From Negative Feedback to Integrated Control: Recombinase-Based Strategies for Mitigating Resource Competition.

Area of Science:

• Synthetic Biology
• Genetic Engineering
• Molecular Biology

Background:

• Resource competition between independently designed gene modules in host cells causes unintended interference.
• This interference disrupts circuit modularity and reduces the reliability of synthetic genetic systems.
• Developing strategies to mitigate interference is crucial for advancing synthetic biology.

Purpose of the Study:

• To discuss the development of recombinase-based control strategies to address interference in synthetic biology.
• To introduce the Re-NF controller for stabilizing module performance via negative feedback.
• To present the Re-NF-FF controller integrating negative feedback and feedforward regulation for improved resource allocation and predictability.

Main Methods:

• Utilizing recombinase-mediated promoter flipping for feedback and feedforward regulation.
• Designing a negative feedback (Re-NF) controller to adjust circuit activity based on resource usage.
• Developing an integrated negative feedback and feedforward (Re-NF-FF) controller using a single recombinase-mediated promoter flip.

Main Results:

• The Re-NF controller stabilizes module performance under fluctuating cellular conditions.
• The Re-NF-FF controller effectively balances resource allocation and reduces crosstalk between genetic modules.
• Both controllers demonstrate improved predictability in diverse circuit contexts.

Conclusions:

• Recombinase-based regulation offers a powerful approach to enhance robustness, predictability, and modularity in synthetic genetic systems.
• The Re-NF and Re-NF-FF controllers provide practical solutions for mitigating resource competition and interference.
• These strategies advance the engineering of reliable and predictable genetic circuits for synthetic biology applications.