A portable expression resource for engineering cross-species genetic circuits and pathways

Area of Science:

• Synthetic Biology
• Metabolic Engineering
• Molecular Biology

Background:

• Genetic circuits and metabolic pathways are reengineered for chemical production.
• Current methods rely on host-specific parts, limiting scalability and unification.
• This fragmentation hinders progress in synthetic biology and metabolic engineering.

Purpose of the Study:

• To engineer a cross-species expression resource for unifying synthetic biology and metabolic engineering.
• To enable reuse of genetic parts across diverse organisms for similar functional outcomes.
• To achieve autonomous, self-regulated, and tuneable gene expression in bacteria.

Main Methods:

• Engineered a system combining mixed feedback control loops and cross-species translation signals.
• Developed an orthogonal polymerase system that functions without host-specific promoters.
• Characterized 50 system variants and employed mechanistic modeling to analyze system dynamics.

Main Results:

• Achieved nontoxic and tuneable gene expression in diverse Gram-positive and Gram-negative bacteria.
• Demonstrated that control loop architecture and feedback strengths regulate system dynamics, capacity, and toxicity.
• Successfully reused genetic parts to express a biosynthesis pathway in both model and non-model hosts.

Conclusions:

• The engineered cross-species expression resource unifies synthetic biology and metabolic engineering efforts.
• This resource enables consistent and scalable application of genetic circuits and pathways across bacterial species.
• The system offers a foundation for broader applications in biotechnology and synthetic biology.