Ionic liquid

Nanotechnology

Organic chemistry

Enzyme

Biocatalysis

Combinatorial chemistry

RuBisCO

Biology

Photorespiration

Pyruvate carboxylase

Engineering

Catalysis

Photosynthesis

Biochemical engineering

Chemistry

Synthetic biology

Materials science

Carbon fixation

Carboxylation

Ethylene glycol

Computational biology

Biochemistry

Nature Catalysis

The capture of CO 2 by carboxylases is key to sustainable biocatalysis and a carbon-neutral bio-economy, yet currently limited to few naturally existing enzymes. Here, we developed glycolyl-CoA carboxylase (GCC), a new-to-nature enzyme, by combining rational design, high-throughput microfluidics and microplate screens. During this process, GCC’s catalytic efficiency improved by three orders of magnitude to match the properties of natural CO 2 -fixing enzymes. We verified our active-site redesign with an atomic-resolution, 1.96-Å cryo-electron microscopy structure and engineered two more enzymes that, together with GCC, form a carboxylation module for the conversion of glycolate (C 2 ) to glycerate (C 3 ). We demonstrate how this module can be interfaced with natural photorespiration, ethylene glycol conversion and synthetic CO 2 fixation. Based on stoichiometrical calculations, GCC is predicted to increase the carbon efficiency of all of these processes by up to 150% while reducing their theoretical energy demand, showcasing how expanding the solution space of natural metabolism provides new opportunities for biotechnology and agriculture.

A new-to-nature carboxylation module to improve natural and synthetic CO2 fixation