Joint antisense RNA strategies for regulating isoprene production in Escherichia coli

Abstract

Isoprene (C₅H₈) is a key chemical ingredient for the production of synthetic rubber and plastic. Isoprene is commonly petro-chemically produced. Enabling sustainable microbial fermentation for isoprene production from potential biofuels is an attractive alternative to the original derivation. To this end, antisense RNA strategies, for redirection of weakening genes and control of metabolic pathways, were introduced to regulate the isoprene production. The isoprene titer, the intermediates of the methylerythritol 4-phosphate (MEP) pathway at the metabolic level and mRNA at the transcriptional level were all successfully affected as a consequence of simultaneous weakening of the farnesyl diphosphate synthase (ispA), octaprenyl diphosphate synthase (ispB) and undecaprenyl pyrophosphate synthase (ispU) of the MEP pathway in Escherichia coli BL21 (DE3). The finally obtained strain IAUB accumulated isoprene up to 16 mg L⁻¹ in a flask culture, which was about eight times of what was achieved by the control strain Idi. Detailed knowledge about the mechanisms of the novel strategies may benefit the development of many other bio-derived products.