Measuring conformational stability of proteins using an optimized temperature-controlled capillary electrophoresis approach.
The thermal denaturation process of a model protein, bovine beta-lactoglobulin, was analyzed using capillary zone electrophoresis (CZE). For this purpose, a commercial CE apparatus was improved, allowing efficient control and accurate measurement of the temperature up to 95 degrees C. Under various pH conditions, transition temperature (Tm), enthalpy change (delta H) and entropy change (delta S) associated with the thermal denaturation were determined. Moreover, the technique is unique in its ability to estimate the heat capacity change (delta Cp). This work shows that CZE, performed even when electroosmotic flow occurs, is an innovative approach for determining the stability curves of proteins. Accordingly, CZE is a powerful tool to study protein unfolding/folding quickly and with minimal sample requirements.
D000818:Animals; D002417:Cattle; D004355:Drug Stability; D019075:Electrophoresis, Capillary / Q000379:methods*; D006358:Hot Temperature; D006863:Hydrogen-Ion Concentration; D007782:Lactoglobulins / Q000737:chemistry*; D011487:Protein Conformation; D011489:Protein Denaturation; D017510:Protein Folding; D013696:Temperature; D013816:Thermodynamics