Figure 2.

SDS–PAGE gels (15%, Coomassie Blue-stained) for the most relevant purification stages of the His₆-tagged recombinant Tm1743 enzyme. (a) Ni²⁺-chelating affinity purification of the recombinant enzyme. Lane M, molecular-mass standards (labelled in kDa); lane C, cell lysates; lane S, supernatant of the cell lysates; lane H, soluble fraction of the heated supernatant; lane B, Ni²⁺-chelating agarose beads bound with recombinant enzyme; lane E20, eluted samples from binding buffer containing 20 mM imidazole; lanes E50 and E100, samples eluted with 50 and 100 mM imidazole, respectively. (b) Size-exclusion chromatogram and SDS–PAGE analysis (inset) of the gel-filtration fractions (lane G) and the degraded recombinant enzyme (lane D).