Figure 4. Fusion-tag removal and purification of detagged GH1.
A. Lanes 1 and 2 show purified Bla-GH1 fusion protein before and after cleavage with SelecTEV protease. Lanes 3, 4 and 5 show flow-through, wash and elution fractions from IMAC purification following the cleavage reaction. Free GH1 was present in the flow-through. The 6×His-tagged Bla fragment and SelecTEV protease are retained on the column and released by elution with buffer containing 0.25 M imidazole. M, marker proteins.
B. Purified, detagged GH1 remained soluble upon centrifugation after 72 h at 4 °C.
