Bioactive VEGF-C from E. coli.

Area of Science:

• Biotechnology
• Molecular Biology
• Protein Expression

Background:

• Vascular Endothelial Growth Factor-C (VEGF-C) promotes lymphatic vessel growth.
• Bacterial expression systems offer cost and time advantages but lack eukaryotic posttranslational modifications.
• Producing complex eukaryotic proteins like VEGF-C in bacteria presents challenges, particularly disulfide bond formation.

Purpose of the Study:

• To develop methods for producing biologically active VEGF-C using bacterial expression systems.
• To overcome limitations of bacterial expression for cysteine-rich proteins.
• To enable efficient and cost-effective production of VEGF-C.

Main Methods:

• Expressed truncated VEGF-C from cDNA and refolded inclusion bodies in vitro.
• Utilized a redox-modified E. coli cytoplasm (Origami strain) for direct expression.
• Fused VEGF-C to maltose-binding protein for expression in the engineered bacterial cytoplasm.

Main Results:

• Truncated VEGF-C expressed from inclusion bodies regained bioactivity after in vitro folding.
• Direct expression of VEGF-C mutants (lacking propeptides) in the Origami (DE3) strain's cytoplasm yielded bioactive protein.
• This study achieved the first direct expression of bioactive VEGF growth factor from E. coli, avoiding in vitro refolding.

Conclusions:

• Bioactive VEGF-C can be produced in E. coli using specific strategies.
• Engineering the bacterial cytoplasmic environment is crucial for correct disulfide bond formation in VEGF-C.
• Bacterial expression of VEGF-C is feasible, offering a more efficient alternative to traditional methods.