A Comprehensive Approach To Protein Thermal Stabilization

Engineering proteins for higher thermal stability is an important and difficult challenge. We describe a comprehensive and multidisciplinary approach incorporating various individual methods to redesign proteins to be more stable. First, we identified mutations for thermal stabilization of our model, adenylate kinase by applying a variety of experimental and computational techniques individually and separately. The used techniques include X-ray crystallography, molecular dynamics simulation, domain-swapping and structural bioinformatics. Then, we designed variants by combining the individual stabilizing mutations together. The resulting variants have mutations for extra electrostatic interactions by newly added ion pairs, additional hydrophobic interaction and/or optimized local structural entropy. In the experiment using differential scanning calorimetry, the redesigned proteins displayed considerable increases in their thermal stabilities. Our results highlight the importance of a comprehensive approach in protein thermal stabilization.