134813.fig.004a
(a)
134813.fig.004b
(b)
Figure 4: The divalent cation requirement for the phosphatase activity of hCaMKP-N(1–559). (a) hCaMKP-N(1–559) was assayed using pp10 as the substrate in the presence of the indicated divalent cations or EDTA instead of 2 mM MnCl2 as described in Section 2. The results are expressed as the percentage of the activity determined with 2 mM MnCl2. The data represent the average of three independent experiments ± S.D. (b) hCaMKP-N(1–559) was assayed using pp10 as the substrate in the presence of varying concentrations of MnCl2 (circles) or MgCl2 (triangles) instead of 2 mM MnCl2 .