... melting curves of wild-type and mutants of SNase. DSC curves of five proteins [wild-type (WT), W140A,E140O, W140O and K133A]. The curves of W140A and W140Oare nearly linear in terms of intensity. ... 3961 of the wild-type protein and K133A and E142O were88.45, 84.70, and 83.60 kcalÆmol)1, respectively. Themelting point and DSC profile of E142O (52.8 °C) wasalmost identical with that of ... shows thefluorescence spectra of wild-type SNase and the fourmutants E142O, K133A, W140A and W140O. Thefluorescence spectra of E142O and K133A are similarto that of the wild-type protein. However,...