Fig. 5.

Purification of GPX isoforms over BSP Sepharose. A) Chromatogram for recombinant GPX4, purified as shown in Fig. 1 and analyzed using mass spectrometry as in Fig. 4, over BSP Sepharose, showing three peaks of absorbance at 280 nm. B) GPX4 activity profile as measured in fractions of the chromatogram shown in A). C) Chromatography over BSP Sepharose with GPX4 activity measurements in selected fractions, using as start material either native GPX4 purified from human placenta (red) or recombinant GPX4 (blue). D) Chromatogram over BSP Sepharose for recombinant GPX1, purified as shown in Fig. 1, showing limited retention of the protein in the column. E) GPX1 activity measurements in fractions of the chromatography shown in D). (For interpretation of the references to colour in this figure legend, the reader is referred to the Web version of this article.)