Microcalorimetry of proteins and their complexes

Ultrasensitive microcalorimetric techniques for measuring the heat capacities of proteins in dilute solutions over a broad temperature range (DSC) and the heats of protein reactions at fixed temperatures (ITC) are described and the methods of working with these instruments are considered. Particular attention is paid to analyzing the thermal properties of individual proteins, their stability, the energetics of their folding, and their association with specific macromolecular partners. Use of these calorimetric methods is illustrated with examples of small compact globular proteins, small proteins having loose noncompact structure, multidomain proteins, and protein complexes, particularly with DNA.