FIG. 2.
Phosphoacceptor ability of wild-type protein IIAGlc and mutants H75Q and H75E. The phosphorylation reaction mixture contained 50 mM Tris-HCl (pH 8.0), 10 mM MgCl2, 1 mM dithiothreitol, 2 mM [32P]phosphoenolpyruvate, 3 μg of enzyme I, 6 μg of HPr, and 2 μg of IIAGlc as indicated. Lanes: 1, no IIAGlc; 2, wild-type IIAGlc; 3, H75Q IIAGlc; 4, H75E IIAGlc. Reaction mixtures were incubated at 37°C for 15 min, and proteins were separated on a sodium dodecyl sulfate–15% polyacrylamide gel. The 32P-labeled proteins were detected by autoradiography.