A new bacterial co-expression system for over-expressing soluble protein and validating protein-protein interaction

Area of Science:

• Molecular Biology
• Protein Expression
• Biochemistry

Background:

• Toxic, membrane, and hydrophobic proteins are challenging to express individually in Escherichia coli due to folding and stability requirements.
• Protein co-expression is a key strategy to obtain soluble proteins or protein complexes for these challenging targets.
• Existing co-expression systems are valuable for high-throughput validation of protein-protein interactions.

Purpose of the Study:

• To present a detailed experimental protocol for protein co-expression in Escherichia coli.
• To introduce the pHEX co-expression vector and its compatibility with commercial vectors like pGEX and pMAL.
• To enable efficient production and purification of difficult-to-express proteins.

Main Methods:

• Utilizing the pHEX co-expression vector in conjunction with commercial E. coli expression vectors (e.g., pGEX, pMAL).
• Co-expressing target proteins with binding partners to ensure proper folding and solubility.
• Employing tagged fusion protein expression for straightforward co-purification.

Main Results:

• Demonstration of a robust protocol for co-expressing challenging proteins.
• Successful co-expression and purification of toxic, membrane, and hydrophobic proteins.
• Validation of the pHEX vector's compatibility and utility in protein co-expression systems.

Conclusions:

• Protein co-expression is an effective strategy for producing difficult-to-express proteins in E. coli.
• The pHEX vector offers a versatile and compatible solution for protein co-expression and interaction studies.
• This protocol supports high-throughput validation of protein-protein interactions and facilitates the study of challenging protein classes.