FIG. 1.
Characterization of purified preparations of mutant PyrR proteins by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. A 10-μg sample of each protein was analyzed by electrophoresis on a 15% polyacrylamide gel, which was stained with Coomassie blue. The samples were wild-type PyrR (lane 1), T18A (lane 2), R19Q (lane 3), H22A (lane 4), R27Q (lane 5), T41I (lane 6), R141Q (lane 7), R145Q (lane 8), K152Q (lane 9), and molecular mass standard proteins (Life Technologies, Inc., Rockville, Md.) with apparent molecular masses in kilodaltons of each indicated by the arrows (lane 10).