Unmet Need
The ability to incorporate a wide variety of non-canonical amino acids (ncAAs) into proteins holds great potential for expanding the diversity and functionality of the proteome. While significant progress has been made in expanding the genetic code through recoding stop and sense codons, the efficient translation of quadruplet codons, which consist of four bases instead of the typical three, remains a significant challenge. Quadruplet codons have the potential to create 255 possible codons, vastly increasing the possibilities for incorporating ncAAs into proteins. However, limitations in translational efficiency and competition with host cellular machinery have hindered the widespread application of this expanded codon system.
Value Proposition
This technology overcomes these challenges by employing engineered E. coli tRNAs capable of translating quadruplet codons, dramatically improving the efficiency of genetic code expansion (GCE) technologies. By utilizing phage-assisted continuous evolution (qtRNA-PACE), the system evolves tRNAs with up to 80-fold improvements in translation efficiency, optimizing their ability to decode quadruplet codons. Furthermore, the development of multicistronic tRNA operons allows the simultaneous decoding of multiple quadruplet codons within a single system, advancing the potential to incorporate a broad spectrum of ncAAs into proteins. This breakthrough paves the way for the practical use of quadruplet codon systems in living organisms, offering a robust platform for the development of novel proteins with expanded functionality.
Key Differentiators
- Quadruplet Codon Decoding – Engineering tRNAs that decode quadruplet codons, expanding the genetic code and enabling the incorporation of non-canonical amino acids.
- Phage-Assisted Continuous Evolution (qtRNA-PACE) – A powerful strategy to evolve tRNAs for enhanced decoding efficiency without requiring genome modifications.
- High Efficiency – Evolved qtRNAs improve quadruplet codon translation efficiencies by up to 80-fold, reaching suppression efficiencies comparable to traditional amber suppression.
- Multiplexing Capability – Successful translation of multiple consecutive quadruplet codons in a single reporter protein, enabling complex protein synthesis.
- Strain-Independent Improvements – qtRNA evolution leads to strain-independent improvements in suppression activity, allowing for robust expression in wild-type and knockout strains.
Applications
- Protein Engineering – Use of quadruplet codons to incorporate a broader range of non-canonical amino acids, expanding the functional diversity of proteins for research and therapeutic applications.
- Synthetic Biology – Creation of novel, functionally diverse proteins by expanding the genetic code with multiple non-canonical amino acids.
- Drug Discovery – Development of proteins with enhanced or novel properties through the incorporation of non-canonical amino acids, useful in drug screening and biomolecular design.
- Biotechnology – Engineering microbes or cells to produce proteins with expanded functional groups for industrial or therapeutic purposes.
- Development of an Exclusively Quadruplet Codon Translation System – The framework may serve as the basis for future systems utilizing quadruplet codons in a fully expanded genetic code.
Keywords
Quadruplet codons, tRNA engineering, genetic code expansion, phage-assisted continuous evolution, non-canonical amino acids, protein engineering, synthetic biology, genetic code, E. coli, ribosome engineering.
