Direct 1,3-butadiene biosynthesis in Escherichia coli via a tailored ferulic acid decarboxylase mutant

Abstract

The C4 unsaturated compound 1,3-butadiene is an important monomer in synthetic rubber and engineering plastic production. However, microorganisms cannot directly produce 1,3-butadiene when glucose is used as a renewable carbon source via biological processes. In this study, we construct an artificial metabolic pathway for 1,3-butadiene production from glucose in Escherichia coli by combining the cis,cis-muconic acid (ccMA)-producing pathway together with tailored ferulic acid decarboxylase mutations. The rational design of the substrate-binding site of the enzyme by computational simulations improves ccMA decarboxylation and thus 1,3-butadiene production. We find that changing dissolved oxygen (DO) levels and controlling the pH are important factors for 1,3-butadiene production. Using DO–stat fed-batch fermentation, we produce 2.13 ± 0.17 g L⁻¹ 1,3-butadiene. The results indicate that we can produce unnatural/nonbiological compounds from glucose as a renewable carbon source via a rational enzyme design strategy.

Microorganisms cannot naturally produce 1,3-butadiene, an important monomer for synthetic rubber and plastic production, using glucose as carbon source. Here, the authors combine the cis,cis-muconic acid-production pathway and tailor ferulic acid decarboxylase mutations to achieve its production in E. coli.