Artificial Caprolactam-Specific Riboswitch as an Intracellular Metabolite Sensor

Area of Science:

• Synthetic biology
• Biotechnology
• Metabolic engineering

Background:

• Caprolactam is a key monomer for nylon-6 production.
• Biobased production of caprolactam using recombinant microbes is a growing field.
• Intracellular biosensors are crucial for high-throughput metabolic engineering.

Purpose of the Study:

• To develop a highly specific caprolactam biosensor.
• To enable precise metabolic engineering for improved caprolactam production.
• To overcome the challenge of mixed caprolactam and valerolactam production.

Main Methods:

• Development of an artificial riboswitch using a coupled in vitro-in vivo selection strategy.
• Utilizing a heterogeneous pool of RNA aptamers for riboswitch library construction.
• In vivo selection to identify a caprolactam-specific riboswitch.

Main Results:

• The artificial riboswitch demonstrated high specificity for caprolactam over valerolactam.
• A 3.36-fold activation of the riboswitch was observed in the presence of 50 mM caprolactam.
• The riboswitch enabled caprolactam-dependent control of microbial cell growth.

Conclusions:

• A novel, highly specific caprolactam riboswitch biosensor has been successfully developed.
• This biosensor is a valuable tool for metabolic engineering and improving biobased caprolactam production.
• The riboswitch facilitates precise control and optimization of nylon-6 precursor synthesis.