Optimization of a recombinant BlaR-CTD protein formulation using the response surface methodology

Area of Science:

• Biochemistry
• Protein Engineering
• Molecular Biology

Background:

• The beta-lactam sensor-transducer protein (BlaR-CTD) from Bacillus licheniformis plays a crucial role in bacterial response systems.
• Recombinant protein expression is essential for studying protein function and developing biotechnological applications.
• Ensuring protein stability during formulation and storage is critical for practical use.

Purpose of the Study:

• To optimize the formulation of recombinant BlaR-CTD for enhanced thermal stability.
• To identify optimal excipients and buffer conditions for stabilizing the protein.
• To apply response surface methodology for efficient formulation development.

Main Methods:

• Recombinant BlaR-CTD was expressed in E. coli using the pColdI vector.
• Response Surface Methodology (RSM) with Central Composite Design (CCD) was employed to screen excipients and buffer conditions.
• Protein concentration was quantified using UV spectroscopy and the Bradford assay.
• Excipients screened included Glycerol, Sucrose, Triton x-100, and Tween-20, with Tris, Borate, and PBS buffers evaluated.

Main Results:

• Glycerol and sucrose were identified as key excipients for improving BlaR-CTD stability.
• The optimal formulation was determined to be pH 7.62, 15.35% glycerol, and 152.52 mM sucrose.
• These conditions significantly enhanced the thermal stability of the recombinant BlaR-CTD.

Conclusions:

• The study successfully identified optimal formulation parameters for recombinant BlaR-CTD.
• The developed formulation significantly improves the thermal stability of the protein, crucial for its potential applications.
• RSM is an effective tool for optimizing protein formulations in biotechnology.