Interactions between the polysaccharide chitosan and negatively charged phospholipid liposomes were studied as a function of compositional and environmental conditions. Using isothermal titration calorimetry, different levels of deprotonation of chitosan in acidic solutions were attained with titration of the fully protonated polymer at pH 4.48 into solutions with increasing pH. The process was...

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...

Isothermal titration calorimetry (ITC) is a straightforward method to determine basic chemical details of a binding interaction (affinity, thermodynamics and stoichiometry) in a single experiment and under native conditions [1, 2]. Traditionally, ITC experiments are performed using the method of incremental titration, whereby a precise volume of titrant is added to a solution of titrand at disc...

The unfolding enthalpy of the pH 4 molten globule from sperm whale apomyoglobin has been measured by isothermal titration calorimetry, using titration to acid pH. The unfolding enthalpy is close to zero at 20 degrees C, in contrast both to the positive values expected for peptide helices and the negative values reported for holomyoglobin and native apomyoglobin. At 20 degrees C, the hydrophobic...

A series of benzimidazo[1,2-c][1,2,3]thiadiazole-7-sulfonamides were synthesized and their binding to two carbonic anhydrase isozymes measured by isothermal titration calorimetry (ITC). Human carbonic anhydrase I (hCAI) and bovine carbonic anhydrase II (bCAII) bound the inhibitors with observed association constants in the range from 1.1 x 10(6) to 2.6 x 10(7) M(-1).

In this contribution we show that the newly discovered 6 + 6 biotin-formaldehyde macrocycle Biotin[6]uril binds a variety of anionic guest molecules in water. We discuss how and why the anions are bound based on data obtained using NMR spectroscopy, mass spectrometry, isothermal titration calorimetry (ITC), computational calculations and single crystal X-ray crystallography.

The host-guest interaction of a series of cyclohexyl-appended guests with cucurbit[8]uril (Q[8]) was studied by ¹H NMR spectroscopy, isothermal titration calorimetry (ITC), and X-ray crystallography. The X-ray structure revealed that two cycloalkane moieties can be simultaneously encapsulated in the hydrophobic cavity of the Q[8] host to form a ternary complex for the first time.

CRABP: cellular retinoic acid binding protein; CRBP: cellular retinol binding protein; FABP: fatty acid binding protein; I-BABP: intestinal bile acid binding protein; iLBP: intracellular lipid binding protein; ITC: isothermal titration calorimetry; PPAR: peroxisome proliferator activated receptor; PPRE: peroxisome proliferator responsive element; RAR: retinoic acid receptor; RARE: retinoic acid...

The purpose of this white paper is to compare four techniques utilized to quantify biomolecular interactions. It provides a brief introduction to each technique, followed by tables that provide a direct comparison. The four techniques compared in this white paper are Surface Plasmon Resonance (SPR), Isothermal Titration Calorimetry (ITC), Microscale Thermophoresis (MST), and Biolayer Interferom...