Thermodynamics of globular protein native structure.

Area of Science:

• Biophysics
• Physical Chemistry
• Protein Science

Background:

• Understanding protein thermodynamics is crucial for molecular biology and drug design.
• Protein heat capacity is sensitive to structural changes and hydration.

Purpose of the Study:

• To analyze the temperature dependence of partial heat capacity in native protein structures.
• To investigate the contributions of vibrational and conformational components to heat capacity.
• To assess protein structural stability and the absence of early conformational transitions.

Main Methods:

• Analysis of partial heat capacity data as a function of temperature.
• Thermodynamic modeling of protein behavior in aqueous solution.
• Consideration of vibrational and conformational contributions to heat capacity.

Main Results:

• A strictly linear temperature dependence of partial heat capacity was observed.
• This linearity is attributed to vibrational and conformational components.
• The results indicate volume consistency and no conformational transitions before the main two-state transition.
• Protein structure organization relates to energy and conformational entropy.

Conclusions:

• The linear heat capacity dependence reflects a stable protein structure.
• Vibrational and conformational factors are key determinants of protein heat capacity.
• Proteins exhibit a two-level structural organization influencing their thermodynamic properties.