The folding of the DNA duplex is accompanied by a decrease of heat capacity. In addition to the heat capacity contribution due to 'regular' dehydration, specific binding of water molecules to the minor groove of DNA forming the so-called spine of hydration could also be associated with a significant heat capacity contribution. In this diploma work, I have estimateted this contribution from the analysis of heat capacity changes and release of water molecules that accompany the binding of proteins to DNA. The heat capacity change has been divided into contributions related to dehydration of protein, regular dehydration of DNA and release of specifically bound waters. The thermodynamic analysis confirms that the heat capacity change due to the dehydration of the minor groove is similar to that of melting ice.
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