Understanding the structure, folding, and interaction of membrane proteins requires experimental tools to quantify the association of transmembrane (TM) helices. Here, we introduce isothermal titration calorimetry (ITC) to measure integrin αIIbβ3 TM complex affinity, to study the consequences of helix-helix preorientation in lipid bilayers, and to examine protein-induced lipid reorganization. P...

MICROCALORIMETRY Introduction Many industrial and biochemical applications depend on the usage of detergents and other surfactants. These compounds are indispensable, in particular, for the extraction, purification, and handling of membrane proteins. Owing to their amphiphilic nature, detergents can provide a membrane-mimetic environment required by integral membrane proteins to retain their na...

In the study of 1:1 binding by isothermal titration calorimetry, reagent concentration errors are fully absorbed in the data analysis, giving incorrect values for the key parameters--K, ΔH, and n--with no effect on the least-squares statistics. Reanalysis of results from an interlaboratory study of a selected biochemical process demonstrates that concentration errors are likely responsible for ...

Isothermal titration calorimetry (ITC) is one of the most interesting methods for the characterization of the interaction mechanisms of cyclodextrins (CDs) with drugs. In this review we explain how to conduct ITC experiments correctly for CD-guest interactions, how to choose an accurate fitting model for the titration curve and how to interpret carefully the ITC results. Finally, the use of ITC...

Relating thermodynamic parameters to structural and biochemical data allows a better understanding of substrate binding and its contribution to catalysis. The analysis of the binding of carbohydrates to proteins or enzymes is a special challenge because of the multiple interactions and forces involved. Isothermal titration calorimetry (ITC) provides a direct measure of binding enthalpy (DeltaHa...

Binding of ligands, ranging from proteins to ions, to membrane proteins is associated with absorption or release of heat that can be detected by isothermal titration calorimetry (ITC). Such measurements not only provide binding affinities but also afford direct access to thermodynamic parameters of binding--enthalpy, entropy and heat capacity. These parameters can be interpreted in a structural...