chapter  3
22 Pages

Protein Engineering for Affinity Purification: The Str~tag

ByThomas G.M. Schmidt and Arm SUrra

Since the early days of protein chemistry the specific detection and the purification to homogeneity were the two critical problems that needed to be solved before the biochemical investigation of a protein could be commenced. Traditionally, a long series of precipitation, adsorption/ desorption, and column chromatography steps had to be carried out in order to obtain a pure protein. Although the advent of affinity chromatography made it possible to shorten the laborious procedure, a suitable combination of ligand, matrix, and elution conditions has first to be optimized in each case.