Cells can be engineered to produce useful chemicals, but the potential of such metabolic engineering has been limited by the arduous methods needed to measure the concentration of cellular metabolites.
Researchers have developed a strategy for fluorescence-based, real-time monitoring of the production of cellular products. The authors used genetically encoded biosensors based on inducible small-molecule systems to link the expression of fluorescent proteins to the intracellular amount of a product. The authors combined these biosensors with cells engineered to produce a particular metabolic product and used fluorescence intensity to track product formation in real time.
The authors also used the system to produce various plastic precursors and confirmed that higher fluorescence indicated higher product concentrations. In addition, the authors developed two biosensors for 3-hydroxypropionate (3HP), a renewable plastic precursor, and used real-time observation to improve 3HP production by 23-fold compared with previous reports.
Finally, the authors developed a method for in vivo production of acrylate, an important plastic precursor, from glucose, and monitored the production of two other commercially important chemicals, glucarate and muconate, showing that the technique had wide-ranging applications.
According to the authors, the technique could be used for high-throughput evaluation of metabolic engineering methods.