Bacteria breakthrough: UV light superpower helps produce 70% more cellulose

A research group at ETH Zurich developed a groundbreaking method to increase cellulose production in a bacterium known as Komagataeibacter sucrofermentans by 70 percent.

The well-known microorganism makes the material naturally but not fast enough. Researchers from ETH investigated how to ramp up this natural production process with a sustainable aim to meet industrial demands.

The team led by André Studart, Professor of Complex Materials at ETH Zurich turned to the laws of nature to perfect their approach. Producing 40,000 variants of the bacterium very quickly, they found four strains that became mini-factories, according to ETH Zurich.

Studart explained that “we are the first to use such an approach to improve the production of non-protein materials.”

“For me,” he continued, “this work is a milestone” that stands to impact large industries such as textiles, medicine, and even shipping.

Turning a bacterium into a super-factory

A materials researcher in Studart’s group, Julie Laurent, used UV-C light to reproduce occurring mutations in the bacterium, called “the wild type.” By damaging the DNA, in a dark room, the bacterium couldn’t heal, which in turn generated these variants.

Encased in a droplet of nutrient solution, each bacterial cell could start producing cellulose, as per ETH Zurich. Using fluorescence microscopy, a light source that stimulates a fluorescent molecule in the subject, she assessed which variants succeeded in generating desirable amounts of cellulose.

The ETH material research team teamed up with ETH chemist Andrew de Mello to sort through the cells. As a system created by de Mello’s group, “it can scan half a million droplets with a laser in a matter of minutes.” Out of a large batch, they identified four that made 50-70% more cellulose. They shared the same genetic mutation, but it had nothing to do with the genes that control cellulose production.

“We suspect that this protease degrades proteins that regulate cellulose production. Without this regulation, the cell can no longer stop the process,” Julie Laurent told ETH Zurich.

Altered states of bacteria produce cellulose mats

K. sucrofermentans produces “high-purity cellulose.” It is a much sought-after biomaterial for its antiseptic properties which is one of its applications in medicine: wound dressing.

As it only requires some air and water, it’s sustainable. Thus, researchers have been hard at work figuring out how to turn this bacterium into a “mini factory.” However, it can’t produce much very quickly.

So, ETH Zurich researchers tapped into the cells’ inner mechanisms to boost their output and succeeded.

They can also apply it to other types of bacteria since they can be engineered to build usable materials . They’ve patented the approach, given the collective effort on behalf of researchers to crack this code.

Up next, they plan to test out the super-bacteria in industrial settings to evaluate in practical conditions, ETH Zurich concludes .