title: Determining thermodynamic parameters from isothermal calorimetric isotherms of the binding of macromolecules to metal cations originally chelated by a weak ligand.
abstract: An accurate data analysis method for determining stoichiometry and thermodynamic parameters from isothermal titration calorimetry data for the binding of macromolecules to metal cations that are solubilized through an association with a weak ligand is presented. This approach is applied to determine the binding constant for the association of Cu(II) to the first 16 residues of the Alzheimer's amyloid beta peptide, Abeta(1-16) under conditions where Cu(II) is rendered soluble through weak binding to glycine. At pH 7.2 and 37 degrees C, a binding constant of 1.5 x 10(9) M-1 (Kd = 0.7 nM) is determined for the association of Cu(II) with Abeta(1-16).
authors.affiliation: Department of Chemistry, Duke University, Durham, North Carolina 27708, USA.
authors.forename: Lian
authors.initials: L
authors.lastname: Hong
authors.forename: William D
authors.initials: WD
authors.lastname: Bush
authors.forename: Lanying Q
authors.initials: LQ
authors.lastname: Hatcher
authors.forename: John
authors.initials: J
authors.lastname: Simon