Energetics of myo-inositol hexasulfate binding to human acidic fibroblast growth factor effect of ionic strength and temperature.

The binding of myo-inositol hexasulfate to an N-terminal truncated 132-amino-acid human acidic fibroblast growth factor form was studied by isothermal titration calorimetry. The technique yields values for the enthalpy change and equilibrium constant, from which the Gibbs energy and entropy change can also be calculated. Experiments in different buffers and pH values show that the proton balance in the reaction is negligible.

Dissecting the energetics of the apoflavodoxin-FMN complex.

Many flavoproteins are non-covalent complexes between FMN and an apoprotein. To understand better the stability of flavoproteins, we have studied the energetics of the complex between FMN and the apoflavodoxin from Anabaena PCC 7119 by a combination of site-directed mutagenesis, titration calorimetry, equilibrium binding constant determinations, and x-ray crystallography. Comparison of the strength of the wild type and mutant apoflavodoxin-FMN complexes and that of the complexes between wild type apoflavodoxin and shortened FMN analogues (riboflavin and lumiflavin) allows the dissection of the binding energy into contributions associated with the different parts of the FMN molecule.

Measurement of biochemical affinities with a Gill titration calorimeter.

A Gill titration calorimeter is evaluated as an instrument to determine in one experiment the equilibrium constant and the enthalpy change of a biochemical reaction. The dimensionless parameter kc (the product of the association equilibrium constant and the concentration of the reagent to be titrated; Wiseman et al., Anal.

A calorimetric study of the thermal stability of barnase and its interaction with 3'GMP.

We have used high-sensitivity differential scanning calorimetry to characterize the thermal stability of barnase from Bacillus amyloliquefaciens in the pH range 2.0-5.0.