Metabolic engineering of acetogens for production of low carbon fuels and chemicals from waste gases

In December 2015, 195 countries adopted the Paris Agreement at the United Nations Climate Change Conference. The agreement “aims to strengthen the global response to the threat of climate change” and seeks to hold the increase in global average temperature to “well below 2 °C above pre-industrial levels”.

LanzaTech’s novel gas fermentation technology recycles greenhouse gases for production of fuels and chemicals, contributing to meeting the threat of climate change. In contrast to traditional fermentation that uses sugars as a substrate, gas fermentation utilizes acetogenic bacteria capable of fixing C1 substrates carbon monoxide (CO) or CO₂. While the potential of acetogens has been recognized for decades, development has been limited by the lack of genetic tools. LanzaTech has overcome these challenges and rapidly developed a robust genetic toolbox for acetogens comprising genome editing tools, libraries of genetic parts, design algorithms, a validated genome-scale model, and automated strain engineering workflows.

Using this platform, synthesis of over 25 non-native molecules has been demonstrated directly from gas. Examples include acetone, isopropanol or butanol via combinatorial testing and optimization of genes from the commercial ABE fermentation process. Yields and production rates achieved on gas have exceeded those of native producers utilizing sugars or published examples of E. coli or yeast engineered for these products. In addition to these known routes, LanzaTech is also developing de novo routes to products including 1,3-butanediol, butadiene and isobutylene. Currently, LanzaTech is constructing first commercial unit in Europe and Asia that will use off gases from the steel industry.