylmercury, lowering levels not only in the intestine but also in the brain and liver of mice. Experiments with pregnant mice demonstrated lessened mercury levels in both maternal and fetal tissues. News Directory 3 reports on a potential probiotic that could mitigate methylmercury risks. Discover what’s next for human trials…
Engineered Gut Bacteria Detoxifies Methylmercury, Reduces Toxicity
Updated june 10, 2025
Scientists at UCLA and UC San Diego’s Scripps Institution of Oceanography have engineered a gut microbe capable of detoxifying methylmercury, a dangerous pollutant. The modified bacteria significantly reduced the amount of methylmercury absorbed into the brains and developing fetuses of mice consuming a fish-rich diet.
The research, detailed in Cell Host & Microbe, suggests a potential probiotic solution to offset the risks of consuming to much methylmercury, particularly for pregnant women.
Mercury, released into waterways from sources like coal burning and mining, transforms into methylmercury in the ocean. This toxic compound accumulates up the food chain, posing a important threat to humans who consume predatory fish like bluefin tuna.
Amina Schartup, scripps associate professor of marine biogeochemistry, noted that despite efforts to curb mercury emissions, methylmercury levels in seafood are not expected to decline rapidly. She emphasized the importance of fish as a dietary staple for many cultures.
The researchers modified bacteroides thetaiotaomicron, a common human gut bacterium, by inserting DNA that encodes mercury detoxification enzymes. Tests showed the engineered bacteria effectively cleared methylmercury in test tubes. When introduced into mice, the modified bacteria significantly reduced methylmercury levels in their intestines within hours, with levels continuing to decline over four days.
Further studies involved feeding mice diets containing bluefin tuna. The engineered bacteria not only reduced mercury in the intestine but also decreased the amount reaching the brain and liver.
Experiments with pregnant mice revealed lower methylmercury levels in both maternal and fetal tissues, along with reduced signs of mercury toxicity in the fetal brain.
according to UCLA research scientist and first author Kristie Yu, the gut bacteria helped eliminate dietary methylmercury before it could enter the maternal bloodstream and affect the developing offspring.
UCLA researcher Franciscus Chandra added that the reduced toxicity signs in the fetal brain indicate the bacterium’s biological effectiveness.
The bacterium proved effective even with salmon, which contains lower methylmercury levels than bluefin tuna. Moreover, when administered as an oral probiotic to mice with intact microbiomes, the engineered bacteria still minimized methylmercury absorption into tissues.
Elaine Hsiao, UCLA associate professor and director of the UCLA Goodman-Luskin Microbiome Center, envisions a future where people can take a probiotic to mitigate methylmercury risks.
What’s next
Hsiao and schartup are focused on enhancing the bacterium’s efficacy and progressing toward human trials, contingent upon continued federal funding.