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Structural transitions of carboxymethylated cytochrome c: calorimetric and circular dichroic studies
R Santucci1, A Giartosio, F Ascoli
1Department of Biochemical Sciences, University La Sapienza, Rome, Italy.
Abstract:
Circular dichroism and differential scanning calorimetry studies on the unfolding-refolding process of native and carboxymethylated cytochrome c, induced either by temperature or chemical agents, have been performed. The results have shown that the modified protein has a decreased conformational stability with respect to the native state, in agreement with a structure less compact, but still highly folded, which behaves as a thermodynamically stable "intermediate" between native and fully unfolded cytochrome c.
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