(532b) Metabolic Engineering of E. coli for Ethylene Glycol Production from C1 Compounds

In the quest for sustainable industrial practices, the traditional chemical industry, with its heavy reliance on fossil fuels and saccharide resources, faces significant challenges. These practices not only contribute to the exacerbation of greenhouse gas emissions but also pose substantial environmental risks and compete with the food industry, thus jeopardizing food security. In this context, one-carbon (C1) compounds like carbon dioxide (CO2), carbon monoxide (CO), methane (CH4), formaldehyde, methanol, and formic acid emerge as promising alternatives. Their abundant availability, cost-effectiveness, and reduced environmental footprint position them as viable raw materials for the next generation of high-value-added chemicals, including bioenergy, biomaterials, and biopharmaceuticals, fostering the sustainable and circular use of carbon resources.

Ethylene glycol (EG), a pivotal bulk chemical in the synthesis of biodegradable plastics and as a constituent in antifreeze and coolant applications, stands at the forefront of this transition. The development of a green, efficient, and economically viable pathway for EG synthesis is not just a scientific endeavor but a necessity for industrial sustainability. Traditional biosynthetic approaches for EG, predominantly based on sugar fermentation, face hurdles like by-product separation, low substrate conversion rates, and extensive pathway steps, necessitating alternative routes.

This research delves into the utilization of soluble C1 compounds—formaldehyde, methanol, and formic acid—for EG production. By optimizing the C1 compound utilization pathway and enhancing the supply of reducing equivalents, we aim to achieve a higher metabolic flux and titer of EG. Our work evaluates various enzymes in the pathway, specifically focusing on glycolaldehyde reductase and aldehyde dehydrogenase, and explores the innovative use of formate and methanol as sole carbon sources for EG production.

Our approach not only offers a pathway to sustainable chemical manufacturing but also provides insights into the utilization of C1 compounds, potentially setting a precedent for the production of other high-value chemicals.