TABLE 4.
Enzyme kinetic parameters assayed with p-S292 heptapeptide for wild-type and mutant SUMO-BDP carrying alanine substitutions in residues coordinated to the Mn2+ ions
The dephosphorylation reaction was carried out at 22 °C in 50 mm HEPES, pH 7.5, 7 mm MnCl2, and 100 mm KCl with increasing concentrations of Ser(P)-292 peptide. The kcat for wild-type SUMO-BDP is equivalent to a specific activity of 85 nmol/min/mg.
| SUMO-BDP | kcat | Km (Ser(P)-292) | kcat/Km (Ser(P)-292) |
|---|---|---|---|
| min−1 | μm | μm−1min−1 | |
| WT | 21.5 ± 1.2 | 3.1 ± 0.16 | 6.9 ± 0.64 |
| R104A | 21.9 ± 0.8 | 189 ± 15.6 | 0.116 ± 0.012 |
| H129A | 23.2 ± 1.4 | 5.2 ± 0.08 | 4.4 ± 0.48 |
| D109A | 0 | ||
| D127A | 0 | ||
| D298A | 0 | ||
| D337A | 0 |