<i>In vitro</i> processing of the recombinant fusion protein ACP-G2-Amy-Histag contained in <i>E</i>. <i>coli</i> cell lysate was performed by mixing it with the clarified cell lysate of <i>E</i>. <i>coli</i> over-expressing protease TEV (supernatant-TEV), and subsequently target protein Amy was purified by one-step Ni-chelating chromatography.

<p>The supernatant of the cell lysate of <i>E</i>. <i>coli</i> expressing fusion protein ACP-G2-Amy-Histag was mixed with supernatant-TEV at a volumetric ration of 10:1 and incubated at 25°C. Aliquots were removed for SDS-PAGE analysis after 0 h, 2 h, 4 h, 6 h and 8 h. lane 1, the supernatant of the cell lysate of <i>E</i>. <i>coli</i> expressing fusion protein ACP-G2-Amy-Histag; lane 2, the supernatant of the cell lysate of <i>E</i>. <i>coli</i> expressing protease TEV by vector pET-28b-MBP-TEV-WHZ; lane 3, the supernatant of the cell lysate of <i>E</i>. <i>coli</i> expressing fusion protein ACP-G2-Amy-Histag treated by addition of the purified protease TEV; lane 4, target protein Amy purified by one-step Ni-chelating affinity chromatography.