FIG. 2.

Degradation of Spx in vitro. Spx and ClpP were incubated at 37°C in the presence of ATP and an ATP-generating system with (+) or without (−) ClpC, ClpX, MecA, and YpbH as described in Materials and Methods. Samples were taken at the times indicated and were analyzed by SDS-polyacrylamide gel electrophoresis, followed by staining with Coomassie blue. Lane M, molecular mass markers. PK, pyruvate kinase, used as an ATP-regenerating system.