Fig. 10. Purification and ATPase activity of the intragenic suppressor S27. (A) Aliquots (1 µg) of the glycerol gradient preparation of recombinant wild-type Prp22p, S635A and S27 were analyzed by SDS–PAGE. A Coomassie Blue-stained gel is shown. The asterisk marks the position of the Prp22 proteins. The positions and molecular weights (in kDa) of marker proteins are indicated on the left. (B) The ATPase activity of WT Prp22p, S635A and S27 is plotted as a function of input protein.