“Sometimes only 15-20% of the cells are responsible for producing your target product. And after 60-80 generations, cells can completely lose the ability to produce,” notes Munch, a former Novozymes executive well-versed in the economics of industrial fermentation.

“There are different factors that affect the decline in production at scale, but for every generation, there are mutants that say, ‘If I stop making target protein X, I can grow faster,’ and they will eventually take over the bioreactor.”

Which is no surprise if you think about it, says Munch, who caught it AgFunderNews at the recent SynBioBeta conference.

Microbial cells do not naturally produce milk proteins, vaccines, human milk oligosaccharides or other bioproducts that the cells are genetically engineered to express, so there is “no competitive evolutionary advantage” to making them.

He adds: “And even if all your cells are producing the target, some are really high producers and others aren’t, so you can get a really inefficient process.”

More productive bioproduction for a longer period

Enduro, a Copenhagen-based startup created by the Technical University of Denmark by Dr. Peter Rugbjerg (CSO) and Dr. it almost sounds too good to be true” when you first encounter it, says Munch.

In short, Enduro “effectively tricks cells into thinking they need to produce the target substance in order to survive,” by tying up the expression of essential genes that are critical for an organism’s survival and high production of the target. substance in a cell, adds Munch.

“Our solution [‘Enduro Sense’] it is a genetic biosensor that binds to essential genes in the cell and this means that only cells that are high producers of the target substance can grow or multiply. Essential genes are up-regulated when the cell produces the target substance and down-regulated when it does not.”

The net result is that high-productivity cells dominate the bioreactor, enabling firms to sustain bioproduction on a longer time scale, claims Munch, who says Enduro’s genetic biosensors have been tested in E. coli AND bacillus strains of bacteria to baker’s yeast and filamentous fungi, producing everything from milk proteins and mevalonic acid to antibodies used in drug development.

“A successful implementation can lead to 30%+ improvements in titer and yield and the ability to run fermentations five times longer, as you are effectively shifting the culture towards higher producing cell variants.

Enduro Sense also works completely independent of the product pathway and works with cells doing intracellular expression [where the target product is expressed inside cell] or extracellular expression [where the target product is secreted from the cell into the media].”

By making existing biomanufacturing capacity more productive, customers can also potentially avoid the capital they had planned to spend on additional or larger bioreactors, he claims.

Reverse evolution?

He adds: “We’re putting everything in reverse. Right now there is an evolutionary selective pressure against high-producing cells because it puts a burden on them. With our technology, we’re reversing that high production yields an evolutionary benefit.”

In a study conducted by the co-founder of Enduro, Dr. Rugbjerg and others at the Technical University of Denmark, researchers monitored the expression of two essential genes unconditionally with a mevalonic acid biosensor.

The resulting production organism maintained high-yield mevalonic acid production through 95 generations of cultivation, corresponding to the number of cell generations required for industrial-scale production of >200 m3, at which time the regular strain was producing nothing , says Munch.

Implementation of Enduro Sense

Applying Enduro Sense to a production type is done once at the master cell bank level and requires no changes to the media (no antibiotics, no additives) or to the production process, he says. “We don’t introduce any foreign DNA and we don’t tamper with the production path.”

First, Enduro performs an analysis of fermentation samples at different stages of a fermentation using RNA-seq (a technique that detects the presence and quantity of RNA molecules in a biological sample) and Enduro’s proprietary algorithm .

Then, it maps the core sensor gene constructs from its algorithm and library. After that, either Enduro or the customer can generate multiple variant candidates with Enduro Sense, screen and select the best ones based on phenotypic performance on shake strips, and then validate them in a bioreactor.

Some customers are happy to send their strain to Enduro, “and we do everything in house,” says Munch.

For others concerned about IP, he says, “We can send them the constructs, the sequences they need to implement this as a data file, so they can synthesize the DNA and do the transformation themselves with our guidance, and we can help them interpret the results. We’ve done implementations with customers where their strain never left their premises.”

Too good to be true?

According to Munch, who has been CEO for a year, “It seemed too good to be true when I first met it, because I saw right away that if it works, it’s fundamental game-changing technology for an industry I’ve worked in for 14 years. YEAR [at Novozymes]. It is using biology to solve a biological problem.

“When I joined, Enduro was in stealth mode. We reached out to a bunch of companies who said yes, the problem you claim to be solving is real, and if it works, it’s almost too good to be true, what’s the catch? Will it work with me? [production] host?

So we started doing projects with them and sorting out the IP and so on, and now we have deals with a number of major industry players who have fully understood that if this works, it’s a game changer.”

Enduro has “underlying IP covering product and method claims related to the exercise of this type of technology,” he adds.

Enduro secured seed funding from NOON Ventures in 2022 and has also secured grant funding from the European Innovation Council (EIC). It is now looking to raise a Series A round, Munch says.

“What investors can see is that we’re solving problems that affect everyone in organic production, whether you’re making vitamins or antibiotics. We are a tools company with a licensing and authority model, not a product company.”

Further reading:

SynBioBeta 2024: From new hosts to ‘tricking’ cells to be more productive… addressing the ‘cost-of-scale paradox’ in biomanufacturing