Autophosphorylation of Wzc. Purified His-tagged Wzc was incubated with [γ-32P]ATP as a phosphate donor as described in Materials and Methods. The reaction was stopped at 0, 15, 30, 45, 60, 90, 120, and 240 min by adding sample buffer. An autoradiograph of these samples run on an SDS-polyacrylamide gel was developed.