LAUSR

Dynamic regulation is a promising strategy for fine-tuning metabolic fluxes in microbial cell factories. However, few of these synthetic regulatory systems have been developed for central carbon metabolites. Here we created a set of programmable and bifunctional pyruvate-responsive genetic circuits for dynamic dual control (activation and inhibition) of central metabolism in Bacillus subtilis . We used these genetic circuits to design a feedback loop control system that relies on the intracellular concentration of pyruvate to fine-tune the target metabolic modules, leading to the glucaric acid titer increasing from 207 to 527 mg l −1 . The designed logic gate-based circuits were enabled by the characterization of a new antisense transcription mechanism in B. subtilis . In addition, a further increase to 802 mg l −1 was achieved by blocking the formation of by-products. Here, the constructed pyruvate-responsive genetic circuits are presented as effective tools for the dynamic control of central metabolism of microbial cell factories. Pyruvate-responsive circuits based on an orthologous transcription factor and adaptation of an antisense transcriptional circuit were developed to sense pyruvate in Bacillus subtilis and redirect metabolism for optimized glucaric acid production.