Affinity Chromatography of Proteins

Abstract

Specific interactions between molecules are fundamental to all biological processes. In particular the interaction between proteins and specific binding components has been well established, e.g., between enzymes and their substrates, activators and inhibitors, between antibody and antigen, between some proteins and particular regions of DNA/RNA, or between receptors and their respective effector molecules such as hormones and transmitters. The technique of affinity chromatography relies on such biospecific affinity. The binding molecule which is fixed to the chromatographic matrix is called the ligand and the protein which is to be purified is called the counterligand or target protein. Specific and reversible binding to the immobilized ligand takes place via a biologically functional site on the surface of the target protein. Thus, affinity chromatography allows purification of most proteins to near homogeneity by utilizing the specific structure of the protein (for reviews see Scouten 1981; Wilchek et al. 1984).