High-throughput solubility assay for purified recombinant protein immunogens

Area of Science:

• Biochemistry
• Proteomics
• Assay Development

Background:

• Recombinant protein production is crucial for research and therapeutics.
• Accurate assessment of protein solubility is essential for successful protein expression and application.
• Existing methods for solubility analysis can be low-throughput and labor-intensive.

Purpose of the Study:

• To develop and validate a high-throughput assay for determining recombinant protein solubility.
• To compare experimental solubility data with theoretical hydrophobicity predictions.
• To emphasize the importance of experimental solubility determination.

Main Methods:

• A novel high-throughput assay utilizing affinity purification in the presence of chaotropic agents.
• Subsequent dilution and incubation steps to assess protein solubility under non-chaotropic conditions.
• Application of the assay in a 96-well format for large-scale screening.

Main Results:

• The assay successfully measured the solubility of 125 different recombinant proteins.
• A weak correlation was observed between experimentally determined solubility and calculated hydrophobicity values.
• This suggests that theoretical predictions alone are insufficient for assessing protein solubility.

Conclusions:

• The developed high-throughput assay is effective for analyzing recombinant protein solubility.
• Experimental validation is critical, as theoretical hydrophobicity does not reliably predict solubility.
• This assay facilitates large-scale solubility screening in proteomics and drug discovery efforts.