Fig 1. Purification and SDS-PAGE of overexpressed Sup35 inE. coli under non-denatured Ni2+ affinity chromatography. (A) Elution curve of Sup35 under non-denatured Ni2+ affinity chromatography. Peak I and peak II appeared in approximately 5-50% and 50-100% imidazole gradients, respectively. The buffers used here were buffer A (20 mM Tris, pH 8.0, 1.2 M NaCl, 10 mM PMSF, 0% imidazole) and buffer B (20 mM Tris, pH 8.0, 1.2 M NaCl, 10 mM PMSF, 500 mM imidazole, 100%). (B) SDS-PAGE for the fractions in Figure 1A. All lanes were treated by SDS boiling. Slot represents for sample loading slots in stacking gel. Sup35, X1 and OmpF indicate the bands of Sup35 monomer, X1 protein and OmpF, respectively. Peak I + DTT and Peak II + DTT were boiled with 10 mM DTT. Lane M: molecular weight protein marker comprising 116 kDa, 66.2 kDa, 45 kDa, 35 kDa, 25 kDa, and 18.4 kDa.