Novel gas fermentation approach enables engineered microbes to eat greenhouse gases and produce valuable products for multiple uses
By Lindsay Brownell
(BOSTON) — The Wyss Institute for Biologically Inspired Engineering at Harvard University announced today that Circe, a startup developed at the Institute and spun out of Harvard, has signed a worldwide, exclusive licensing agreement coordinated by Harvard’s Office of Technology Development (OTD) to commercialize a novel bioproduction technology that could significantly reduce the carbon emissions of industries from food to aviation fuel.
Circe has raised more than $8 million to date from investors including Regen Ventures, Undeterred Capital, Ponderosa Ventures, Bee Partners, Elementum Ventures, Exceptional Ventures and Safar Partners.
“One of the great challenges humanity faces is how to maintain global growth and production and decarbonize everything at the same time. Circe is addressing this critical problem by using gas fermentation to manufacture the products and molecules we need in a carbon-negative way,” said Shannon Nangle, Ph.D., who co-founded Circe along with fellow Wyss member Marika Ziesack, Ph.D.
Developed in the lab of Wyss Core Faculty member Pamela Silver, Ph.D., Circe’s technology grows microbes on gasses like carbon dioxide — in the same way plants grow — and harvests the molecules they build. Nangle and Ziesack used synthetic biology to tweak the metabolisms of certain microbes that naturally “eat” greenhouse gasses so that they use those gases to manufacture molecules that are valuable to many industries. Their platform has produced molecules identical to those that make up sugars, fats, biodegradable plastics, and biofuels, all using only CO2, water, and electricity as inputs.
“In order to ensure that the Earth is habitable for future generations of humans, we urgently need to decarbonize industries and start reversing the damage we’ve caused to the planet. Microbes are wonderful living machines that we can leverage to produce the things we need for everyone to live a happy, comfortable life while reducing pollution, land use, and fossil fuel consumption,” said Silver, who is also the Elliot T. and Onie H. Adams Professor of Biochemistry and Systems Biology at Harvard Medical School (HMS).
Circe’s first products in development are triglycerides: the molecules that make up the fats, butters, and oils that we eat and use every day. The team has used their triglycerides to make the world’s first gas fermentation-derived chocolate, which – given the worldwide shortage of cocoa in the 2023-2024 growing season – could provide a solution to global food supply chain interruptions. In addition, this proof-of-concept enables the production of food products in any region, reducing the industry’s carbon footprint.
The Circe team is also exploring other types of fats, including milkfat that can add creaminess to both dairy and non-dairy milk products, and palm oil that can be used across the food and cosmetics industries, as well as for sustainable fuels.
Circe’s fermentation platform was created and significantly de-risked at the Wyss Institute through the Institute’s validation pipeline, which provides aspiring entrepreneurs with the resources and support they need to transition their teams and technologies from the lab to the real world. Based on its potential for significant positive impact, it was named an Institute Project in 2021 and provided additional support from the Wyss to expedite its commercialization.
Over the course of Circe’s development, the team won several accolades in recognition of its innovative concept. While at the Wyss, they were awarded $3.2 million from the US Department of Energy’s ARPA-E ECOSynBio program, and Nangle and Ziesack were named 2021 Activate Fellows. After the company spun out of Harvard, Nangle was named an “Innovator Under 35” by MIT Technology Review.
“For centuries, humans’ relationship with Nature has been dominated by extraction, destruction, and consumption. A paradigm shift to one of conservation, regeneration, and co-production using Nature’s building materials rather than harsh chemicals is starting to happen, but at much too slow a pace. The Circe team’s technology has the potential to speed up the transition to a future in which we work with Nature to produce what we need, rather than exploiting it,” said Don Ingber, M.D., Ph.D., the Wyss Institute’s Founding Director. Ingber is also the Judah Folkman Professor of Vascular Biology at HMS and Boston Children’s Hospital, and the Hansjörg Wyss Professor of Bioinspired Engineering at Harvard’s John A. Paulson School of Engineering and Applied Sciences (SEAS).