FIGURE 5.

Time course of accumulation of ADP-insensitive EP from E1Ca₂ and ATP. Microsomes expressing the wild type or mutant were phosphorylated with [γ-³²P]ATP at 0 °C for various periods in the presence of 0.1 m LiCl without KCl otherwise as in Fig. 4B. The total amount of EP and the amount of ADP-insensitive EP (E2P) were determined at the indicated time without and with the ADP addition in 0.1 m LiCl (no KCl), otherwise as in Fig. 4B. Solid lines show the least squares fit to a single exponential, and the apparent rates to reach the steady-state E2P level are given in Table 1.