Figure 3.

IMAC purification of His-Prot-Pol*. (A) The insoluble fraction of a lysate from induced cultures of E. coli transformed with the plasmid pet11a-His-Prot-Pol* was solubilized in 8 M urea buffer and subjected to IMAC. The individual imidazole elution fractions were resolved via SDS-PAGE and stained using Coomassie. Note the two different protein species with an apparent molecular mass of 60 kDa (His-Prot-Pol*) and 35 kDa (His-Prot) that were specifically eluted with increasing imidazole concentrations. (B) Refolded IMAC purified His-Prot-Pol* and His-Prot after the addition of PBS and re-concentration using an ultrafiltration device. His-Prot-Pol* and His-Prot are marked with an arrow.