FIG. 5.
(A) Purified SfmA-C1-A1-PCP1 (lane 1), SfmB-C2-A2-PCP2 (lane 2), and SfmC-C3-A3-PCP3-RE (lane 3) as analyzed by electrophoresis on a 7.5% sodium dodecyl sulfate-polyacrylamide gel. The positions of molecular mass markers (lane 4) (in kilodaltons) are shown to the right of the gel. (B) Substrate specificities as determined by the ATP-PPi exchange reaction with the amino acids predicted to be incorporated into SFM-A (100% relative activity corresponds to 51,540 cpm for SfmA-C1-A1-PCP1, 44,300 cpm for SfmB-C2-A2-PCP2, and 51,500 cpm for SfmC-C3-A3-PCP3-RE).