Figure 2: Recombinant altered PEDF proteins secreted to the culturing media were analyzed by anion-exchange column chromatography. Altered PEDF proteins were K146/K147/R149 (2 K,1R→3A) and K189/K191/R194/K197 (3 K,1R→4A), and FLAG-PEDF. (a) the backbone of the 3D structure of PEDF (tube in grey) from PDB 1IMV with highlighted location for amino acids K146/K147/R149 (blue) and K189/K191/R194/K197 (light blue). FLAG tagged PEDF had two tandem repeats of DYKDDDDK on the carboxy-end (C(A)). (b) Conductivity of PEDF fractions at peaks by anion-exchange column chromatography was determined and plotted.