FIGURE 4.

Purification of the recombinant Osu1 by RP-HPLC. Chromatographic separation of the Ni-NTA eluate by RP-HPLC using an analytical C₁₈ column and a gradient of aqueous acetonitrile containing 0.1% TFA, starting after 5 min from 20 to 60% CH₃CN during 40 min at a flow rate of 1 ml/min. Inside figure; (A) A 15% SDS-PAGE showing in lane 1 the molecular weight markers in kDa, and in lane 2, the pure recombinant Osu1 from the HPLC chromatogram obtained at the retention time of 23.5 min; and (B) A Western-blot showing in lane 1 the molecular weight markers in kDa, and in lane 2, the pure recombinant Osu1 from the HPLC chromatogram obtained at the retention time of 23.5 min developed using an anti-His antibody.