Background
Selenoproteins, which incorporate the amino acid selenocysteine (Sec), are prized for their unique redox properties and catalytic capabilities in therapeutic antibodies, industrial enzymes, and diagnostic reagents. However, these proteins remain difficult and costly to produce in large quantities. Traditional chemical synthesis is labor-intensive and inefficient, while native biological sources provide only trace amounts.
Recombinant production in E. coli offers an attractive solution, but the incorporation of selenocysteine during translation presents significant technical barriers due to its complex biosynthetic requirements and sensitivity to selenium concentrations. Current bacterial expression systems rely on engineered tRNAs and auxiliary factors to introduce selenocysteine into proteins. These approaches are hampered by poor incorporation efficiency, toxicity from excess selenium, premature translation termination, and plasmid instability.
Furthermore, incompatibility with standard promoters and poor reproducibility across batches limit production scalability and industrial applicability. There remains a critical need for a robust, high-yield expression platform that supports stable and efficient production of Sec-containing proteins in microbial systems.
Technology overview
This technology introduces an engineered E. coli strain optimized for the recombinant production of selenocysteine-containing proteins, including complex antibodies and enzymes.
The strain was developed through targeted point mutations and adaptive evolution to tolerate selenium-rich environments and maintain its Sec incorporation machinery across generations. Importantly, the strain’s survival is linked to active selenocysteine incorporation, minimizing genetic drift and ensuring stable protein expression.
This platform addresses key limitations of prior systems by enabling higher yields of selenoproteins with enhanced incorporation fidelity and tolerance to selenium. Unlike standard hosts that lose function over time or exhibit toxic responses to selenium, this strain supports prolonged fermentation with consistent output. This platform sets a new standard for scalable, reproducible selenoprotein manufacturing.
Benefits
- Enables high-yield expression of selenocysteine-containing proteins
- Engineered for stable Sec machinery retention over multiple generations
- Tolerates high selenium concentrations without toxicity
- Produces functional antibodies and disulfide-rich enzymes
- Reduced batch variability and improved incorporation efficiency
Applications
- Therapeutic antibody production
- Industrial biocatalysis
- Diagnostic protein reagents
- Synthetic biology platforms
- Redox-active enzyme development
Opportunity
- Solves critical scalability and reproducibility issues in bacterial selenoprotein expression
- Ideal for commercial manufacturing of complex redox-active proteins
- Adaptable to future genetic enhancements for broader compatibility
- Available for exclusive licensing
Intellectual property
- Issued patents: US 11,155,804; JP 7269648
- Filed patents in HK, CN, CA, and EP
