Key Takeaways

• Switch Bioworks initiates multi-state field trials in the Midwest to test engineered nitrogen-fixing microbes in corn.
• The trials aim to determine microbial colonization, switch activation timing, and the best microbial mix for future products.
• Commercialization is targeted in two to three years, aiming to reduce synthetic nitrogen use by up to 25% while maintaining crop yields.

Field Trials Underway

California-based Switch Bioworks has launched its first multi-state field trials for engineered nitrogen-fixing microbes in corn across the Midwest. These trials, which commenced in May, represent a significant transition from laboratory and greenhouse environments to real-world agricultural conditions. Founder Tim Schnabel, PhD, emphasized that this stage serves as the ultimate test of whether the engineered microbes can thrive and function as intended in diverse field and soil settings.

During these in-furrow trials, Switch employs a mixture of nitrogen-fixing microbes capable of naturally producing nitrogenase, an enzyme that combines nitrogen with hydrogen to generate ammonia. This approach allows farmers to significantly diminish their reliance on synthetic fertilizers. Schnabel remarked that the ammonia produced by these microbes mirrors the output of the energy-intensive Haber-Bosch process but operates efficiently at room temperature. The engineered microbes are designed to first establish themselves in the soil, after which a genetic switch activates ammonia production without requiring any farmer intervention.

Aim of the Trials

Characterized as late-stage R&D trials, these tests are focused on addressing three critical questions: the ability of the microbes to colonize corn roots, the timing of the genetic switch activation, and identifying which microbial strains will be part of the final product. Metrics being monitored include the root microbial community’s composition and abundance, the activation of the genetic switch as indicated by DNA changes, plant nitrogen response indicators, and yield outcomes. However, Schnabel noted that measurable results in nitrogen levels or crop yield are not expected this season; the primary objectives are microbial colonization and affirming the timing of switch activation.

Importance of the Genetic Switch

The process of nitrogen fixation is metabolically demanding for microbes, and Switch’s strategy seeks to ensure that engineered microbes can produce sufficient nitrogen while competing effectively with native soil microorganisms. This process involves separating the two critical functions of colonization and nitrogen production. The microbes first establish themselves on root surfaces and later switch to a state where they generate surplus nitrogen to share with the corn plants.

Schnabel highlighted that this approach addresses a significant challenge for the microbial fertilizer industry and differentiates Switch from its competitors. Unlike methods relying on natural mutants for ammonia production, Switch has engineered its microbes from the ground up, which has made acquiring regulatory approval from the USDA and EPA particularly notable. This innovative bioengineering involved integrating components from viruses and other bacteria, culminating in a unique class of biofertilizer.

Commercial Strategy

Having received the necessary permits for experimental field release, Switch aims to commercialize this technology within two to three years. While full elimination of synthetic nitrogen fertilizers is not the goal, a 25% reduction in fertilizer usage while maintaining yields would represent a significant achievement. The financial case for this product is becoming clearer, especially as geopolitical tensions disrupt global fertilizer and energy markets.

Schnabel stated that the cost-effective application of microbes could yield substantial savings for farmers, with projected reductions of $20 to $30 per acre on fertilizer expenses. Additionally, Switch is engaged in late-stage partnership discussions with various agrochemical, fertilizer, and seed companies and anticipates making announcements soon.

Gareth Asten of Acre Venture Partners, an investor in Switch, noted that these field trials mark a critical milestone in addressing the substantial challenge of reinventing fertilizer, positioning Switch as a leading contender to offer viable solutions in this domain.

The content above is a summary. For more details, see the source article.