Scientist developing bacterial sensors to monitor gut health, fix imbalances

That “gut feeling” humans experience on a regular basis is a real thing. Research has shown the link between the balance of trillions of bacteria living in our gut (microbiome) and our emotions. When the microbiome is out of balance, mental health can be affected. A recent project, driven by personal experience, focuses on developing genetically engineered bacteria with sensors to monitor chemical production in the gut and fix imbalances. 

Tae Seok Moon, associate professor in the Department of Energy, Environmental & Chemical Engineering at the McKelvey School of Engineering at Washington University in St. Louis, has experienced microbiome imbalance himself. “It is a difficult job to do,” Moon says in a statement, “to keep your neurotransmitters balanced.” 

Moon has developed other sensors, but none are specific to certain bacteria or chemicals. He says, “specificity in engineering is one of the big challenges, but we have proved that this can be done.”

This new development is a “bacterial sensor” capable of not only detecting specific chemicals in the gut, but fixing the chemical imbalances as well. Moon’s team used computer modeling to develop a sensor pathway specific to only the certain molecules they targeted. They injected the sensors into genetically engineered bacteria and observed the ability of the sensors to distinguish between similar molecules found in food and in the gut. 

Specific Protein Regulators

Using these findings, Moon’s lab can now focus on developing a protein that will respond according to the sensor’s information. For example, the sensor in an engineered bacteria could detect too much phenylalanine, which can lead to PKU – a genetic disease in babies. The same sensor could contain an actuator to lower the phenylalanine levels. 

An illustration of the forced evolution leading to specific sensor pathways. (Courtesy: Moon Lab)

These lab-created organisms can lead to many more developments within the medical community and outside of it as well. Medical treatments, quality of food, and fuels are just a few of the areas that could benefit from this new tool. 

Moon is most interested in bacteria sensors specific to neurotransmitter levels in the gut. “If the levels are too high, the bacteria produce an enzyme that degrades the target chemical. If it’s too low, the bacteria produce an enzyme that can synthesize more of it,” he says. 

Bacteria in the gut are responsible for about 95% of the serotonin released in the body. A person can be negatively impacted when it’s out of balance, according to Moon. He wants to put an end to this suffering. “This is the beginning of our engineering solution,” he says. 

Moon’s research is published in Cell Systems.

Leave a Comment