Despite its increasing antiquity, Pac-Man's 8-bit graphics — and gameplay — continue to grip imaginations across generations. The sphere-shaped protagonist consumes dots and fights pesky, pixelated ghosts.
Now, keep that visual in mind.
Researchers at University of Waterloo in Ontario have figured out a way to engineer bacteria into doing just that with tumors — an enemy much more harmful than a digital specter.
Here’s how it works: The inside of a tumor has plenty of nutrients and no oxygen, creating a paradise for the specially engineered microbes. The little bacteria eat and eat until they grow big enough to take over the unwanted mass.
Our hero in this approach is Clostridium sporogenes, a bacterium typically located in soil, whose survival is predicated upon there being no oxygen to disrupt its existence. This is why it can thrive in a place with no air — like the inside of a tumor.
At first, the bacteria would die off as they ate closer to the edges of the tumor, where small amounts of oxygen are often present. To combat this, scientists added a relative of Clostridium sporogenes that can better tolerate oxygen — allowing the engineered bacteria to survive longer and get the job done.
To prevent them from growing toward areas rich in oxygen, like the bloodstream, researchers also developed a control system for the bacteria to grow to a certain amount before their “oxygen-seeking” or “oxygen-tolerant” behaviors kicked in.
Next steps will include combining both of these behaviors into a single bacterium and taking it from the lab to testing it on tumors in clinical trials.
All in all, the 1980s would be proud.
