Switch Bioworks, a Stanford spinout that engineers microbes to produce nitrogen fertilizer on the corn root, announced a collaboration today with Bayer Crop Science on its genetic switch technology. Nitrogen fixation is the first focus.
What it describes is a partnership to develop “next-generation biologicals that deliver clear benefits to growers.” The company did not disclose financial terms or the scope of the deal.
Why a partner matters at this stage
Switch has USDA and EPA authorization for first-in-class field trials of its engineered microbial fertilizer, now underway at multiple sites across the Midwest. Its technology is protected by seven patent families. The company also reports approvals in Brazil from the country’s National Technical Biosafety Commission (CTNBio).
Bayer brings the downstream pieces.
“We do that by complementing their expertise with our capabilities in product development, formulation, field testing and commercialization, as well as our understanding of crop genetics,” Benoit Hartmann, Insights, Innovation & Partnerships Lead at Bayer Crop Science said in the company’s announcement.
Switch CEO Tim Schnabel describes the company’s own gaps on the Top Producer Podcast.
“I’m great at engineering microbes for ammonia, but building a company is a whole other endeavor,” he says.
How the switch works
Microbes engineered to make nitrogen can struggle to establish on the root, while microbes that establish reliably often don’t make enough to matter to a grower.
Schnabel lays out the mechanism his company has developed—microbes to make nitrogen fertilizer. Most microbes that can make ammonia–the active ingredient in nitrogen fertilizer–and keep it for themselves.
“They don’t share it with the plants,” he says. “They don’t have a reason to do it.”
Forcing them to share has a cost.
“This microbe has a fitness tax,” Schnabel explains. “It’s providing ammonia to the plant for free, and that fitness tax prevents it from thriving in field soil.”
Switch’s answer is to delay production.
“We have figured out how to get microbes to share ammonia with plants, so they can use it as fertilizer, but also we can control the timing of that, which allows the microbial product to establish itself on plant roots before it starts making that fertilizer,” he says. “We have encoded into there for the microbe to notice when the nitrogen in the soil drops below a certain level.”
The trigger is genetic. In his example, a grower plants corn with about half the usual nitrogen. As the plant draws that down, the microbes already on the root notice, the switch turns on and they supply the rest. He said production switches on at about V6 to V8.
In grow-room studies, the company says, that programming produced five times more nitrogen than strains that are always producing.
What a grower can plan around
“We don’t think that a biological will ever be able to replace all nitrogen fertilizer,” he says. “We’ve run some models on the back end, and we think we can get [to] 50%.”
The first product is not waiting for that target as the company wants to go to market as soon as possible and its first commercial product targets a 25% replacement.
On cost, he says the microbes are grown in fermenters and spray-dried into a shelf-stable powder.
“It is significantly cheaper than chemical nitrogen,” he says, and manufacturing cost “is going to come down to just a couple of dollars an acre.”
The rest of the margin, he says, would be split between the grower and the sales channel, which the company does not plan to bypass.
Current timeline for a commercial release indicates 2029.
Schnabel also says Switch is not trying to replace the fertilizer system.
“Not to fully replace what we’re currently doing. That’s been successful for over a century now, but just to provide another source that farmers could use to stabilize what they spend on nitrogen,” he says.
