Determination of Binding Kinetics of Intrinsically Disordered Proteins by Surface Plasmon Resonance

Surface plasmon resonance (SPR) is an important and convenient method for measuring kinetic rate constants of given molecular interactions, equilibrium binding constants at steady state, or determinations of binding stoichiometry. In its traditional setup, SPR requires that one binding partner is tightly immobilized on the surface of a sensor chip either by direct chemical coupling to the surface-coated carboxymethylated dextran matrix or by non-covalent capture to a high-affinity binding partner that is covalently linked to the surface. The latter design of the sensor surface is highly advantageous compared to the direct chemical coupling as this setup ensures a homogeneous and specific orientation of the immobilized binding partner. This chapter provides guidelines for the design of capturing systems that generally provide high-end kinetic data suitable for determination of binding rate constants. This principle will be illustrated by the binding of synthetic peptides derived from an intrinsically disordered region of the endothelial glycosylphosphatidylinositol-anchored high-density lipoprotein binding protein 1 (GPIHBP1) to captured monoclonal antibodies.