transcription-based biosensing of glycolate for prototyping of a complex enzyme cascade.

metabolic systems allow the reconstitution of natural and new-to-nature pathways outside of their cellular context and are of increasing interest in bottom-up synthetic biology, cell-free manufacturing, and metabolic engineering. Yet, the analysis of the activity of such networks is very often restricted by time- and cost-intensive methods. To overcome these limitations, we sought to develop an transcription (IVT)-based biosensing workflow that is compatible with the complex conditions of metabolism, such as the crotonyl-CoA/ethylmalonyl-CoA/hydroxybutyryl-CoA (CETCH) cycle, a 27-component metabolic system that converts CO into glycolate.