Table 1.
Kinetic parameters of WT IPMK, extΔIPMK, and ΔIPMK.
| Kinase | kcat (s−1) | KM,ATP (μM) | kcat/KM,ATP (M−1s−1) | ATP kcat/KM Change Relative to WT | KM,PIP2 (μM) | kcat/KM,PIP2 (M−1s−1) | PIP2 kcat/KM Change Relative to WT |
|---|---|---|---|---|---|---|---|
| WT IPMK | 4.4 ± 0.2 | 61 ± 6 | 7.1 × 104 | 1.0 | 39 ± 5 | 1.2 × 105 | 1.0 |
| extΔIPMK | 7.5 ± 0.3 | 94 ± 11 | 8.0 × 104 | 1.1 | 37 ± 5 | 2.0 × 105 | 1.8 |
| ΔIPMK | 7.4 ± 0.8 | 300 ± 64 | 2.5 × 104 | 0.4 | 36 ± 4 | 2.0 × 105 | 1.8 |
Graphical representations and precise boundaries of each construct are provided in Fig. 1. Means ± SE using membrane capture assay, as described in Methods section.