AFFINITY PURIFICATION OF HISTIDINE-TAGGED PROTEINS

Expression of recombinant proteins is a standard technique in molecula r biology and a wide variety of prokaryotic as well as eukaryotic expr ession systems are currently in use. A limiting step is often the puri fication of the expressed recombinant protein, particularly if mammali an expression systems that yield low expression levels are employed. H ere, we discuss the advantages and restrictions of tagging recombinant proteins with histidines and purifying them by Ni2+-NTA chromatograph y.