Differential scanning calorimetry experiments as a function of pH have been carried out for native hen egg white lysozyme and a three-disulphide derivative (CM6,127-lysozyme). The results indicate that the enthalpy (delta H298) and heat capacity changes (delta Cp) for unfolding are closely similar for the two proteins. This shows that the substantial reduction (25 degrees C at pH 3.8) in Tm resulting from removal of the 6-127 disulphide bond can, to a good approximation, be attributed totally to an increase in the entropy difference between the native and denatured states. The significance of this result for understanding the factors influencing the stability of folded proteins is discussed. Study holds ProTherm entries: 7122, 7123 Extra Details: disulphide bonds; differential scanning calorimetry; unfolding;,protein stability; thermodynamics
Submitter: Connie Wang
Submission Date: April 24, 2018, 8:33 p.m.
|Number of data points||4|
|Proteins||Lysozyme C ; Lysozyme C|
|Assays/Quantities/Protocols||Experimental Assay: dCp ; Experimental Assay: dHcal ; Experimental Assay: Tm ; Experimental Assay: dG|
|Libraries||Mutations for sequence KVFGRCELAAAMKRHGLDNYRGYSLGNWVCAAKFESNFNTQATNRNTDGSTDYGILQINSRWWCNDGRTPGSRNLCNIPCSALLSSDITASVNCAKKIVSDGNGMNAWVAWRNRCKGTDVQAWIRGCRL|