Development of a novel carbon fixation pathway enabled by protein engineering

Abstract

Metabolic engineering in conjunction with computational protein design has the ability to expand the range of possible metabolic pathways. As a demonstration of this utility, a novel one-carbon assimilation pathway, the Formolase pathway, was implemented in Escherichia coli using a computationally designed enzyme. This pathway was designed to address a need for more sustainable feedstocks for biochemical production. With the documented ability to produce formate from carbon dioxide, this efficient, linear pathway allows for carbon sequestration and utilization through transformation to chemicals or fuels in industrial hosts that do not naturally fix carbon. The development of formolase, a carboligase, through computational protein design enables this pathway by joining 3-1C molecules into 1-3C molecule that accesses glycolysis via phosphorylation. This glycolytic flux can become any number of biochemical products using well-characterized production pathways. In this work, in vitro function of the formolase pathway is presented and efforts to improve pathway function are detailed.