Advanced BioFuels USA

 by Fungmin Eric Liew (Lanza Tech/Nature Bioengineering Community)  Industrial waste gas can serve as feedstock to manufacture fuels and chemicals through gas fermentation. Our work describes a collaborative and multidisciplinary team effort to engineer gas-utilizing microbe to produce acetone and isopropanol at industrial pilot scale in a carbon-negative fashion.

Back in 2008, in an underground laboratory in Auckland, New Zealand, an unconventional type of fermentation was brewing. Instead of utilizing sugars as carbon and energy source, a group of scientists and engineers was training microbes known as acetogens to gobble up waste gas (containing CO₂, CO and H₂) from a local steel mill, and spit out fuels and chemicals. Fresh out of university, I was amongst the first 20 employees of LanzaTech and was tasked with characterizing these acetogens at the molecular level and developing genetic tools to make novel chemicals. The entire field of gas fermentation was in its infancy and literature on successful genetic engineering of acetogens was non-existent. Dr. Michael Köpke and Dr. Ching Leang are early pioneers in this field and both joined LanzaTech to propel this field to new heights.

One of the first tasks that I was given when I joined LanzaTech was to screen an industrial clostridial collection of ABE (­Acetone-Butanol-Ethanol) strains reaching back to the 1940s assembled by Prof. David Jones (University of Otago). Little did I know that this microbial collection would one day be genome-sequenced (by the DOE Joint Genome Institute) and form the basis of a multidisciplinary collaboration between Northwestern University (cell-free prototyping and kinetic modelling), Oak Ridge National Laboratory (multi-omics) and LanzaTech to develop a gas-to-acetone/isopropanol process.

…

Published in this month’s Nature Biotechnology, our paper “Carbon-negative production of acetone and isopropanol by gas fermentation at industrial pilot scale” describes the use of genes mined from the David Jones collection to construct an acetone combinatorial pathway library.

…

Since 2014, LanzaTech is headquartered in Chicago, IL, and currently operates two full-scale commercial plants converting industrial off-gas to ethanol with a by-product of high protein biomass (for animal feed), with 7 plants planned to come online across the globe by year 2022, utilizing a variety of feedstocks including municipal solid waste, agricultural waste, and carbon emissions from industries. In addition to being a drop-in fuel, ethanol has been purified and upgraded into a range of CarbonSmart^TM products that are accessible to today’s consumers: fragrance, household cleaning products, sustainable packing and fashion. Furthermore, ethanol has been chemically upgraded to paraffins and isoparaffins for use as sustainable aviation fuel and used in two transoceanic flights in 2018 and 2019. Scaling up bioprocesses is challenging and it’s been a privilege to see microbes developed in the lab being deployed at half million-liter tanks around the world and we are excited to see acetone and isopropanol strains deployed next in these plants.

Life cycle analysis (LCA) confirmed a negative carbon footprint for the products.   READ MORE

Three partners, two problems, one bioenergy research article published (U.S. Department of Energy)