Harnessing Escherichia coli for Bio-Based Production of Formate under Pressurized H < sub > 2 < /sub > and CO < sub > 2 < /sub > Gases

In this study, an E. coli host strain was engineered for the continuous production of formic acid from H2 and CO2 during bacterial growth in a pressurized batch bioreactor. Incorporation of tungsten, in place of molybdenum, in FHL-1 helped to impose a degree of catalytic bias on the enzyme. This work demonstrates that it is possible to couple cell growth to simultaneous, unidirectional formate production from carbon dioxide and develops a process for growth under pressurized gases. IMPORTANCE Greenhouse gas emissions, including waste carbon dioxide, are contributing to global climate change. A basket of solutions is needed to steadily reduce emissions, and one approach is bio-based carbon capture and storage. Here, we present our latest work on harnessing a novel biological solution for carbon capture. The Escherichia coli formate hydrogenlyase (FHL-1) was engineered to be constitutively expressed. Anaerobic growth under pressurized H2 and CO2 gases was established, and aqueous formic acid was produced as a result. Incorporation of tungsten into the enzyme in place of molybdenum proved useful in poising FHL-1 as a hydrogen-dependent CO2 reductase (HDCR).PMID:34647819 | DOI:10.1128/AEM.00299-21
Source: Applied and Environmental Microbiology - Category: Microbiology Authors: Source Type: research