Mevalonate production by electro-fermentation in Escherichia coli via Mtr-based electron transfer system

Abstract

Although electro-fermentation is an emerging approach for enhancing microbial production, there has been limited demonstration of its utilization. In this study, the mevalonate pathway was introduced into synthetic electroactive Escherichia coli, which possesses an Mtr-based extracellular electron transfer pathway. To improve the mevalonate pathway in this strain, we aimed to regenerate an intracellular cofactor by supplying electrons from an electrode. Furthermore, the adhE gene, which is responsible for the accumulation of acetyl-CoA, the precursor of mevalonate production, was deleted and combined with electro-fermentation. As a result, mevalonate production was successfully improved by deleting the adhE gene and imposing a constant potential after 48 h of cultivation. Our results provide a new perspective for the improvement of bioproduction.