Fig 4. Ni-NTA purification of expressed proteins lead to high purity.

SDS-PAGE of the purified proteins, (A) VCL₂-Trypsin, (B) VCL₂-TEV, (C) VCL₂(G→R)-Trypsin, and (D) VCL₂(G→R)-TEV. Cell lysate was incubated with Ni-NTA resin and FT was collected. The column was washed with binding buffer, high salt buffer, and low imidazole buffer to remove non-specific bound proteins. His-tagged protein was eluted with buffer containing 100 mM (Elution-I), 250 mM (Elution-II), and 500 mM (Elution-III) imidazole with three fractions collected per concentration. Molecular weight standards in kDa, Ly = lysate, and FT = Flowthrough (containing the unbound protein).