Aminohexyl-sepharose affinity chromatography : purification of an auxin receptor

Affinity chromatography is a widely used technique that is based on specific binding, usually between proteins and low-molecular weight ligands. It is often found that the presence of a spacer arm between the supporting matrix and the affinity ligand is beneficial to binding capacity. A convenient starting material for affinity chromatography involving carboxyl-containing ligands is aminohexyl-Sepharose, which is commercially available and contains a spacer arm; any carboxyl-containing ligand can easily be coupled to the amino group of the resin. As an example of the use of aminohexyl-Sepharose, this chapter describes the purification of a soluble auxin receptor using an affinity resin produced by derivatization of aminohexyl-Sepharose.