Thermodynamic effects of reduction of the active-site disulfide of Escherichia coli thioredoxin explored by differential scanning calorimetry

The structural variation of the thioredoxin protein in a disulfide active site of Escherichia coli due to oxdiation/reduction reaction is detected by differential scanning calorimetry. The active site contains a dithiol along with the disulfide. Isosteric double mutation process and thermal denaturation process are explained. The structural changes retard calculation of thermodynamic parameters.