At the University of California San Diego, researchers have 3D-printed an “engineered living material” that neutralizes organic pollutants in water, then can be dissolved by a common nontoxic compound.

The scientists made a polymer—a long molecule made of repeating chemical units—out of seaweed.

Next, they populated the polymer with a bacterium engineered to make an enzyme that neuters a range of organic pollutants, rendering them benign.

The bacterium also was designed to dissolve in the presence of a small molecule called theophylline, which is present in trace amounts in several foods, including chocolate, coffee, and tea. 

Theophylline produces a protein that causes the bacteria’s cells to fall apart into harmless substances. That step was added to eliminate worries about engineered bacteria being loosed into the wild.

The developers began with alginate, a polymer in seaweed. They turned the alginate into a gel and mixed in a bacterium that lives in water and supports itself through photosynthesis. 

The scientists engineered the bacteria to make the enzyme laccase, which is known to neutralize a range of water pollutants from pharmaceutical drugs to bisphenol A (BPA), a hormone disruptor.

After testing various structures in a 3D printer, they found the one that did the best job of keeping the bacteria alive and holding the bugs close to the polymer’s surface.

In an initial test, the process neutralized the blue dye the textile industry uses to color denim.

Next, the developers are looking for a way to make the bacteria self-destruct without the aid of an external additive.

TRENDPOST: Scientists have discovered that bacteria can be genetically engineered to do almost anything. One strain of bugs is producing pharmaceutical drugs; another eats and digests explosives.

Bacteria don’t tend to grab headlines but their presence in manufacturing, medical treatment, environmental clean-up, and other areas is becoming as powerful as AI is in telecommunications.