Multi-gene Co-expression systems in E. coli: From single-vector designs to programmable expression platforms

Area of Science:

• Synthetic biology
• Microbial engineering
• Molecular biology

Background:

• Escherichia coli (E. coli) is a key host for recombinant protein production.
• Synthetic biology necessitates efficient co-expression of multiple genes in E. coli.
• Evolution from dual-gene to polygenic expression platforms is critical.

Purpose of the Study:

• To review major strategies for multigene co-expression in E. coli.
• To analyze mechanistic principles, trade-offs, and bottlenecks of these systems.
• To highlight applications and future directions in synthetic expression control.

Main Methods:

• Review of internal ribosome entry sites (IRES).
• Analysis of 2A self-cleaving peptides.
• Examination of dual-promoter cassettes, multicistronic operons, and multi-plasmid systems.

Main Results:

• Comparison of different co-expression strategies, noting challenges like translational imbalance and inclusion body formation.
• Demonstration of functional advantages through applications in metabolic engineering, protein assembly, and biomanufacturing.
• Identification of emerging programmable toolkits for advanced synthetic expression control.

Conclusions:

• Multigene co-expression systems in E. coli are crucial for advancing synthetic biology.
• Understanding design trade-offs and regulatory bottlenecks is essential for successful engineering.
• Future programmable toolkits promise next-generation control over microbial expression systems.