Capture of carbon dioxide and hydrogen by engineered Escherichia coli: hydrogen-dependent CO(2) reduction to formate

ABSTRACT: In times of global climate change and the fear of dwindling resources, we are facing different considerable challenges such as the replacement of fossil fuel–based energy carriers with the coincident maintenance of the increasing energy supply of our growing world population. Therefore, CO(2) capturing and H(2) storing solutions are urgently needed. In this study, we demonstrate the production of a functional and biotechnological interesting enzyme complex from acetogenic bacteria, the hydrogen-dependent CO(2) reductase (HDCR), in the well-known model organism Escherichia coli. We identified the metabolic bottlenecks of the host organisms for the production of the HDCR enzyme complex. Here we show that the recombinant expression of a heterologous enzyme complex transforms E. coli into a whole-cell biocatalyst for hydrogen-driven CO(2) reduction to formate without the need of any external co-factors or endogenous enzymes in the reaction process. This shifts the industrial platform organism E. coli more and more into the focus as biocatalyst for CO(2)-capturing and H(2)-storage. KEY POINTS: • A functional HDCR enzyme complex was heterologously produced in E. coli. • The metabolic bottlenecks for HDCR production were identified. • HDCR enabled E. coli cell to capture and store H(2) and CO(2) in the form of formate. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s00253-021-11463-z.